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*I'd like to add a note about how and why various psychological conditions become "disorders" or "diseases" (or have such classifications taken away, as in the case of homosexuality) in the field of medicine. The main reasons are usually ] rather than political. The way modern medicine works is that every medical condition, procedure, problem, disorder, etc., must have a ]. Without said code, insurance companies (and/or the ]) will not pay the doctor's or hospital's bills. Thus, every time a new edition of the ] is published, it is much larger than the last (as are the manuals for all other fields of medicine), because it's the only way psychiatrists, psychologists, therapists, and other health professionals can get paid for the latest and greatest treatments. As a result, there is tremendous pressure on the commitees responsible for such manuals to accept almost every newly coined term in medicine, regardless of how many people actually may qualify as having any such new given condition, or even whether it's been generally accepted throughout the entire medical commitee. In short, it's a very, very political process, and always has been. Usually the politics are driven by business interests, but sometimes they're politics of a far more ideological nature, which is what happened in the case of homosexuality being dropped from the DSM-IV. Does the fact that homosexuality was removed from the DSM-IV truly mean that homosexuality is unquestionably ''not'' a mental disorder (in the purely clinical sense of "not being the norm")? Or that it unquestionably ''is''? Not at all. Even now, in the early ], we know very little about the way the brain works, and even less as to what truly causes a given person to grow up to self-identify as belonging to a particular sexual orientation. It s entirely possible that, at some point in the future, someone will come up with some sort of ] that will cause all humans to whom it is given to lose all homosexual urges. Likewise, someone could come up with a therapy to make all humans ''gain'' homosexual urges. Maybe it will never happen. We just don't know. And these possibilities will remain no matter what the psychological establishment deems to be The One Truth on this, or any other, psychological issue. --] 04:16, 15 January 2006 (UTC) *I'd like to add a note about how and why various psychological conditions become "disorders" or "diseases" (or have such classifications taken away, as in the case of homosexuality) in the field of medicine. The main reasons are usually ] rather than political. The way modern medicine works is that every medical condition, procedure, problem, disorder, etc., must have a ]. Without said code, insurance companies (and/or the ]) will not pay the doctor's or hospital's bills. Thus, every time a new edition of the ] is published, it is much larger than the last (as are the manuals for all other fields of medicine), because it's the only way psychiatrists, psychologists, therapists, and other health professionals can get paid for the latest and greatest treatments. As a result, there is tremendous pressure on the commitees responsible for such manuals to accept almost every newly coined term in medicine, regardless of how many people actually may qualify as having any such new given condition, or even whether it's been generally accepted throughout the entire medical commitee. In short, it's a very, very political process, and always has been. Usually the politics are driven by business interests, but sometimes they're politics of a far more ideological nature, which is what happened in the case of homosexuality being dropped from the DSM-IV. Does the fact that homosexuality was removed from the DSM-IV truly mean that homosexuality is unquestionably ''not'' a mental disorder (in the purely clinical sense of "not being the norm")? Or that it unquestionably ''is''? Not at all. Even now, in the early ], we know very little about the way the brain works, and even less as to what truly causes a given person to grow up to self-identify as belonging to a particular sexual orientation. It s entirely possible that, at some point in the future, someone will come up with some sort of ] that will cause all humans to whom it is given to lose all homosexual urges. Likewise, someone could come up with a therapy to make all humans ''gain'' homosexual urges. Maybe it will never happen. We just don't know. And these possibilities will remain no matter what the psychological establishment deems to be The One Truth on this, or any other, psychological issue. --] 04:16, 15 January 2006 (UTC)
*Another very informative answer! What is a "disorder" is somewhat in the eyes of the beholder. Overeating, smoking, and flying on the ] are all unhealthy in the sense that they reduce one's life expectancy, statistially speaking. There are certainly clinical efforts to help people quit smoking and overeating - not sure about the shuttle. :-) Should they all be considered disorders? ]\<sup>]</sup> 04:49, 15 January 2006 (UTC) *Another very informative answer! What is a "disorder" is somewhat in the eyes of the beholder. Overeating, smoking, and flying on the ] are all unhealthy in the sense that they reduce one's life expectancy, statistially speaking. There are certainly clinical efforts to help people quit smoking and overeating - not sure about the shuttle. :-) Should they all be considered disorders? ]\<sup>]</sup> 04:49, 15 January 2006 (UTC)
As a person who does not discriminate by gender, I take great exception to Alteripse's implication that "homosexuality is not a disease" is a political stance. There is far more evidence that homosexuality is a natural phenomenon than a disease/disorder. To "wait for findings", as it were, would be like questioning the holocaust because you've never visited Germany. It has far reaching social, not political, consequences. I know what you are proposing doesn't necessarily imply homophobia, but it fosters it terribly. As a person who does not discriminate by gender, I take great exception to Alteripse's implication that "homosexuality is not a disease" is a political stance. There is far more evidence that homosexuality is a natural phenomenon than a disease/disorder. To "wait for findings", as it were, would be like questioning the holocaust because you've never visited Germany. It has far reaching social, not political, consequences. I know what you are proposing doesn't necessarily imply homophobia, but it fosters it terribly.<small>&mdash;''the preceding ] comment is by'' ] (]&nbsp;&bull;&nbsp;]) 22:44, 14 January 2006 (UTC{{{3|}}})</small><!--Inserted with Template:Unsigned2-->
*Some people are born with ]. Does that make it a "natural phenomenom" or a "disease". These are really just labels. ]\<sup>]</sup> 05:52, 15 January 2006 (UTC)


== computer science projects == == computer science projects ==

Revision as of 05:52, 15 January 2006

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January 8

Circulatory System

== How long does it take for a drop of blood to travel through your entire body? ==

Could a link please by supplied to a reliable source... thanks --Ike 01:18, 8 January 2006 (UTC)

Well, you're going to have a hard time finding a straight answer, because blood doesn't travel in drops, and some paths back to the heart are short while others are very long (going through mazes of capillaries). —Keenan Pepper 02:41, 8 January 2006 (UTC)
Keenan's right. Any given drop of blood will travel along random pathways throughout the circulatory system, and during that journey the fluid and cellular components of blood are continually exchanged. So the answer to your question is : "it depends".
Of more use to you may be that there is a way of averaging this, which doctors use, based on a person's cardiac output. The link, & its links, give some reasonably detailed information, but in short:
  • Average heart rate =70 beats/minute, average stroke volume (amount pumped in a single beat from the left ventricle) = 70mL.
  • Cardiac output = Heart rate x stroke volume, so cardiac output = ~4.9L/min. (A gallon is about 4.5L if you're in the US & don't do metric). -- Clearly I don't do antiquated and unnecessarily complex measurement systems. A gallon is 3.785L according to this. --Mattopaedia 08:37, 8 January 2006 (UTC)
  • Average blood volume is about 8% bodyweight in kg. So for the "average" 70kg man, blood volume is about 5.6L.
  • So, the heart pumps the equivalent of total blood volume about every 68 seconds.
Any human physiology text can give you these details. To check my numbers, I used Guyton & Hall (1996), Textbook of Physiology (9th Ed). Hope that helps. Mattopaedia 05:47, 8 January 2006 (UTC)

how does an oil derrick function

Have you looked at Oil derrick? Black Carrot 06:38, 8 January 2006 (UTC)

When was the first offshore oil drilling rig in the US built?

It seems in 1894, "Summerland, the first offshore oil field to be developed in the United States, had been discovered near Santa Barbara, California." In 1903, a "wooden pier that rested on stilt-like piles stretched out into the ocean at Summerland and a number of rigs drilled from it." - Akamad 03:49, 8 January 2006 (UTC)

Black Holes

I am a tad confused about the concept of, what is described in our article on black holes as "narrow jets of particles at relativistic speeds." I was wondering how this works, because I was under the impression that the gravity in a black hole was strong enough such that no matter can escape its gravitational pull. So how is it possible that the black hole can "eject" particles outwards and away from it's über strong gravity? Thank you. - Akamad 03:42, 8 January 2006 (UTC)

The particles are not coming from inside the black hole, but from the accretion disk of matter around it. The particles can still escape from the black hole's gravity as long as they have not passed the event horizon. —Keenan Pepper 06:03, 8 January 2006 (UTC)
In fact, this allow virtual particles that form at the edge of the event horizon but not past it, to separate from each other before they annihilate, then being ejected, resulting in hawking radiation. Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 09:50, 8 January 2006 (UTC)
Thanks for the responses. - Akamad 19:20, 8 January 2006 (UTC)

Jews

Are Jews (the people group, not the religion) smarter as a race? Because there seems to be alot of famous Jewish people, for exanple 22% percebt of Nobel Prize winners are Jews. So, do the Jews have a genetic or ethnic advantage in mental intellengence?

I don't think so, but i do think that Jewish people are extreeeemely cool :D --Cosmic girl 04:00, 8 January 2006 (UTC)
Misplaced Pages has an article on Race and intelligence. - Akamad 04:34, 8 January 2006 (UTC)
The typical explanation is that Jewish culture values education and study more than other cultures. StuRat 07:25, 8 January 2006 (UTC)
Several years ago I read that Jews have the highest rate of geniuses per capita than any other race/nationallity/etc (not sure which). Scots came 2nd. Unfortunately I don't know any details of the research. AllanHainey 14:02, 9 January 2006 (UTC)
Bear in mind that this would be observed geniuses per capita, not actual genuises per capita. There may be many potential genuises in other societies which never had the opportunity to develop their intellect, due to cultural differences. StuRat 02:39, 10 January 2006 (UTC)
There are really next to no differences between ethnic groups genetically. Certainly not enough to make one race significantly more intelligent than another. StuRat's response seems reasonable, but any answer that takes genetics into account is simply racism, in the most basic sense of the term. --128.122.89.185 12:54, 14 January 2006 (UTC)

Speed of light

If nothing can reach the speed of light, why can light or electrons reach it?

Nothing can exceed the speed of light, and from what I gather, electrons cannot reach the speed of light anyway. - Akamad 04:25, 8 January 2006 (UTC)
And light, by definition, travels at the speed of light in a vacuum. - Akamad 04:30, 8 January 2006 (UTC)
If the light is not in a vacuum, it gets slowed down and other things (such as electrons) can travel faster than it. --AySz88^-^ 04:37, 8 January 2006 (UTC)
(edit conflict) It is not exactly true that nothing can reach the speed of light. To be more precise, although still not very precise, it is, according to current physics, impossible to accelerate matter up to or beyond the speed of light; that is, the speed of electromagnetic radiation in a vacuum. It is theoretically possible to have particles that have an imaginary rest mass and so always travel faster than light (tachyons), and I believe that photons (the particle associated with light), being massless, must travel at the "speed of light". Also note that the relevant limit is c, the speed of light in a vacuum. Electrons can be accelerated to very close to c. If they are traveling in something like glass or water, they can actually travel faster than light can travel in that medium, without ever exceeding c. This produces Cerenkov radiation, approximately similar to a sonic boom. This explanation is oversimplified and others more knowledgeable than I should feel free to correct me. — Knowledge Seeker 04:45, 8 January 2006 (UTC)
It's a common misconception that electrons go the speed of light in a wire. The electric current as a whole does go the speed of light, but the individual electrons don't go anywhere near that speed. The average speed of the electrons (the drift velocity) is about a millimeter per second, depending on the thickness of the wire and other factors. A good analogy is a water faucet. When you turn the faucet on, water instantly comes out, but that doesn't mean it came all the way from the water tower in that amount of time. The water was waiting in the pipe. When you turn on a light switch, the electrons going through the light bulb were already there waiting in the wires. They just get "pushed out" by the electrons coming from the power plant, so to speak. —Keenan Pepper 06:14, 8 January 2006 (UTC)
And to further clarify to other readers, the speed of light of an electric current comes in if say, that power plant was two light seconds away (and ignoring what would be massive amount of electric resistance in the wire, let's just assume it's a mile thick :p), then it would take two seconds for the electrons in the filament of the light bulb to start moving the moment the switch is flicked. The electrons from the power station electrons 600,000 km away (roughly) will take two seconds to push all the electrons between them and the electrons in the filament in order to get the electrons in the filament going. This is a necessary consequence, because otherwise you could transmit physical information (which represents order, something covered by the laws of thermodynamics faster than c. Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 09:58, 8 January 2006 (UTC)
Hmmm, I'm not sure that's exactly true. If someone flipped a switch at the power plant, then it would definitely take two seconds for the light to turn on, but if you flipped a switch at your house, I don't think it would matter how far away the power plant was. Not really sure though, I bet it's some complicated differential equation or something... —Keenan Pepper 23:18, 8 January 2006 (UTC)
Hmmm, actually yes, electromotive force is still present in the circuit near the house (because of the supply to other places of demand). I was assuming a 1:1 correlation with the power plant and my house. That would pose an interesting question though. A broken circuit is likely to generate no EMF in the current and when closed, it would have to take 2 seconds to emerge and travel to my house, I would think? Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 06:18, 9 January 2006 (UTC)
In the case of turning a light with other circuits on nearby, the light will partially come on immediately (ignoring the short distance to the next circuit), that is it will be sharing current with the other circuits (other circuits will dim), but for the complete return to the steady state, it will take the full 2 seconds. Or twice that. The generator can't compensate by generating more current until it "senses" the variation of resistance on the line, and the varied current goes the other way. 2 seconds each way. (Actually, though, the speed of EMF changes in a wire is not c but approximately c/2 or so, depending on the material. The potential difference propagates atom to atom, which turns out to be less than c (but of the same order of magnitude)) GangofOne 18:59, 9 January 2006 (UTC)
Nothing with mass can reach the speed of light; photons are massless therefore they can, but cannot exceed it. --128.122.89.185 12:56, 14 January 2006 (UTC)

is breaking the sound barrier as easy as snapping your fingers?

is breaking the sound barrier as easy as snapping your fingers? if you snap your fingers, is the resulting sound due to breaking the sound barrier, the subsequent impact, or simply the loss of force due to friction?

The sound comes from your fingertip hitting the base of your thumb. No sonic booms involved. —Ilmari Karonen (talk) 05:58, 8 January 2006 (UTC)
I agree there's no sonic boom, however I think your statement isn't completely true. When you click your fingers, what causes the sound is that you lean your ring finger to the base of your thumb and you snap your middle finger to it. If you do not put your ring finger there, and snap your middle finger that way, you don't get a click, only a much weaker thump sound, because the pad at base of the thumb is much softer than your ring finger which has a bone close to the surface. (It it, however, possible to use different fingers instead of the middle and ring finger and still produce the clicking sound, but this combination is the best. You can even use a finger of your other hand instead of your ring finger.) I am not sure, but I think that the vedge-shaped gap formed between the ring finger and base of the thumb might also take part in producing the sound.
For a sonic boom, you need an object moving with at least 300 m/s, and I don't suppose your finger would move with more than 0.5 m/s in a simple finger clicking. – b_jonas 14:09, 8 January 2006 (UTC)
When I snap, my ring finger and pinky together with the palm of my hand form a hollow cavity that acts as a resonator. If I move my pinky away, the resonator is smaller, so it sounds higher. —Keenan Pepper 22:44, 8 January 2006 (UTC)
Snapping a whip is the easiest way to create a sonic boom. StuRat 07:09, 8 January 2006 (UTC)


if you google "sound geocities barrier snap" the very first page offered claims that a boom does occur on a very small scale.

Light in orbit

Given that light can be pulled inwards by gravity(by something as massive as a black hole), and that it has a reliable velocity, and that those are the only two characteristics necessary for something to move into orbit around a celestial body, it there light endlessly orbiting black holes? Is there a distance out from a black hole at which, if you weren't pulled apart by the gravity or something like that, you would see a ring of light all around you? Because that would be pretty cool. It'd be fun to imagine something so absolutely black(except radiation) being encased by a sphere of pure light. If so, would that be near the event horizon? One problem I've found with this is that black holes are constantly expanding, so the orbital distance would be increasing as well, meaning any light currently in perfect orbit would eventually get pulled in, but maybe that's not a problem. --Black Carrot 06:52, 8 January 2006 (UTC)

I believe the orbital distance would be the event horizon. You are right that those orbits would be unstable due to the increasing size of the black hole. Therefore, I would expect you would find some, but not much, light in orbit at any given time. StuRat 07:13, 8 January 2006 (UTC)
Yes, as I understand it, the event horizon would be defined by the distance at which light almost escapes but not quite, and would therefore presumably contain some light "orbiting" the black hole. However, it would not appear as a sphere of light as you describe. If you are at a distance from the black hole, the light is on the event horizon and therefore unable to reach your eyes. Remember, for you to see a photon, it must reach your eyes. It doesn't shine in all directions. If it's orbiting, it will be invisible unless it breaks free somehow and travels toward you instead. Note that you may be able to see black-hole–related phenomena, including light trapped near the event horizon, but orbiting light shouldn't be one of them, as far as I can tell. — Knowledge Seeker 07:36, 8 January 2006 (UTC)
If a black hole had a constant mass and a photon would be in orbit at that distance (I'll assume that that's the event horizon) then it would stay there, I presume. But how would it get there? As soon as it's within the event horizon it's lost. So it has to approach from the outside. The only way for it to do that would be to spiral in. But because it has to stabilise at exactly that distance that would only happen after an infinite amount of time. So I imagine there might be a halo of spiralling (not orbiting) photons just outside the event horizon, but none exactly at the event horizon. But even if the black hole were to expand a bit, then I don't think any photons would fall into place in that orbit, but that's just gut feeling. DirkvdM 10:09, 8 January 2006 (UTC)
The photons could also come in along a tangent to the event horizon, or what works out as a tangent, taking into account the bending of the ray, as it approaches the black hole. Also note that objects falling into the black hole would tend to dislodge photons from orbit as they pass the event horizon. StuRat 11:08, 8 January 2006 (UTC)
I am not an expert from this, but I'll try to give some answers. You can find some interesting discussion on these effects on .
From what I understand, there is indeed such a sphere where light could circle endlessly, and this can happen not only for black holes but other very dense stars that are not dense enough to form a blackhole but aren't far from it. However, this light orbit is not stable: light circling on that sphere will eventually either fall in or escape outwards, so there will be no glowing "sphere of pure light". However, this sphere can cause odd visual effects, namely you can see distorted images of the sky around that are from photons that have circled near this sphere a few times.
Also I think this sphere is not the event horizon, but it is outside of it, but I am not sure of this (I think I don't even understand what the event horizon is exactly). – b_jonas 13:16, 8 January 2006 (UTC)
You're correct. At the distance where light moving in a circle around the hole stays in orbit, light moving away from the black hole can still escape. If you could stand there, the black hole would appear to cover exactly half of the sky. At the event horizon, on the other hand, no light can escape. A hypothetical observer standing motionless at the event horizon would see the black hole cover the entire sky, with the possible exception of a single point of light straight above. —Ilmari Karonen (talk) 16:06, 8 January 2006 (UTC)
(Well, that is, if a) it was possible to stay motionless at the event horizon, and b) we could ignore all this weird stuff about space and time being relative. But you get the idea.) —Ilmari Karonen (talk) 16:11, 8 January 2006 (UTC)
What I don't understand is that the page I linked above claims that this sphere has a radius that's a constant multiply of the radius of the event horizon. But it also claims that dense neutron stars that aren't black holes could also have such a sphere. Don't these two claims contradict? – b_jonas 21:18, 8 January 2006 (UTC)
The radius at which light orbits is not the same as the Schwarzschild radius (the radius of the event horizon), but a constant multiple of it. Every mass has a Schwarzschild radius. If a mass is compressed inside its Schwarzschild radius, it becomes a black hole, but it is possible for it to be compressed inside the light-orbiting radius but still outside the Schwarzschild radius, so it has a photon sphere even though it's not a black hole. —Keenan Pepper 22:56, 8 January 2006 (UTC)
To be specific, it's exactly 3/2 the Schwarzschild radius. —Keenan Pepper 22:58, 8 January 2006 (UTC)
Thanks for the clarification. – b_jonas 20:48, 12 January 2006 (UTC)

Security vulnerability

In a typical software company (like Microsoft, Apple, Sun Microsystems, etc.), did the programmer(s) responsible for a security vulnerability (wrote the code that caused the vulnerability, that is) got punished or disciplined in some way? --61.94.149.59 07:28, 8 January 2006 (UTC)

There is an assumption in your question that all vulnerabilities are due to either malicious or unintentional errors by programmers. On the contrary, I think many vulnerabilities are inherent in the high-level design of a program. If programmers are asked to make an operating system that will execute programs on your computer which are downloaded off the internet, without your permission, this is an inherent vulnerability. Think of it as if you left your house key under the door mat in case somebody needed access to your house, like a firefighter. Obviously, anyone can find the key and gain access. StuRat 08:23, 8 January 2006 (UTC)
This is an excellent point -- many vulnerabilities are indeed "inherent", although this obviously does not necessarily mean that they were inevitable. And in the case of an operating system that performs the stupefyingly risky operation of "executing programs on your computer which are downloaded off the internet, without your permission", I think we could use a slightly different analogy. Here's one: instead of mailboxes, some houses have mail slots in the front door. Suppose that the builder of your house (and all the houses on your street) decided to make the "mail slot" two feet wide and three feet high, so that the mailman could deliver large parcels as well as just letters. And suppose that nobody realized (until 95% of the front doors in the world had these gigantic "mail slots") that it was possible for a person to crawl through them... Steve Summit (talk) 19:39, 10 January 2006 (UTC)
You can add a supplemental security system that denies access to people it regonizes as bad, but that still lets lots of bad people in which aren't recognized. Similarly, a virus-check program can only stop those viruses it recognizes. A more practical approach to security would be to ban all access to your computer to everyone you haven't specifically authorized to have access. StuRat 08:23, 8 January 2006 (UTC)
Uh, I think I should be more specific. Actually, what I mean is security vulnerability caused by programming mistakes (e.g., incorrect authentication routines, unchecked buffer, etc.), not security risks in general. To be more specific, do someone in the company get punished for making mistakes in program code that turned into a security vulnerability? 61.94.149.59 08:55, 8 January 2006 (UTC)
As a general rule, there are computer companies that flood us with vulnerabilities that should never have been there in the first place, and there are computer companies you never hear in the news about vulnerabilities because we go 10 years or more between them having a flaw (IBM for example). This is because the latter have systems to catch vulnerabilities in development before the product goes to the customers, This requires extensive testing of the software, which adds to the cost of the product. Because the market demands cheapest possible products, the market gets what it pays for, products that have not been properly tested to make sure they have no security vulnerabilities. If the programmers that did the poor programming are no longer working at the place where they did the bad code, it is unlikely that the company will go after them, if it even knows who done it. The industry, that has won the market share war, has a dismal record of security standards, compared to in computer historical standards where quality was mission critical. User:AlMac| 09:10, 8 January 2006 (UTC)
Also, note that when you open any software package you agree that the company will not be held responsible for any damage caused to you or your business even as a direct result of defects in their product. If car makers could be assured that they would not be sued, the car defect rate would be as high as the software defect rate. The lack of responsibility leads to, well, irresponsibility. StuRat 09:39, 8 January 2006 (UTC)
In any company, employees can make mistakes, sometimes very expensive or embarrassing ones. How companies deal with this is rightly a secret: between themselves and the employee, and generally dealt with case by case. Some companies punish those who make mistakes, but others have learned that this only encourages ingenuity in hiding them until they become more serious. In some companies, corporate embarrassment is severely punished, by sacking a senior person in charge. Software companies generally learn that if you sack every programmer who makes a mistake, then you won't have any programmers. Notinasnaid 11:14, 8 January 2006 (UTC)
As a computer programmer myself, I can tell you most of us would very much want to thouroughly test and fix our software, but management budgets and schedules don't allow this. So, blaming the programmers is a bit like blaming a homebuilder who you told to build you a mansion in a week for a thousand dollars. StuRat 11:50, 8 January 2006 (UTC)


Agree! Error is corporate made. Head, sales, boss and employees are on par with customers to tolerate errors.
If you want to get rid of this, try designing a product that customers shall pay its price, including enough time for reflexion about security and design before programming, and enough testing while programming and again after.
By the time, other companies have won the market, their product is cheaper, full of bugs, but! it was available before.
There is no fatality. Your product must show a high level of quality and, more, be in advance (techniques, marketing, design, features). Look around for such, maybe you purchased one and paid the price. --Harvestman 20:10, 9 January 2006 (UTC)

How do solar sails work ?

I understand that light hits the sail and is reflected back off the sail. My question is how masslesss photons can exert any pressure on the sail. When I use F = ma to calculate the force, even if the acceleration is from the speed of light in one direction to the speed of light in the reverse direction, I still get a force of zero for a massless particle. What am I missing ?

There is a device with a similar function, a "fan" inside an evacuated glass container with one side of each blade painted black and the other white. The difference in reflectivity causes the fan to rotate when in the light. This might be a purer example of the effect I'm asking about, since solar sails will also catch particles in the solar wind which do have mass. StuRat 08:03, 8 January 2006 (UTC)

The "fan" (Crookes radiometer) seems to work on something completely different from the solar sail. The light mill needs gas particles to work (i.e. a partial vacuum, not a total vacuum). --AySz88^-^ 08:27, 8 January 2006 (UTC)
According to solar sail, the pressure comes from radiation pressure. Have a look at that article; it explains how it works. enochlau (talk) 08:39, 8 January 2006 (UTC)

I've read that article, and it really didn't explain it, just gave a formula to find the strength:

It may be shown by electromagnetic theory, by quantum theory, or by thermodynamics, making no assumptions as to the nature of the radiation, that the pressure against a surface exposed in a space traversed by radiation uniformly in all directions is equal to 1/3 the total radiant energy per unit volume within that space.
For black body radiation, in equilibrium with the exposed surface, the energy density is, in accordance with the Stefan-Boltzmann law, equal to σT/3c; in which σ is the Stefan-Boltzmann constant, c is the speed of light, and T is the absolute temperature of the space. One third of this energy is equal to 6.305×10T J/mK, which is therefore equal to the pressure in pascals.

I'm really looking for an intuitive explanation. I suppose if it involves quantum mechanics or something else inherently non-intuitive, I will just have to accept it without understanding it. StuRat 09:09, 8 January 2006 (UTC)

Photoelectric effect. It's not really the same context as a solar sail, but it ends up ejecting electrons (which bear mass) - so it is ultimately the same principle. F=ma is an incomplete formula: it is incompatible with quantum mechanics. I myself am searching for a better formula (I have a hunch that one exists) that will account for the force a photon exerts on a mass, but also compatible with classical mechanical situations. (ie. breaking down the "mass" into different components). Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 10:02, 8 January 2006 (UTC)

Energy is mass in a different form. So if mass can propell something, energy should also be able to do that. But mass can only propell something when it has energy (which it then transfers to the object being moved). So energy is the only thing that is needed, I'd say. Which makes sense of course. What happens to a photon that hits a sail (or anything else for that matter)? Does it lose its energy=mass and thus get transformed into something else? I understand from photoelectric effect that photons (being electromagnetic radiation) knock electrons out of the material they hit. But then the sail would be 'eaten away'. DirkvdM 10:17, 8 January 2006 (UTC)
Having electron constantly leaving the material does seem like a problem, unless they are somehow created by the photons which hit. I didn't think the photon lost any energy, but just changed it's direction, like a perfectly elastic ball bouncing off a wall. Also, I don't see energy as equal to mass but rather as something that can theoretically be converted into mass. As far as I know, this doesn't happen in a solar sail, however. StuRat 10:22, 8 January 2006 (UTC)
I thought about it a bit more, and I suppose losing electrons at a sizable portion of the speed of light would accelerate the object to a similar portion of the speed of light (although this might take thousands of years). A large positive charge would seem to build up on the solar sail, however, as it becomes deficient in electrons. I would think this charge would build to a point where it would suck any ejected electrons right back down. StuRat 10:43, 8 January 2006 (UTC)
It'll probably generate current and the electrons simply go to another part of the sail (which then the current replaces the electrons the metal atoms lost). The energy would then probably eventually contribute to the driving force on the sail anyway. Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 15:40, 8 January 2006 (UTC)
I don't see how this solves the problem of the sail taking on a net positive charge and thus a huge attraction for any electrons which manage to get free. StuRat 20:51, 8 January 2006 (UTC)
Solar cells use the photoelectric effect and don't build up a huge static charge or something, so I assume it doesn't happen to solar sails. One thing I want to ask though is, does photosynthesis use the photoelectric effect, (roughly, except with a light-sensitive pigment), or is it something else? Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 06:26, 9 January 2006 (UTC)
The difference is that solar sails are in a vacuum, or near vacuum, so can't easily replace the missing electrons with more from the environment around them. StuRat 08:47, 9 January 2006 (UTC)
As I was aware, photovoltaic cells replace their electrons with the current behind it (it merely passes on an electron, and receiving one back, and the true flow of movement is energy) when it is generated. I would assume solar sails would undergo the same process. Elle vécu heureuse (Be eudaimonic!) 22:39, 9 January 2006 (UTC)
In order to have any thrust, the electrons must be ejected from the solar sail. If so, positive charge builds up, if not, no thrust. StuRat 02:18, 10 January 2006 (UTC)
The problem is that I think the relationship between mass and energy in correspondence to force isn't e=mc^2, but something entirely different, based on the entire premise that say, a body that isn't moving doesn't bear any force anyhow, but of course, holds energy. Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 10:23, 8 January 2006 (UTC)
It is true that photons have zero mass (zero rest mass, to be precise), but they do have momentum. This allows you to use conservation of momentum to calculate the radiation pressure. You may think that momentum implies mass, but physicists say that this is not true (see "Does light have mass?" on Physics FAQ). --Heron 12:03, 8 January 2006 (UTC)

I'm just a lowly engineering science-type guy, but this just F=Ma with the solar particles, and perhaps radiation (the wave-particle thingie). Solar sails are a thing of the past, I think good old ion engines with nuclear power are way better! --Zeizmic 17:10, 8 January 2006 (UTC)

Obsolete before they have even been made to work yet ? StuRat 20:51, 8 January 2006 (UTC)
The same might happen to ion engines and anything that follows (for quite some time). These things would take so incredbly long to get to the even nearest star (if that is the goal) that before they're well underway a better technology will have been developed that will over take them. Only when we've got a technology that would take the craft to its destination in a few decades will it be worthwhile to actually send it. Which is not a very strong incentive to develop anything at all, alas. DirkvdM 12:06, 9 January 2006 (UTC)
Yea, Voyager might be more interesting as a time-capsule than to communicate with aliens. When we go pick it up in a century or two it will be an interesting item for some musuem. StuRat 02:22, 10 January 2006 (UTC)

The problem comes from thinking of rest mass as the real mass. The relativistic mass is the real mass in terms of actual behavior. But it varies according to the relative speed of the object so isn't as useful in terms of teaching students or of defining invariable qualities of particles, so rest mass gets called the real mass and the actual behavior of objects becomes more mysterious. But's its easier to teach and they aren't going to become physicists anyway... WAS 4.250 03:11, 14 January 2006 (UTC)

hEARing

I believe we have body activity patterns we have subconsiously learned to ignore.

What causes me to intermittently hear my heart beating out of my right ear? (I am assuming that is what I am hearing.) Is that a symptom of some ear problem?

I went for months without this distraction, then had it on and off a couple days, typically hald a dozen short sessions of perhaps 1/4 hour worth, then a rest for a while, then another session, and now I have peace and quiet again. I not remember my left ear hearing this in ages.

I will be age 62 this Feb 8 and fear that as our bodies grow older, they develop new aliments. I sure hope this nuisance is not going to be another of those new ailments, I will have to learn to live with. User:AlMac| 09:17, 8 January 2006 (UTC)

Just about everyone could hear their own heartbeat in complete silence. Hearing your heartbeat at normal background sound levels may be a sign of high blood pressure, however. I suggest you get a BP cuff and take your BP the next time this happens. Also take some "baseline" readings when you don't hear this sound, to see what your normal reading is. Spikes in BP may be caused by certain conditions, such as sodium sensitive hypertension. It would be a good idea to consult a physician, as untreated high BP can be quite dangerous. StuRat 09:32, 8 January 2006 (UTC)
I'm no expert at this at all, but isn't high blood pressure a symptom rather than an ailment? For example for blood clots? To continue with this thought, I can imagine that if a tiny clot would end up in a small blood vessel near the inner ear that could have such an effect. A remedy might then be taking aspirin (an anticoagulant). Or alcohol, for a happier alternative :) . DirkvdM 10:29, 8 January 2006 (UTC)
No, I think hypertension, AKA, high blood pressure, may be considered an ailment by itself. It could also be viewed as a result of bad diet, obesity, age, etc., and a cause of things like stroke. StuRat 10:47, 8 January 2006 (UTC)
Have you held a finger to your neck to see if your pulse has the same rhythm as the beat in your ear? They could be unrelated. Black Carrot 23:54, 8 January 2006 (UTC)
Why would they be unrelated ? I don't think he has grown a 2nd heart in his ear, LOL. StuRat 08:45, 9 January 2006 (UTC)
What else could cause a pulsating noise (at roughly the heart's frequency)? I can't think of anything. Very slow brainwaves (f=1Hz)? :) DirkvdM 12:09, 9 January 2006 (UTC)
Brainwaves? Anyway, it's an easy enough thing to check, and it would make a big difference if it turned out not to be on the same rhythm. Black Carrot 13:13, 9 January 2006 (UTC)
It has not happened again since shortly before Black Carrot's suggestion. StuRat is perfectly correct to imply that I may have a problem with over-weight and bad diet and I forget the other thing. This picture of me is from a few years ago. I have put on a bit of weight since then. User:AlMac| 07:08, 10 January 2006 (UTC)

spiders : how do they build some nets?

I need to make a question to a spiders expert because I need information on how some spiders build their nets, everybody speaks about nets and spiders but nobody actually explain how some extraordinary patterns are made! I saw 9 metres nets long in orizontal direction with nothing in between!!! How can they build it???We use elicopters but they do not! waiting for answer Raffaele Serafini Veneto-Europe

I think you mean webs. There are also some spiders which make portable nets, but I don't think that's what you're asking. Each species has a different technique, but here's a general overview of web design:
1) First they drop from the highest point and leave a non-sticky line behind. They then anchor this at the lowest point, too.
2) They then climb back up the line and repeat another line but anchor it at the center of the orignal line as well as at the top and bottom. This new line might be rotated, say 30 degrees, about the center from the first line.
3) They repeat this until they have all the axial lines in non-sticky silk.
4) They then connect some cross supports with non-sticky thread, maybe 2 or 3 concentric sets.
5) Now it's time to add the sticky silk in a radial pattern between the supports.
6) Depending on the spider, they might go to the center or to the edge to wait for a victim. Once they feel vibrations on the non-sticky lines, the follow them out to the prey and kill it.
StuRat 11:41, 8 January 2006 (UTC)
Do they use those portable nets for their shopping? :)
There is a spider that carries a net around with it's front two legs, and wraps it around it's prey, as opposed to having a fixed web. StuRat 02:05, 10 January 2006 (UTC)
The biggest web I ever ran into (literally) was in Australia, where I went to the side of the road for a piss and bounced off something. Which turned out to be a huge web (and was still intact after me bouncing of it!). I didn't wait to see the spider as you may understand. That was about 3 m across. But 9 m? The biggest Web of them all, however, is of course World Wide. :) DirkvdM 12:18, 9 January 2006 (UTC)
Oh, and then there is another little bit of trivia about spider webs, namely how they perform under the influence of several drgus. Cafeine and sleeping pills (opposites, ironically) turn out to be the most disruptive drugs. See , and . But I'm getting a feeling we've already had a similar thread. DirkvdM 12:29, 9 January 2006 (UTC)
Some spiders can also spool a thread of sticky silk into the air, and air currents will carry it for some distance until the thread catches on an object. This is how many spiders stretch long, single threads across a horizontal distance. Small spiders can also "balloon" on silk parachutes that float on the wind. TheSPY 16:20, 9 January 2006 (UTC)

Caves

Section title added
WHICH IS THE OLDEST CAVE IN THE WORLD`````````

Please don't use all CAPITAL LETTERS; it looks you are shouting. I don't think that there is any 'oldest' cave; many caves have existed since prehistoric times. smurrayinchester 14:11, 8 January 2006 (UTC)
Probably since the Earth was formed too. Elle vécut heureusement toujours dorénavant (Be eudaimonic!) 14:49, 8 January 2006 (UTC)
It's possible he means the oldest cave that's used as a tourist attraction. Black Carrot 20:11, 8 January 2006 (UTC)
Er, you mean, the cave that's been a tourist attraction for the longest time? =P —Keenan Pepper 23:08, 8 January 2006 (UTC)
Possibly. Caves do grow over time, though, they don't all date back to the formation of the earth. They can be formed by underground streams, for instance, sweeping away more and more material over the years until a set of caverns forms. Also, not all caves start out open to the air. So, they have at least four birthdays: the day they became big enough to be considered caves, the day a hole to the surface opened(possibly the same), the day they were discovered, and the day people started making money off them. --Black Carrot 00:07, 9 January 2006 (UTC)


to fresh users : don't try adding ``````'s to sign. Just tildes. It is on some different key or uses some combination with the shift, ctrl ot alt key. '`````Harvestman 19:05, 9 January 2006 (UTC)

sound

if all objects create sounds by vibration then what is doing the vibrations?

Not a true assumption. Could you clarify? --Zeizmic 15:17, 8 January 2006 (UTC)
Please see sound. -- Rick Block (talk) 18:51, 8 January 2006 (UTC)
Any part of an object can vibrate. That vibration pushes on the air/water/etc, which makes that vibrate. The vibration of the air makes your ear drum vibrate, which is how you hear. Black Carrot 20:15, 8 January 2006 (UTC)

Some other form of energy creates the vibrations initially. For example, during an explosion chemical potential energy is changed into various other forms of energy, including sound vibrations. StuRat 20:41, 8 January 2006 (UTC)

If a solid object gets hit by something it will move with it ('go with the flow'). If it 'hangs loose' (sorry about the analogy) it will fly off. But if it is fixed somehow it will bounce back. Until it reaches the furthest point in the other direction, upon which it will move back again. Etc etc. If the object and the fixation point are both sufficiently stiff this back and forth movement will go on for quite some time, enough to stabilise in a regular vibration (frequency). The air around it will then start to move with it. Which in turn pushes the air around that, causing the wave to propagate and eventually possibly reach an ear. And if the frequency is between (roughly) 20 and 20 thousand Hz (vibrations) we will perceive it as a sound. Hope this is what you meant to ask. :) Oh, and the thing that hits the object might itself be a sound wave. An object will have a tendency to vibrate at a certain frequency (or discrete multiples of it). If the sound that hits it has such a frequency the object will start to vibrate along (sympathetic vibration or resonance). DirkvdM 12:46, 9 January 2006 (UTC)

HTML tag for verdana text?

I'd like to make the text on a HTML page appear in Verdana (obviously only when installed on the PC of the viewer). '' and '' don't work, and a Google search yields nothing. Can anyone help me?

It's been many years since I last touched the <font> tag but the first should work, although you might like to capitalise the V in Verdana. It is now better to use the <span> tag as follows: <span style="font-family:Verdana">Text</span>. enochlau (talk) 15:53, 8 January 2006 (UTC)
(After edit conflict...) There's no HTML tag for Verdana, but you could use CSS:
 <span style="font-family:verdana">Your text</span>
Putting in an alternate font for users without Verdana would be a good idea too:
 <span style="font-family:verdana,sans-serif">Your text</span>
Or if you plan to use Verdana in a couple places, e.g. in the title of the page and in each paragraph of content, you'd be better of using straight CSS without the style tag. In the <head> of your HTML page:e
  <style type="text/css"><!--
  h1 { font-family:verdana }
  p { font-family: verdana }
  //--></style>
and then code the body of your HTML page as usual:
  <h1>Page title</h1>
  <p>This is some text that will appear in Verdana.</p>
  <p>Here is some more text also in Verdana.</p>
Hope that helps, David Iberri (talk) 16:01, 8 January 2006 (UTC)

Thanks for your response, but none of those seem to help; I should have mentioned that the text I want to Verdana-ise is in a table -- meaning I want the whole table to be in verdana. FONT FACE works if I start it during a cell, ie ''<td><font face="verdana">Red motorcar</td>'', but when I write /TD it automatically closes the FONT FACE tag, too (meaning I'd have to type it around 250-300 times).

Then wrap the whole table on a div:
<div style="font-family: Verdana, sans-serif"><table>
 ...
 </table></div>
Don't forget the "sans-serif" part, which is used when the Verdana font is not installed. --cesarb 16:38, 8 January 2006 (UTC)
Or define the <td> tag as Verdana:
 <style type="text/css">
 td { font-family:verdana }
 </style>
enochlau (talk) 17:07, 8 January 2006 (UTC)
  • I think the answer you are looking for is: there isn't a reliable way to set all of a table's font faces with one tag using just HTML. I believe in Internet Explorer you can put the entire TABLE element inside of a FONT tag, but I don't think this works in most browsers. Instead you have to either set the FONT for each bit of text in the table or you have to use CSS. --Fastfission 17:16, 8 January 2006 (UTC)
  • You may find a better answer to your question in Wikibooks. Just check here. --JB Adder | Talk 05:21, 10 January 2006 (UTC)

What?!

What kind of a sick freak would deface a nativity? Do they have no respect for christ at all? Is this a treatable mental illness? Or are some people just beyond hope?--63.22.111.181 17:33, 8 January 2006 (UTC)

Maybe. --Fangz 19:32, 8 January 2006 (UTC)
Could you be more specific? Who defaced what nativity when, and how? Most likely, it is not a mental illness, and as such does not require treatment. If they defaced a display, it seems reasonable to suppose that no, they don't respect the person being honored by it. And I suspect many people don't define 'hope' the way you're using it here. --Black Carrot 20:21, 8 January 2006 (UTC)
We live in a world of people with a wide range of impaired judgement, like kids who turn over gravestones in cemetary of some sob-group of society they not like, for reasons they cannot explain to anyone who not share their dislike. Often this is a problem of a lack of education, or an unwillingness to be educated on diversity topics. Start off with the assumption, that for some people, nothing is sacred. It then follows that they see nothing wrong with terrorism, hijacking airliners, murder, drug abuse, respect for other people's religious icons. User:AlMac| 20:47, 8 January 2006 (UTC)
Not intending to start anything here, and I agree that it's a shame and disrepsectful, but knocking over some mannequins is a very common form of youthful vandalism, can be hilarious, and is not on a par with any of the things you mentioned. And drug abuse? I live in a town with some very socially conscious hippies who would take exception to being lumped into a category with terrorists, or even nativity-defilers. Point is, this is not the place to debate morality. The questions asked are not answerable, and this whole part ought to be deleted. Just the facts, ma'am. Bethefawn 1418, 8.1.06

There are some who feel the use of public dollars to display items in support of any one religion is wrong, and might vandalize it for that reason. I think it's wrong, but wouldn't go that far. StuRat 21:22, 8 January 2006 (UTC)

Drug abuse in this context? (What is the context anyway?) What does that mean? Forcing drugs down other people's throats? And how many questions can I ask in a row? DirkvdM 12:52, 9 January 2006 (UTC)


What does "defacing a nativity" mean? deeptrivia (talk) 13:59, 9 January 2006 (UTC)

It could mean vandalize a painting that represents Jesus, his mother, and so on, just after birth. --Harvestman 19:02, 9 January 2006 (UTC)

Weather

Why does summer in Ontario on Lake Superior feel hotter than in the prairies even though the temperature is not as low?--64.231.193.87 18:42, 8 January 2006 (UTC)

Humidity and/or wind speed ? StuRat 20:32, 8 January 2006 (UTC)
Well, if the temperature is "not as low", that means it's hotter, which is why it would feel that way. GeeJo (t) (c) 04:22, 9 January 2006 (UTC)

Hydrated to anhydrous

What are some ways to change a hydrated salt anhydrous?

Heat it. Don't heat it too much though, as that will cause the salt to decompose. --Shanedidona 19:24, 8 January 2006 (UTC)

Some salts have greater affinity for water than others. I think that if you stored the hydrated salt together with anhydrous, high affinity salt, eventually most of your original salt would be anhydrous. ike9898 20:16, 8 January 2006 (UTC)

Miscellaneous Questions

I have several science related Miscellaneous questions:

1) Bullets travel faster than sound, right? So why don't we experiance a sonic boom, something like two bangs one for the gunpowder and another shortly after for breaking the sound barrier?

The bullet breaks the sound barrier while still inside the gun barrel. StuRat 20:25, 8 January 2006 (UTC)
I don't know a lot about sonic booms, but believe you only hear one as the object passes you. So, if there was one, the person firing the gun wouldn't hear it. As the bullet passes someone, if there was an audible sonic boom, it would be heard before the gun firing. The boom reaches you when the bullet reaches you, and the bullet is traveling faster than the sound of the gun. But would there be enough of a time delay between them to hear the difference? --Black Carrot 20:43, 8 January 2006 (UTC)
The first 20 minutes of Saving private Ryan are supposed to be very realistic and there the soldiers hear a whooshing or whistling sound when the bullets pass by. Maybe the bullet's speed drops below the sound barrier after a while. Or maybe it is too small to make a noticeable sound. DirkvdM 13:02, 9 January 2006 (UTC)
You do, but "crack" as the bullet passes the sound barrier generally blends with the report of the rifle and gunpowder explosion itself to be indistinguishable. Remember, the bullet stops accelerating the moment the hot gases cease to act on it (i.e. milliseconds after it leaves the barrel), so the two events are closer together than your ear can distinguish. It's a major problem when trying to create a quieter weapon, so supressed guns either use special subsonic ammunition or ports in the barrel that reduce the velocity of normal ammunition below the speed of sound. The sonic boom is much less than that created by an airplane simply because the bullet is several orders of magnitude smaller and therefore displaces and compresses much less air as it passes its own shockwave. Night Gyr 01:34, 10 January 2006 (UTC)

2) Would there be a light barrier eg. in theory if an object of some sort exceeds the speed of light (although not possible) would there be some kind of explosion of light as it build up aroung the object, this is all merely theoretical.

Actually, it is possible (though not in a vacuum). See Cherenkov radiation. GeeJo (t) (c) 04:16, 9 January 2006 (UTC)

3) Is 100% insulation of an object possible? eg. a means of an object forever retaining constant temperature? and on the other extreme is 100% heat conductivity possible?

Nothing can be 100% insulating. - Akamad 01:55, 9 January 2006 (UTC)
Aerogel comes close, though. Anyone know the cost per cubic meter for it? Tzarius 10:47, 9 January 2006 (UTC)
Nothing is pure or absolute. Nothing is ever 100% anything. (This could turn into a very long philosophical discussion :) .) DirkvdM 13:02, 9 January 2006 (UTC)
I'll call your bluff: Bullsh**! What now? I didn't think so! ;) Black Carrot 00:04, 10 January 2006 (UTC)
I think there are many absolutes, like absolute zero. StuRat 01:58, 10 January 2006 (UTC)
Shouldn't that article be called 'zero temperature'? It suggests that there are no other absolute zeros. I'm going to defend that there are none at all, but that's philosophical. In our reality they make perfect sense. Like classical mechanics still makes perfect sense for everyday life, even though modern physics has proven it wrong. Anyway....
You may define zero temperature and use it as a basis for scientific calculations because that happens to work, but can you achieve absolute motionlessness (which it really means) in the real world? Take distance. There, you can even go into the negative numbers, but that doesn't represent any real thing. Same with 0 m. That is a mathematically completely sound thing. But nothing in the real world can be 0 m long - it wouldn't exist (in our dimensions anyway). Mathematics is the only area that has absolute truths (the philosophical bit I was really thinking about), but only because it defines its own world. Which we can use to analyse the real world, but that doesn't make it equal to reality. Actually, I think mathematics is the formalisation of the way we see the world. We've figured out how are spectacles work, but that does not mean we can take them off. So we can never see the real world and therefore not find any absolute truths that might be out there, except the ones we impose on it.
See also thinking pc and quantum mechanics below.
Black Carrot, you didn't think what? I only go through this page once every morning, so don't expect instant replies from me. And did you mean to say 'bullshit' perchance? If so, why didn't you say it? And if you don't want to say it, then why do you (halfheartedly)? Make up your mind. :) DirkvdM 06:33, 10 January 2006 (UTC)
Absolute zero is its name. There are several systems of temperature measurement, and there used to be more, so this is in comparison to them. 0C is the freezing point of water, 0F is god knows what, and 0K is the absolute zero point of temperature. And I believe it is in fact possible to reach absolute zero eventually, through radiation of heat. Feel free to correct me on that last point.
0m does represent something, as the result of a sum of lengths or vectors. It represents a lack of resultant motion. So, if you move 1m forward, 3m to your left, 4m to your right, 1m back, and 1m to your left on a flat floor, you have moved 0m total. True, it won't be exactly 0m if none of the other measurements were exact, but that's a fault of the precision of measurement in general, not a problem with the practical concept of 0.
There are plenty of things that can be 100%. 100% of my class is in the age range 16-19, 100% of the people in this room right now are of the species homo sapiens, 100% of the particles in the square foot of air in front of my face are less than 1 inch across, I have occasionally gotten 100% of the answers on my homework correct. True, there are some things that can't be made 100%, like (at least for now) it's impossible to keep the human race 100% male for very long, but there are some things that undeniably can. That's the philosophical side of my argument. The actual wording was chosen in the wild, overpowering excitement of the moment (irony, in case you were wondering), and was an imitation of the sh**-talking I've occasionally heard. The asterisks were because we're supposed to humor those who think the young people viewing this page don't know and/or shouldn't see such words in full. It wasn't in the least half-hearted. Holla back, yo. --Black Carrot 20:27, 11 January 2006 (UTC)
I prefer logical language, so to me 'absolute zero' should mean just that, a mathematical entity. If it's already been reserved (in practise) for absolute zero of one specific unit, that's too bad. I dare you to find a source that this absolute zero (or any other one) has ever been achieved. An absolute lack of temperature would mean total motionless. Where there is no motion and no time and not anything. It is (by definition?) non-existent.
As for 0m, you already point in the direction of one flaw. You'd have to make the measurements absolutely precise. With mathematical precision. Try finding measuring stick and/or method that can achieve that. If you use something material then that consists of atoms. Which have size. So the measuring goes in steps and can only be absolutely precise if the measurement you wish coincides precisely with a physical measuring length (a chance that approaches zero). But what I meant is that nothing can be 0m. Or 1m for that matter. Those are mathematical values that do not exist in reality.
About the 100% examples. I can't get the counterargumentation right in my head (though it's in there somewhere) and I don't have much time now, but it's got to do with you defining the entities you measure (as in mathematics).
Holla back, yo? That's a lingo I don't talk. :) What does it mean? DirkvdM 10:22, 12 January 2006 (UTC)
Logical language? oxymoron :) Seriously, though, there's no reason the phrase can't be used for lots of things, if that's the way people want it. Just look at all the disambiguation pages on Misplaced Pages. Venus has about 25 meanings, but nobody has trouble using it. Absolute zero doesn't really work as a name for the mathematical representation of nothing, though, because that already has a shorter name - zero. As for its practical existence: I don't think it has been achieved yet, and I would trust someone who works with it to tell me it can't be. However, I am not at all certain based on what little I know of it that it is impossible. It seems that, if matter is capable of radiating away heat in the form of electromagnetic energy (which it is), and if energy is quantized (removing the possiblity of asymptotic loss of heat), a particle left on its own, with no source of additional energy, would sooner or later radiate away all of its own. A lack of temperature BTW, according to the article, doesn't exactly mean total motionlessness, and I very much doubt it is equivalent to timelessness.
As I said, the practical problem of exact measurement (a very real difference between pure math and applied math) is not the issue. The question is whether 0m exists, and it does. It's hard to say whether any particular resultant motion equals 0m, but it exists. As to length, to say that nothing can be 0m long is to define the term. If I tell you there are zero people in the room other than me, that is an exact statement of amount. If I tell you there are zero square meters of cloth left to work with, although that would be an odd way of putting it, it would still be true. I wouldn't mean there might be anything between .000001 and -.000001 square meters left, I mean we've actually used it all up and need to go out for more. To say that no thing can be 1m long is plain wrong, unless it turns out that the universe exists in discrete intervals, of which 1m is not a multiple. If you're saying that the symbols 0 and m, when put together, represent nothing but an abstract concept, it seems you miss the point of putting them together in the first place.
Take your time. We've got a few days before this moves to the archives.
Quite elementary, my dear DirkvdM. You see, 'Holla' is a phonetic rendering of the word holler in an English subdialect referred to by some as 'blackinese'. To 'holla' or to 'holla back' means to respond, possibly later on by phone, and 'yo' is a barely meaningful word that need not be translated, like est-ce que in French. It is either a corruption of the English word 'you' or a loud nonsense syllable similar to the British 'oy', intended either to get someone's attention or as a greeting(similar to 'hi'), depending on context. In this case, any or all could fit. Here, it mainly serves to provide emphasis, and cement the sentence's mock-ethnic origins. In total, including connotation and idiom, the phrase 'Holla back, yo' can be roughly translated as "Get back to me." --Black Carrot 20:34, 12 January 2006 (UTC)Black Carrot 00:00, 13 January 2006 (UTC)
Well let me holler at you once again, dear Carrot.
"... with no source of additional energy, ..." Ah, but there always is one, unless the surrounding material (!?) is also at 0 K. Which begs the question. You might eliminate the surrounding material by suspending it in vacuum (absolute vacuum ??), but still holding it together somehow. With what? If not matter, then energy. Without transferring any energy to the material? Ultimately only an absolute vacuum would have no motion. But that's nothing (by definition).So doesn't exist. Which is why absolute vacuum can't exist.
The zero cloth and zero people don't exist, do they? All you say is that something does not exist. Which is my point (sounds a bit lame, but true nonetheless).
The universe does indeed exist in discrete intervals, or so quantum mechanics tells us, I believe. But that's less of a principal matter than this (the theory could be wrong). But you still can't have anything that is precisely 1 m long, in terms of mathematical precision. You may get incredibly close (by human standards, but that's also not a principal perspective), but that's not what this is about. I could always add a few decimals and demand you get that much closer. The point is I could always do that.
About the 100% thing. Your mentioning a discrete universe gave me a different angle. By defining people and such as entities you introduce 'discreteness'. You define discrete entities and that makes it work. But these only make sense to you. Well, most of the time anyway. Let me use an old example in philosophy about a ship (I forgot the name). Everytime a part was replaced someone kept it. After a time all the parts have been replaced and the guy puts them all together. The traditional question is which is the original ship. But I ask how many ships there are. The concept of entity has broken down. It's an illusion that 'works' most of the time in real life. But that does not make it a principal thing in reality. Hmmm, stillnot satisfied with that explanation. There has to be better way to say this. But maybe you start to catch my drift (speaking of ships :) ). DirkvdM 11:15, 14 January 2006 (UTC)
Don't you think you're stretching a bit with some of that? Why must it be 'held together'? I was thinking of a lonely atom, floating around in space, where it shouldn't be in the least difficult to isolate it from its surroundings. And emptiness, unless the entire universe ceases to exist, has a very definite existence, as the lack, in that area, of all those materials we hold so dear. It's like saying a hole in the ground doesn't exist just because, if the entire world were a hole, there's be nothing left.
No, your point is, "Those are mathematical values that do not exist in reality." This refers to both things in the previous sentence: 0 and 1. The measurements 0m and 1m, however, do exist. One indicates a lack of whatever's being measured, the other indicates the presence of 1 meter's length of it.
That's true(as best I know), and irrelevant. I said above, "As I said, the practical problem of exact measurement (a very real difference between pure math and applied math) is not the issue. The question is whether 0m exists, and it does." You had added in the 1m yourself, drawing a parallel where it turns out none exists. As a matter of fact, reading over all of it again, I think the 0m thing itself was only introduced as a parallel to 0K. However, our discussion thus far seems to have revealed that they aren't similar in the way you'd hoped.
That story reminds me of the tin man from the wizard of Oz. His limbs got hacked off one by one (accidents caused by a witch, if I recall) and replaced with metal ones. Finally, both his arms, both his legs, his head, and his torso were all metal. Of course, in that example it's easy to tell what's wrong. A better example might be one from either God's Debris or The Religion War, involving the battles over Jerusalem. The difficulty was defining what about that particular point in the universe made it special. The position? That changes drastically by the second. The dirt? Surely there's enough of that to go around. However, I feel neither captures what you're trying to say. I think I've got a handle on it, though, and despite its good points, I think it's totally wrong. Tell me if this helps:
  • Mathematics, though it's defined by us (therefore self-consistent), and though quite a bit can be implied by it that can't actually be done in the real world, the real world isn't alone in that. There are plenty of things implied by one part of mathematics that even another branch of mathematics can't handle, which is why we have so many. Trying to describe the fraction 1/3 in the form of a decimal, for instance, or trying to describe sin x using only non-trigonometric functions. Both can be infinitely approached, neither is possible. There are many other examples.
  • There are plenty of places where mathematics does sync up with the real world perfectly, which is why we use it. There are plenty of places where 100% is perfectly achievable, and certainly at least exists, especially in the fields that gave birth to it, rudimentary statistics and probability. Ex: If I flip a coin, there is a roughly 50 per cent chance it will land on heads. If, however, I drop a red ball, there is an exactly 100% chance it will land on its red side. If I drop it over and over again, there is no doubt it will land on red 100 per 100 times. --Black Carrot 23:35, 14 January 2006 (UTC)
I don't know if this is true but I seem to remember hearing that some superconductors can be perfect heat conductors. – b_jonas 20:41, 12 January 2006 (UTC)

4) What are quarks made of? And then what is that made of and then that, etc?

I think quarks are made of strings, according to current theory. I don't think current theory goes any deeper than that. StuRat 20:25, 8 January 2006 (UTC)
By definition (if you take the word literally) the smallest building block is the atom. DirkvdM 13:02, 9 January 2006 (UTC)

5) What effect does the combinations of quarks have on a particle eg. rather than 2 down and 1 up two bottom and a top, and if i had a rod of iron one made of the first type of neutrons and then another with the second kind would there be a visual, chemical or physical difference?

7121989 19:55, 8 January 2006 (UTC)

In answer to question 2. When you are talking about the sound barrier, its the speed of sound in a particular media. When talking about light, the speed of light in material media is of course much lesser than that in vaccum. This lesser value can be crossed. Cherenkov radiation is electromagnetic radiation emitted when a charged particle passes through an insulator at a speed greater than that of light in the medium. The characteristic "blue glow" of nuclear reactors is due to Cherenkov radiation. It is named after Pavel Alekseyevich Cherenkov, the 1958 Nobel Prize winner who was the first to rigorously characterize it. --Sayanchak 20:22, 8 January 2006 (UTC)
In answer to question 3, 100% insulation of an object isn't possible. Energy can be conveyed through matter by conduction, and through vacuum carried by photons (radiative transfer). 100% heat conductivity is possible, depending on exactly what is meant by the term. Superfluids like liquid helium are perfect conductors of heat; in their superfluid state it is impossible to set up a temperature gradient within the fluid. TenOfAllTrades(talk) 20:31, 8 January 2006 (UTC)
To answer question 5, the combination of quarks defines the type of particle. By definition, a neutron contains one up and two down quarks. A particle made up of one top and two bottom quarks–while still being of neutral charge–would be a very different beast. (Much more massive, and very short-lived.) TenOfAllTrades(talk) 20:31, 8 January 2006 (UTC)

tornados

What makes the sky change to a yellow-green hue often when a tornado is in the area? I can't seem to find any information on this . Is it a change in the electrical charges ? thank you.

After searching both Google and HowStuffWorks for the terms 'tornado green sky', I'm prepared to answer this question in full: Nobody knows. There are quite a few theories floating around, including
  • It's just like an extreme sunset(which can have a green layer), the water-heavy air combined with the right time of day refract light farther than usual.
  • It's the vegetation that's been pulled up by the tornados (made up by some guy on a message board)
  • It's a sign of heavy hail. The hail refracts the light differently from most other things, and so gives different signs, namely a green tint to the clouds and sky.
  • Something indistinct about electricity.
There seems to be some agreement, however, on under what circumstances it shows up. It shows up with heavy storms. Some claim it shows up with tornados, some say it shows up with hail, but everyone agrees it is connected in some way to especially dangerous storms. For myself, I've only ever experienced it once (luckily, my dad recognized it and got us inside), and then, it came with everything. --Black Carrot 21:38, 8 January 2006 (UTC)

properties of sand

how will sand effect the pace at which water freezes in a 0 degrees celcius freezer?

lauren--67.189.253.185 22:45, 8 January 2006 (UTC)

Well, there will be less water to freeze per volume (or weight), so a liter of sand-water mixture should freeze faster than a liter of pure water. The sand needs to be cooled too, of course, but it won't release any heat of fusion at 0°C. (Of course, if your freezer is at exactly 0°C, the water may or may not freeze at all. The presence of sand shouldn't noticeably affect the freezing point, although it will effectively prevent supercooling.) —Ilmari Karonen (talk) 22:59, 8 January 2006 (UTC)
Also, I believe sand is a good insulator, so will slow the rate at which the water temp drops to freezing. Thus, it will take longer for the center to freeze in the sand/water mixture. The sand will provide multiple nucleation sites, too, so the ice is likely to contain more crystal cells. StuRat 08:27, 9 January 2006 (UTC)
From what I can tell by Googling (such as ), the thermal conductivity of rock (which is what sand actually is, when there's no air between the grains to act as an insulator) is typically somewhere between those of water (0.6 W/K m) and ice (2.2 W/K m). So it probably depends on what kind of sand it is, really. —Ilmari Karonen (talk) 08:52, 9 January 2006 (UTC)
Actually, I would say sand is basically small particles of glass, or silicon dioxide. However, the insulating effect is due not to the specific material, but due to the elimination of convection, which would leave the less efficient conduction as the only method of heat transfer (the third type, radiation, has little effect at the small temperature differentials being considered here). StuRat 10:02, 9 January 2006 (UTC)

Ice & Water

Which cools a drink faster, water and ice or just ice?

Do you mean putting ice (and water) into the drink, or surrounding the container with ice? If it's the latter, water and ice would cool it faster. Water will ensure that the entire surface of the container is maintained effectively at zero degrees, while if there's only ice, there will be air pockets left. While the trapped air will still be at zero degrees away from the container, it would be at a slightly higher temperature at the container surface. Basically, the overall convection coefficient would be lower than the ice+water case, and cooling will be less effective. Conduction is also much better with water than with air. deeptrivia (talk) 23:49, 8 January 2006 (UTC)
A mixture of crushed ice and salt is used in an ice cream churn to cool the ice cream very fast. —Keenan Pepper 00:20, 9 January 2006 (UTC)

OK, this is an engineering question! If you want to cool your beer in a tub faster, do you just pour on ice, or do you add water as well? Every engineer knows that you just add crushed ice; you do not bother with adding tap water. Dropping in a giant ice block tends to smash the bottles. --65.92.79.213 01:18, 9 January 2006 (UTC)

I disagree. Water would increase the contact area, as mentioned above, and thus increase the cooling rate. Only if you could crush the ice to the size of water molecules (in which case it would be water) would this effect be absent. StuRat 08:22, 9 January 2006 (UTC)
Wait would it really be (liquid) water? If so, it would be liquid water below its freezing point, and would undergo a thermally identifiable melting point as it warmed. Hmmmmm... — Knowledge Seeker 09:39, 9 January 2006 (UTC)
By crushing the ice that finely, you'd be adding enough energy to it to melt (and possibly vaporize) it. So yes. —Ilmari Karonen (talk) 09:53, 9 January 2006 (UTC)
It doesn't seem to me that you'd have to raise its temperature that much. What if you cooled the ice first to a very very cold temperature and then very carefully and slowly crushed it? Inside a giant cooler? — Knowledge Seeker 10:04, 9 January 2006 (UTC)
The previous poster referred to adding tap water. In most places that would be well above the freezing point, and would certainly reduce the cooling effect on the beer at least at first, as the melting ice would absorb heat from the tap water first. However, it would be different if the water was already chilled to the freezing point and the ice well below. Then the water would only serve to conduct heat between the beer and the ice, and would increase cooling. (Disclaimer: I have not tried the experiment.) --Anon, 09:00 UTC, January 9.

Still, it sounds like a great experiment! --Zeizmic 13:04, 9 January 2006 (UTC)

I saw on a tv show once (it might have been "Mythbusters") that the fastest way to cool drinks was to use a certain kind of fire extinguisher on them (while the drinks are in a bucket or other container). Other than that, I'd say that crushed ice and salt would probably be your best bet. Flea110 22:00, 9 January 2006 (UTC)

January 9

Vocabulary on airships.

I am currently working on a translation from English to French, parts of which are about airships. I encounter some terminology issues about the parts of an airship ; I would be very pleased if someone helped me to find a good synthesis about it. For instance, a chart with the names of the different parts would be very useful, because I would be able to compare it with a French chart. Thank you for your help. --Eutrot 02:07, 9 January 2006 (UTC)

Good restaurant to have onboard an airship...Blimpie's. StuRat 08:24, 9 January 2006 (UTC)
In the absence of a chart, what words are you interested in? --Anon, 09:00 UTC, January9

User:AlMac| 11:55, 9 January 2006 (UTC)

Regarding mobile browsing

Should we have a html enabled phone to access all sites available on the web on mobile phone? I assume html enabled phones are costly. (?) Should we must have either WAP or html to browse websites? Cant we browse through GPRS? (Please reply in detail if you can) (Thanks in advance for answering)

About AOL

I recently read that AOL is still the No.1 ISP in USA. But just want to know whether all of its dial-up customers have speeds less than 56 kbps? Does the Aol's 20 million subscribers include ISDN? Is there any other dial-up faster than 56 kbps?

AOL doesn't offer dialup services faster than 56K. Broadband users access AOL over their existing Internet connection; AOL does not act as their access conduit. To the best of my knowledge, AOL does not offer ISDN services. Significantly, not all AOL subscribers connect to AOL over dialup, so total subscriber numbers do not reflect actual dialup usage. Adrian Lamo 03:12, 9 January 2006 (UTC)

Hot body radiation

What power does hot to cold radiation have vs distance? I know that is not linear (twice as far = twice as much) but I don't know which power. hydnjo talk 04:11, 9 January 2006 (UTC)

Your question is a little unclear but EM radiation falls off with the square of the distance. So if you move twice as far away from a source, it appears a fourth of what it used to be. enochlau (talk) 04:18, 9 January 2006 (UTC)
That's exactly the question that I'm asking, I thought it was the fourth power vs distance. Am I way off base with this? --hydnjo talk 04:25, 9 January 2006 (UTC)
I don't think it's the fourth power. It follows the Inverse-square law. enochlau (talk) 04:42, 9 January 2006 (UTC)
Obviously it's inverse square. Just think of maintaining a constant heat flux over the surface of sphere of radius r. P1*(4*pi*r1^2) = P2*(4*pi*r2^2) where P is the power intensity per unit area deeptrivia (talk) 04:46, 9 January 2006 (UTC)
It's 4th power to the temperature of radiation ( H = e s A T 4 {\displaystyle H=esAT^{4}} .) Maybe that's what was confusing you. deeptrivia (talk) 05:51, 9 January 2006 (UTC)
That's exactly what I was misremembering. Thanks, hydnjo talk 19:53, 9 January 2006 (UTC)
See Stefan-Boltzmann law and Newton's law of cooling too. --HappyCamper 20:07, 9 January 2006 (UTC)
Yeah, that's it. Thanks again HC. hydnjo talk 20:27, 9 January 2006 (UTC)

Wireless router in a three storied house with lots of steel beams in the ceilings

What's the best location to put the router, and what kind of router will be suitable? I've heard that because of the steel beams, a more powerful router will be required to make the signal reach everywhere. Any other tips about what to do for better internet speed and quality in this situation? deeptrivia (talk) 04:53, 9 January 2006 (UTC)

You are going to have some interference, and maybe some shadow areas. I would go with something like the D-Link B+G (?) which has both the 2 & 5 GHz, along with the cards that can pick this up. That way you are using 2 frequencies. I have great success with mine, and I put it at the top of 3 stories. Remember to use MAC security, since you will be broadcasting to the world! --Zeizmic 13:10, 9 January 2006 (UTC)
You're wrong about the frequencies. 802.11b and 802.11g both run on 2.4 ghz, only 802.11a uses the 5.8 ghz band. Night Gyr 20:14, 10 January 2006 (UTC)

WAP, GPRS & html for mobile

What does it mean when we say that a phone is html enabled? What does it mean when we say that a phone is WAP enabled? What does it mean when we say that a phone is GPRS enabled?

See Microbrowser, Wireless Markup Language, and General Packet Radio Service. -- Rick Block (talk) 05:20, 9 January 2006 (UTC)

How much does AOL's basic service cost? (after promotional months expire)

In the United States, basic service is $23.90 per month plus local sales tax. This includes unlimited time online, both via dialup and broadband connections. --Aaron 06:33, 9 January 2006 (UTC)
And in the United Kingdom unlimited dialup costs £15.99 per month including VAT, while the cheapest broadband ("Silver" - 512kbps) costs £17.99 per month. Quite a bit more expensive than in the USA, but then, most things are! Loganberry (Talk) 12:34, 9 January 2006 (UTC)

Physics problem

Hey guys, I got stuck on this one problem. If anyone can help me out, that'd be great. Thanks!

A particle moving at 10 m/s reverses its direction to move at 20m/s in the opposite direction. If its acceleration is -10m/s^2, what is the total distance that it travels?

Why are you stuck on this. It requires a readymade formula that's in your textbook. You know v,u,a and you have to find s. deeptrivia (talk) 06:55, 9 January 2006 (UTC)
Not quite. In the ready-made formula s is the distance between the point in space at which the particle starts its motion and the point in space at which it ends its motion. The total distance travelled can be (and, in this case, is) greater than s. Best approach in this case is to break motion down into two parts; first part is slowing down from 10 m/s to stationary, second part is accelerating from stationary to -20 m/s. Gandalf61 13:38, 9 January 2006 (UTC)
Oh yes, of course! I missed that! Still the same ready-made formula applied twice, though. deeptrivia (talk) 13:53, 9 January 2006 (UTC)

sun's heat

How scientists measure sun's heat? roscoe_x 09:19, 9 January 2006 (UTC)

You've come to the right place! Misplaced Pages has thousands of volunteers ready to do your homework for you. Just type your question into the Magic Answer Box (currently called 'search', but I'm trying to get that changed). Instantly, these people will give you relevant articles that you can copy directly for your assignment. No need to think! --Zeizmic 14:12, 9 January 2006 (UTC)
Try this article. hydnjo talk 20:07, 9 January 2006 (UTC)

Walking on Mars

Assuming one had an oxygen tank, what kind of suit would be required to safely walk around on Mars? Would one need a full space-suite? Mysteriousinventors 10:10, 9 January 2006 (UTC)

If reading science fiction has tought me nothing... an insulated suit, it gets fairly cold there. But not a pressurised suit. (Still, reading science fiction has also tought me that venus is rather like Florida, and I don't think that's considered correct any more). Notinasnaid 10:39, 9 January 2006 (UTC)
It would indeed need to be pressurized, as the atmospheric presure on Mars is much less than on Earth. Besides insulation, it would also need a heating mechanism, unless it was so well insulated that body heat was sufficient to keep it warm. In any case, some system for regulating temp would be needed, as you can't just "unzip it", like a coat, if you get too hot. It would need to be quite puncture resistant, as falling against a sharp rock might create a fatal gash in the suit, otherwise. The weight, although less than on Earth, would be a considerable design constraint, as a heavy suit would significantly limit travel range, due to fatigue. For this reason, an "off the shelf" space suit, designed for EVA, might not work, being designed for weighlessness and too heavy on Mars. For long outings, some source of water would also be important. A communications system would be needed, and some monitoring systems, like for temp and pressure, might also be built in. Rather than engineer any "toilet functions" into the suit, I would expect astronauts to return to the ship for that. The suit would also need some protection from UV and other solar radiation, as Mars lacks the ozone layer which protects us from those things on Earth.
So, to summarize, it would be very much like a standard spacesuit, except a lightweight version designed for a narrower range of outside temps and greater outside pressures. StuRat 11:47, 9 January 2006 (UTC)
Well, it depends on how much risk you are willing to tolerate. E.g. UV radiation is unlikely to be harmful under brief exposure. (I'm not sure about the need to pressurise. A face mask, like e.g. scuba gear, should be sufficient for breathing purposes, and less likely to tear or puncture.) If you are going on a long expedition, you are more or less certain to bring a rover or something similar along - if only to help bring back samples. The martian day is also fairly close to ours, so there wouldn't be too many huge swings of temperature, so long as you plan correctly.--137.205.236.49 12:05, 9 January 2006 (UTC)
Two different views here on whether the suit needs to be pressurized (discounting mine, which is not based on research). What is the break even point in terms of external pressure, for needing a pressurized suit? I would presume it's the point at which pure oxygen, at the lowest pressure capable of sustaining life, causes bodily injury or an inability to breath due to the lower external pressure? Notinasnaid 12:31, 9 January 2006 (UTC)
The pressure on the surface of Mars looks to be between 6 and 10 mbar (millibar), depending on the reference consulted, the weather, and the altitude . That's about 1% of the surface pressure on Earth (roughly 1000 mbar at sea level)—so yes, you're going to need a pressurized suit to breath comfortably. For reference, the partial pressure of oxygen in the atmosphere at sea level is about 200 mbar; most healthy adults can tolerate down to about half that, at least for limited periods. TenOfAllTrades(talk) 16:20, 9 January 2006 (UTC)
Once again, after all the hard work by science fiction writers, science lets us down. Notinasnaid 11:08, 10 January 2006 (UTC)

color of complex compounds

what is the color of Cu(NH)6

My guess is blue, as many copper based compounds tend to be such. I may be wrong. Elle vécu heureuse (Be eudaimonic!) 22:45, 9 January 2006 (UTC)

Or maybe green or blue-green, as quite a lot of copper compounds have those colors, too. StuRat 01:34, 10 January 2006 (UTC)

Colors of complex compounds

what is the colour of Cu(11)hexaammine --Mufleeh 11:24, 9 January 2006 (UTC)

It's blue. --HappyCamper 20:10, 9 January 2006 (UTC)

rotational motion

What is the centrifugal force

An object in motion wants to remain in motion in a straight line, unless another force acts upon it. The force acting upon it to pull it toward to axis of rotation is called the centripetal force. The imaginary countering outward force is called the centrifugal force, but this is really just a reflection of the object wanting to travel in a straight line. StuRat 11:59, 9 January 2006


thankyou what is the color of cobolthexaammine

Cell Structure of a Chicken Egg

I know that the largest cell in the human body is the female ovum (egg), im just curious is a chicken egg also 1 singular cell, cause its so big?

Yes, a chicken egg is a highly complex single reproductive cell (the oocyte) as I remember. Brandmeister 16:40, 9 January 2006 (UTC)

Um, only until it becomes fertilized and divides. It divides many times and a full-sized egg has billions of cells. —Keenan Pepper 18:18, 9 January 2006 (UTC)
It sounds as if you are saying the white and yolk are made up of many cells? Only the embryo divides so the egg is a single cell. It is different in plants the seed endosperm (similar to the yolk and white) is multicellular. David D. (Talk) 19:17, 9 January 2006 (UTC)
Wow, I never knew that. So, I think it would be most accurate to say, the yolk of an unfertilized egg is a single cell, and the white and shell are just proteins that aren't part of any cell. The cell division after fertilization only happens on a little spot on the yolk (the germinal disk) rather than the whole yolk dividing. Is that correct? —Keenan Pepper 22:53, 9 January 2006 (UTC)
BTW, our Egg (biology) article looks like it could use a lot of work. —Keenan Pepper 22:54, 9 January 2006 (UTC)
  • I don't think the entire yolk divides, rather a chicken egg contains a single cell which divides. It all depends where the DNA is contained. That being said, a frog oocyte is one big cell (about 1mm) and the whole thing divides over and over. Nrets 22:11, 10 January 2006 (UTC)

radioactivity and living things

I know that radio active materials are bad, and that they give off alpha and beta particles etc. What i dont understand is how this process damages the human body, or any living thing for that matter. What acually happens to cause cancer and other horrible side effects, physiologically and anatomically speaking?

See ionizing radiation and radiobiology. Briefly, what happens is that radiation causes breaks in and damage to DNA. Failure to repair those breaks will kill cells; inaccurate repair leads to mutations and potentially the development of cancer. TenOfAllTrades(talk) 16:06, 9 January 2006 (UTC)
Yeah, but if you get exposed to a real high dosage of radiation that can kill you in a matter of hours. I've also wondered about this once. Is that also caused by damage to the DNA (causing 'bad' proteins to be made?) or are other molecules also damaged (eg the enzymes themselves for a more direct effect)?
By the way, radioactivity isn't necessarily bad, it's just a matter of dosage. It's all around us and may even take a part in evolution because it occasionally changes some DNA (is this true?). DirkvdM 06:50, 10 January 2006 (UTC)
"radio activity is in the air for you and me" - Kraftwerk 37:38, 21 November 1975 (UTC)

solid state physics

why do a honey-comb cell is hexagonal in shape?210.212.89.5 14:04, 9 January 2006 (UTC)

Did you read our honeycomb article? Gdr 15:07, 9 January 2006 (UTC)
This is solid state physics?? —Keenan Pepper 18:07, 9 January 2006 (UTC)
Well, honey-combs have no moving parts, although bees have quite a few. StuRat 01:29, 10 January 2006 (UTC)
Lol, solid state physics doesn't mean the physics of solid things Solid-state physics--Name------------------name 18:09, 12 January 2006 (UTC)

Mimosa Tree

Hi, I am trying to find info on the Mimosa tree, please note that the name is used for more than one tree, in Italy the name refers to: and in the U.S. It refers to . I am interested in the Italian version (yellow tree). I am mostly finding info on the red tree

  • What the US name of the tree?
  • What is the official name of the tree?
  • Is there an encyclopedia article on the 'yellow mimosa' tree?
  • What climate does the tree grow in? (Is this tree suitable for SouthEastern U.S.?)
  • (far fetched) I am trying to buy this tree, where do I look and what do I ask for?

~Thank you

Our article on mimosa does not seem to have this information. Rmhermen 18:33, 9 January 2006 (UTC)
The filename says Acacia dealbata, which is linked from Mimosa... —Keenan Pepper 18:35, 9 January 2006 (UTC)
Originally from Tasmania doesn't tolerate cold temperate climates . Hardiness zones 10-11, ideal for southwest U.S. . Jasongetsdown 19:06, 9 January 2006 (UTC)
Correction: Looks like it may actually need even warmer temps than most of S.E. U.S. . Something tells me that if you can grow it in southern U.K. it has a broader range than 10-11 though. In any case there are numerous sources on the web to buy it. Jasongetsdown 19:14, 9 January 2006 (UTC)

Thinking PC

I played Starcraft (mission for protoss, where I should defend a temple). I had invisible dark templars but soon noticed that zerg brings to me the overlords, which are detectors. Then the temple was attacked by mutaliscs, a zerg flying units and the templars couldn't do anything against them. Is this a demonstration of a fact that PC is really thinking? That it has AI etc? 195.150.224.238 16:31, 9 January 2006 (UTC)

It's a demonstration of StarCraft's AI, but that should not be construed as the PC independently "thinking". It's one of a series of preprogrammed checks, probably akin to:
If I die to invisible units, send detectors.
If opposing units are ground-attack only, send air-to-ground units.
Hope this helps. — Lomn | Talk / RfC 17:07, 9 January 2006 (UTC)
You could say that the way a game reacts to your choices is a basic kind of AI, but I wouldn't give the game designers too much credit. Games like StarCraft usually operate by following predefined behaviors. One behavior might be, if the human player builds invisible units, build overlords. Some games will "cheat," in other words the computer player will know you have invisible units even if a human player in the same position might not. This does not make them intelligent, just more knowledgeable.
Another way to put it would be: don't confuse logic with intelligence. Jasongetsdown 17:12, 9 January 2006 (UTC)
A lot of stuff that is called intelligent is just the above but bigger. The term AI is often used for machines with huge databases full of knowledge that the designers have put in. But that is the designer's knowledge, not the machine's. True intelligence would be when a machine gets only a set of general rules that have nothing to do with the outside world and could then apply those rules to info it gets through sensors to build its own image of the world and then use that to interact with it with its actuators (possibly to learn more - that would then be experimenting in stead of plain observing - a next step in intelligence). This set of rules would be its a priori knowledge, what math is to us. (See also miscellaneous question 3 above). DirkvdM 07:21, 10 January 2006 (UTC)
Of course, if it convinced you, that would count as passing a simple version of the Turing test.--Fangz 20:45, 12 January 2006 (UTC)
Ah, but a simple version of the Turing test would prove nothing at all. The Turing test would have to be very extensive to approach a proof (it still won't be one). You have to keep on trying to trick the machine into making a mistake. Suppose all experts of the world (in all fields, including, say stamp collecting) would come together and put all their knowledge in the machine. The biggest hurdle would then be linguistic - getting it to present that knowledge in a way that sounds convincing. But assume that hurdle is taken. The biggest problem would then be that the machine would know more than a person ever could. But ignoring that, these experts can then keep on feedding the machine with knowledge (as it appears in, say, newspapers) and the machine would then not need to have any capacity to learn and still pass the test. Unless the Turing test provides for that (I don't know if it does, really); isolate the machine, let it read something and then let it interpret it to see if it can integrate it in the knowledge it already has. Sounds like a good test. DirkvdM 10:13, 13 January 2006 (UTC)

DVD Format

Can you please explain what are the Pros, Cons and differences between DVD+RW and DVD-RW

DVD+RW supports "random" write access, which means you can add and remove files without erasing the whole disk and starting over. You can treat a DVD+RW almost like a removable hard disk. DVD-RW is more like CD-RW. If you want to change something, you have to wipe the whole disk clean and start over. The only disadvantage to DVD+RW I can think of is it might be more expensive. —Keenan Pepper 18:03, 9 January 2006 (UTC)
One more question, then! My computer can do DVD +/- R and RW. Of these, which would I use for fastest data backup? Most reliable? --jpgordon∇∆∇∆ 20:51, 9 January 2006 (UTC)
Speed should be much the same. I backup to DVD-R, as the media is cheap (cheap media means you can make lots of backups without worrying about the cost) and I've never had a backup be unreadable later. In contrast I have a DVD+RW dvd-recorder (you know, the things that replaced VCRs) and I'have had several (good quality) disks show up with errors, even after one recording and very careful treatment. I don't see a reason to backup to rewritable media of either variety. -- Finlay McWalter | Talk 22:38, 9 January 2006 (UTC)
I'll write the above statement to the article. roscoe_x 15:56, 11 January 2006 (UTC)

Defnition of epoch, era and eon

What would be the exact defnitions of 'epoch', 'era' and 'eon'; with refrence to the Geological Time Scale?

Reading the Geologic time scale article should give you enough insight to come up with some good definitions. hydnjo talk 20:17, 9 January 2006 (UTC)

how have modern wars helped with the advancement of medicine and surgery?

Would you like to tell us why you are asking? The reason is that this looks very like a Homework Question. Notinasnaid 18:01, 9 January 2006 (UTC)
And a very good homework question indeed. And we're very happy to help with homework, or we wouldn't be here. War and surgery have always been closely (and sometimes too facilely) linked, though the topic wasn't closely examined as part of the "history of medicine" until fairly recently. Wwars have both helped and impeded the progress of medicine (e,g, by diversion of resources from the civilian population, by encouraging unethical experimentation, etc.) but you ask about "help" only...

Some random associations:

And so on ans so on and so onl Anyway this may give you some things to think about, others may add more. (improvements, or wars, many of each are missing) - Nunh-huh 08:11, 12 January 2006 (UTC)

Gives doctors lots of practice and chances to try new techniques. GangofOne 06:40, 12 January 2006 (UTC)
War provides us with many solutions for the problems of humanity. GangofOne 16:40, 12 January 2006 (UTC)

quantum mechanics

is Quantum theory irrational? --Cosmic girl 18:10, 9 January 2006 (UTC)

Well, it's definitely counterintuitive, but it has to be to explain the counterintuitive results of actual experiments, at which it's startlingly accurate. I wouldn't say it's "irrational"... —Keenan Pepper 18:49, 9 January 2006 (UTC)
Ditto. Let me give you a sense of the excitement that was expressed by J.H. Van Vleck way back in August 7, 1925 in his "Quantum Principles and Line Spectra" -- ...the quantum theory is so alive that it develops and changes almost overnight.. In this publication, the first 14 pages is dedicated to how the postulates of quantum mechanics fall out naturally from the shortcomings of classical mechanics in describing line spectra. Hm... --HappyCamper 20:18, 9 January 2006 (UTC)

I agree with Keenan Pepper. It is highly rational and logical, but counterintuitive and bizarre as well. — Knowledge Seeker 20:30, 9 January 2006 (UTC)

thanx :D...but still, I don't see how something bizarre and counterintuitive can be logical and rational, but I might have missunderstoond u anyway. --Cosmic girl 21:02, 9 January 2006 (UTC)

May seem irrational now, but you have to realise back then, irrational numbers were the one of the most counter-intuitive things to the ancient Greeks (during the Pythagorean era). Elle vécu heureuse (Be eudaimonic!) 22:47, 9 January 2006 (UTC)

Of course something counterintuitive can be rational! Because intuition is not inherently rational. Intuition is experience. When something is in line with our previous experiences then it is intuitive to us. Intuition is a short-cut we take to avoid having to rationalize something, if something seems to "make sense" we accept it and don't bother figuring out why it makes sense. This works quite well most of the time, but once you start considering things which are abstract or very far from our everyday experiences, then intuition becomes increasingly useless. Some simple mathematical examples are the Birthday paradox, the Monty Hall problem and Gabriel's Horn. --BluePlatypus 23:26, 9 January 2006 (UTC)

Continuing along the lines of 'miscellaneous question 3' and 'Thinking pc' above (I've put myself in that mindset, so now I interpret everything in those terms :) ). Quantum theory follows rationality to its logical conclusions. We are born with a priori knowledge, which we use to understand the word around us. All animals and other forms of intelligence have this. We have however formalised those rules (at least we try to). That's called mathematics. Next we started to strictly apply those rules and we came up with all sorts of things that our non-formal minds could no longer follow. You could say we have harnessed our intuition to the point that it's no longer intuitive to us. Then again, the notion of gravity was rather counterintuitive when Newton came up with it (something that excerts a force without touching!?), but we're completely used to it now. So maybe one day everyone will take quantummechanics for granted? Which is not to say we'll fully understand it. After all, do we really understand gravity? We merely accept its existence. DirkvdM 08:07, 10 January 2006 (UTC)

Mutating

Is it possible to use radioactive materials to mutate a human or any other creature in a way that will cause noticeable exterior physical changes while being exposed to the radiation in a gradual way as to keep the person or creature from developing cancer?

Yes and no. Radiation is used to create new varieties of orchids and other plants (I think you can just microwave the the seeds, viruses can also cause mutations). The mutations are completely random however. They usually kill the seed or create useless, uninteresting, or grotesque traits. Sometimes however they can result in a new splash of color on the flowers or new variegations.
This is not an appropriate way to create novel new types of animals for a whole host of biological and ethical reasons which I am not qualified to comment on. Suffice it to say that it would not work. Jasongetsdown 19:28, 9 January 2006 (UTC)

From the desk of the guy who asked the question: well, is it possible to do it on single-celled organisms in order to somehow affect the result of the organisms evolution process?

Look up Mutation Breeding
This has been generally confined to plants since there is a massive number of deaths involved. The irony is that almost all food crops have come from this, and that Genetic Engineering was supposed to be a gentler way of improving crops. --Zeizmic 21:26, 9 January 2006 (UTC)
No. And only no. What happens when you use radiation to cause a mutation? Answer: The radiation hits the DNA molecule, possibly forming a radical, and/or destroying a bond or ionizing it. The radical or ion will then react with whatever happens to be close by. Basically the DNA gets screwed up. Radiation is by its nature random and rather uncontrollable. And the DNA damage it causes is random and uncontrollable. So there is no way at all you can use radiation to cause living mutant cells without causing a lot more dead cells and cancer cells. As Zeizmic says, there's a lot of deaths involved for every surviving mutation. --BluePlatypus 23:11, 9 January 2006 (UTC)
It may be possible to aim radiation at a particular gene instead of the entire DNA of an organism, thus increasing the chance of affecting that gene only. However, I suspect that more precise forms of genetic engineering will make such an approach seem rather inefficient. StuRat 01:05, 10 January 2006 (UTC)
Nonsense. First: cannot aim radiation that precisely. Aiming it at a tumor is something completely different than aiming it at a MOLECULE. Do you realize how many orders of magnitude size difference there is? And even if you could aim it, it's a moving target. And even if you hit it in the right place, the effect of the radiation is still unpredictable. --BluePlatypus 19:39, 10 January 2006 (UTC)
You can't aim with radiation, all mutagenesis techniqes are random. If you want to effect a specific gene you can use site-directed mutagenesis or an expession knock-down technique like RNAi.--nixie 01:14, 10 January 2006 (UTC)
Sure you can aim radiation, there are even cancer tratements that aim it at a specific tumor. Are you saying you can't aim it precisely enough to hit a portion of a strand of DNA, instead of the entire length of the strand ? StuRat 01:39, 10 January 2006 (UTC)
Yes. But since you mention it chemotherapy is not especially specific either, it basically just targets quickly dividing cells, hence the effect on the immune and reproductive systems.--nixie 01:52, 10 January 2006 (UTC)
I don't understand your use of the word "either". Radiation therapy IS specifically aimed at the tumor, with, for example, rods of radioactive material contained in lead tubes, which will aim radiation out the end, much like a gun. Many such tubes allow radiation to be concentrated direcly on a tumor. StuRat 03:54, 10 January 2006 (UTC)
Even targeting a specific set of cells, a radiation therapy like brachytherapy doens't work by causing a specific type of damage to certain cells - it just destroys any DNA by creating so many errors during DNA replication that the cells can't successfully divide (cancer cells divide frequently so they are affected). It will also damage other cells. --nixie 04:24, 10 January 2006 (UTC)
To summarise the above: you need to hit just the right spot to avoid getting something that has no chance of surviving (or even germinating). So if you use blunt unaimed radiation only one in a million (or what?) will survive (and even then there's little chance that that is something you would want). Right? And if so, what is that 'right spot'?
I'm really intrigued by the idea that most food crops have been altered this way, as Zeizmic says. Considering the dispute, I would like a confirmation of that (or a negation, of course). DirkvdM 08:41, 10 January 2006 (UTC)
Most food crops have been altered by selectively choosing naturally occuring mutations, at least some of which are the result of exposure to naturally occuring radiation; it is not true that most food crops have been developed by intentional irradiation by humans. Rmhermen 14:12, 10 January 2006 (UTC)
Many contempoary cultivars of all major food crops (like the cereals) have been produced from radiation or EMS mutagenesis. It's a fast way to produce new tratis which can then be bred into plants by backcrossing.--nixie 05:19, 11 January 2006 (UTC)

omniversal travel

Is it possible to construct a device capable of sending someone to any one of the infinite alternate realities or universes? I also have a possible explanation as to the different variations and types of realities and universes: I believe that there are several different "Prime" universes. We live in the Earth Prime universe, or, the universe that all the different alternate realities are based off. All the litirature, stories, history, video game storylines, movies, and TV shows also have a Prime universe that that goes along with each individual series. History willl have several variations, like, George Washington doing a direct attack on the british instead of sneaking up on them during that fateful night. And your favorite characters from games and movies have their own Prime universes with their own infinite number of alternate realities. They all combine into one HUGE and always expanding omniverse. Anyway, you probably get my point. So, could it be possible to make such a device? (p.s. sorry about the long-winded theory. I tend to ramble on sometimes. I also got swept up by the concept and how exciting it would be if my theory proves true.)68.116.175.201 23:57, 9 January 2006 (UTC)

The existence of alternate realities or parallel universes is only theoretical at this point. I don't believe there is any theoretical framework for the nature of these universes or how they might be associated with ours, so the possibility of travel between them would be completely unknown for now at least. Your best bet is to enjoy some good science fiction on the matter: the Sliders television series, Asimov's The Gods Themselves, and several Star Trek: The Next Generation episodes (as well as from the others series) come to mind; time travel stories also deal with this in a sense. — Knowledge Seeker 20:26, 9 January 2006 (UTC)
Maybe? It's hard to guess how a universe you've made up would work. Maybe it would be possible to move from one bit of reality to another, perhaps taking advantage of whatever it is that connects them and brings them into being in the first place, but maybe no travel or transference would be possible. If somebody in this world were made into a character on a TV show, would they be transported there, or would there be a copy living in that world? How would you deal with all the glaring discontinuities in most TV shows? --Black Carrot 20:30, 9 January 2006 (UTC)

If someone in this world were to be 100% emulated in a TV show, then there would be a copy. As I said earlier about the universes and variations, the TV show would have it's own universe, and have infinite variations. you could have a variation of our universe where YOU (yes, you, Black Carrot) could be of the opposite gender*. As for the discontinuities, there are things in tv shows that are unexplained,and that is where Fanfictions or destiny come in. if there is a unique fanfiction about a book or game, it causes the events of the fanfic to be a real event in that universes Prime. If there are multiple fanfics of the same event in different retellings, they mesh into one rettelling of the event and become true in the Prime of that universe, while variation realities select one of thoes fanfics to be real. if no fanfics are made to explain plotholes, a random explanation happens in the Prime of that universe. The discontinuity could be explained by a fanfic about a change in personality of the character, amnesia, or the characters decision to do something that, ultimately, leads to the lack of continuity. Also, two more things:

  1. 1: Whatever happens in the Prime universe effects the variations that come after it. Changes in a variation only effects the variations that come after it. But in no way do the variations effect their Prime universe, or any others, for that matter. Cross-overs in Fanfics create a variation that is normal except for the cross-over occuring, making it a "Crossed Universe", or a new universe that is one variation of 2 realities.
  2. 2:(*) If this offends anybody, I apologize, and I am not trying to offend anybody in any way.

p.s. I feel like I've found a place where I can share my theories with people without being told to be quiet about "illogical nonsense". :D68.116.175.201 23:57, 9 January 2006 (UTC)

Many people believe that the universe/omniverse/pickyourfavoriteterm is laid out this way, but as a thinking point for your stated view: why is this universe Prime? What distinguishes it from any number of parallel universes, save that you are aware of this one (and consider that "you" are likely singularly aware of a similarly large number of parallel universes within their respective contexts)?

Well, I was trying not to make my posts so long, and thats why I didn't talk about that in my last post. You see, I often think about whether or not were in a fictional world that originated in some book somebody wrote or a lame TV show. For all we know, we could be in the worst sitcom ever made and not know it, But I have proof we're in the Prime Universe. Each variation is caused by the creation of literature that would describe how the world would be if something that happened had occured differently, or never occured at all. If we weren't the prime universe, then there would only be EXTREMELY small changes in between universes. The thing about Variation Universes(VU) is that if the universe is created by a story that tells only about a certain event, then that certain event is the one most important thing in that universes history, while everything else ends up being misinterpreted in general. The Prime Universe was started at random by I-dont-know-what and has no single event being the most important, and all the events that happen in this universe either get lost in the shadow of history or become warped, misread, misinterpreted, and mistranslated over time*. While VU's are created starting with that event, with no history as to what happened before the event took place. (*by this I mean like 200-1500 years)68.116.175.201 23:57, 9 January 2006 (UTC)

Could you sign your work with four tildes(~)? 70.243.46.200 23:50, 9 January 2006 (UTC)

Okay. :)68.116.175.201 23:57, 9 January 2006 (UTC)

Honestly, the fascinating nature of interdimensional travel notwithstanding, discussion of how fanfic creates new universes is not appropriate here. Bethefawn 02:05, 10 January 2006 (UTC)

So long as you can avoid sharing your personal opinions in a way that other people will interpret as original research, which is a huge temptation for many of us here, and instead quote other people as factual presentations of what they have to say on the topic, which may be identical to what you believe, you may find value in contributing to articles on Wiki such as Time travel in fiction. User:AlMac| 07:15, 10 January 2006 (UTC)

Is interferon still active after freezing?

Is interferon still active after freezing?

According to Medline, interferon should refrigerated but *not* frozen. However, this is not medical advice -- if you have a medical question regarding medication, it should be directed to a doctor or pharmacist. This response is not a substitute for medical advice. Adrian Lamo 23:24, 9 January 2006 (UTC)

Interferon is a protein hormone. Freezing sometimes changes the tertiary protein structure, and can reduce ability to bind to receptors. The amount of change depends on lots of factors, but is hard to predict without actual experiments on the specific protein in question. It is unlikely to lose all potency with a single episode of freezer temperature or outdoor winter freezing, and does not become "toxic" or harmful, it just has a reduced potency. The degree of degradation (percent of remaining activity) is difficult to predict and might range from as little as 5% reduction of potency to 90%. Sorry, can't be more precise. alteripse 23:36, 9 January 2006 (UTC)

physics flywheels

I am needing equations and basic information for angle of a flywheel and its varying pulling force which is created by rpms. What weight will the rpms allow the flywheel to pull when its speed increases and decreases? How much should the flywheel weigh? Will the flywheel be at 60, 45, or 30 degrees? This is for an at home project that i hope to take with me to class this fall 2006.

Thank you,

gsm fa smith

Well, I for one don't understand the question, and I think I took this stuff. Use the Magic Answer Box to the left, and try to refine the question. --65.92.79.213 23:09, 9 January 2006 (UTC)
Well, you could start checking at flywheel, but the question itself makes me think the user is in fact asking about gyroscopes. ☢ Ҡieff 23:51, 9 January 2006 (UTC)

Note that it isn't the weight, but rather the moment of inertia of a flywheel which determines how much energy it has for a given rotational speed. A hoop shape will have a much greater moment of inertia than a disc of the same weight and radius. StuRat 00:56, 10 January 2006 (UTC)

Question about the Common cold

Do the antibodies developed during a bout with the Common cold protect one from contracting that particular viral strain again? Specifically, if say within one household, the virus spreads from one to another to another... do the early victims have any immunity to reinfection from the later victims? --hydnjo talk 22:01, 9 January 2006 (UTC)

Sure, as with any systemic infection, either your immune system develops sufficient resistance to it, and you evict it (leaving you with a strong defense against that same strain) or your immune system fails to, and you are overrun and killed by it (that doesn't apply to weird things that hide in out-of-the-way places, like malaria). Infections don't leave of their own accord :) As to reinfection, you're obviously not immune from wholely different strains, but mostly immune to the close relatives of the one you just beat. So if you have two colds in close succession, that's two distinct organisms attacking, not a reinfection by largely the same bug. -- Finlay McWalter | Talk 22:31, 9 January 2006 (UTC)

Distribution of species

Describe, using examples, how abiotic factors of the environment affect the distribution of species. Thank you — Preceding unsigned comment added by 63.130.186.214 (talkcontribs)

From the top of this page:
  • Do your own homework - if you need help with a specific part or concept of your homework, feel free to ask, but please do not post entire homework questions and expect us to give you the answers. hydnjo talk 22:19, 9 January 2006 (UTC)

Where it's cold, only penguins live. More species are likely to live where it's warmer. That's why California real estate is so expensive. GangofOne 16:56, 12 January 2006 (UTC)

where does wax go after it is burned in a candle?

The same place firewood goes when it is burned. See: candle. You'll note that the wax is the fuel, it is actually what is sustaining the fire, not the wick alone. --Quasipalm 23:47, 9 January 2006 (UTC)
Unlike firewood, which is only partially flamable and leaves behind the ash that doesn't burn, wax is 100% flamable and is all burned up to become gases like water vapor and carbon dioxide. StuRat 00:49, 10 January 2006 (UTC)

This was a big issue way back ] Candles dispose of their 'unburnables' in ultra-fine soot. The fragrant candles are especially bad for house soot problems. --Zeizmic 02:17, 10 January 2006 (UTC)

January 10

4 Nipples: An Isolated Incident, Or An Exciting Trend?

At this very moment, I find myself staring, bemused, at an h2g2 article, which describes the author's nipples, in two lucid sentences, as quadruple in number; symmetrical in arrangement, the lower pair being three inches below the upper pair; slightly uneven in size, the lower pair being smaller than the upper pair; and displaying all the characteristic attributes of the traditional human nipple, including sensation. Whether lactation is, or ever could have been, such a characteristic is not discussed. The remainder of the entry, comprising an additional three sentences, contains a description of the measures so far taken to allievate the author's confusion and despair, and an urgent plea for help which can not be lightly ignored by those possessed of even a modicum of compassion and human feeling. In the name of ben4nips, I call for a poll! An immediate and widespread display of generosity for this poor soul, whose only wish is to know whether he is alone in this world, or if there is another who shares his/her fate. If you or anyone you know, here or elsewhere, now or elsewhen, on Misplaced Pages or off, is or knows of someone who owns a perfect set of four or more nipples, respond! Hark to this call! A curious public awaits.

One other thing: try to make sure you can substantiate your story if asked to. We don't want any "I have a cousin who has a friend whose sister's dog heard from their pet psychic that someone they saw on the street had four nipples poking from under her shirt."

The article in question: http://www.bbc.co.uk/dna/h2g2/brunel/A8291702 --Black Carrot 00:40, 10 January 2006 (UTC)

I don't know if the above is even a question, but we have the article Supernumerary nipple. Now a question of my own, is having a third nipple hereditary? Given the instances in my family I'm guessing it is, but our article doesn't say.--Commander Keane 01:45, 10 January 2006 (UTC)

An interesting question. I find it hard to imagine it not being hereditary. To clarify the above: I'd like to know how many people with four (or more) normal nipples there are within reach of this page, or in general, neither of which that page gets into. Another question: What's the most nipples anyone's ever had? --Black Carrot 05:22, 10 January 2006 (UTC)

A third nipple? Given the symmetry of the human body I'd expect an even number. Also, 2% of women have this? Must be very small in most cases then (or haven't I been paying attention?). DirkvdM 08:51, 10 January 2006 (UTC)

I don't think aberations (if that's what you call them) like extra nipples, birthmarks and (say) extra fingers generally come symetrically. And the external links at Supernumerary nipple indicate that most third nipples are not very noticable, some just being a bit of hair, or a small pimple-like formation. When I was younger I thought mine was a chicken pox scar.--Commander Keane 10:43, 10 January 2006 (UTC)
I'm interested to see who here as a 3rd nipple. Do you? --Ali K 14:11, 10 January 2006 (UTC)
For myself, I'd say that extra 'nipples' resembling birthmarks, warts or pimples are of only limited coolness. Like having a sixth finger that's a quarter of an inch long. Now, a second pinky on each hand, that's something. How would the muculature work for that? Imagine that person's forearms. Anyway, I've heard that third 'nipples' are relatively common(meaning you might actually come across a few occasionally), but no word yet on how common people with natural-looking and fully functioning extra pairs of nipples are. --Black Carrot 22:40, 10 January 2006 (UTC)
Are the extra nipples fully functional? Sounds very sexy. User:AlMac| 22:43, 10 January 2006 (UTC)
Male nipples don't have much function anyway. As for girls, apparently they generally aren't functional, but sometimes a breast develops behind them. Black Carrot 22:55, 10 January 2006 (UTC)

I knew a girl that had 6. She only showed us the extra 4, and the top 2 were almost regular but with no areola, and the bottom 2 were pretty small with one of them being almost not noticeable, more like a birthmark. I don't recall if she said they were sensitive or not. The article describes that they can be nearly fully developed, so I would assume that would include innervation. - Taxman 16:23, 11 January 2006 (UTC)

That's one. Out of curiosity:
  • Did they "appear along the two vertical "milk lines" which start in the armpit on each side, run down through the typical nipples and end at the groin"?
  • How far down was each pair?
  • How old was she? If prepubescent, and you've seen her since then, was there any additional development? --Black Carrot 22:11, 11 January 2006 (UTC)
  • She was 20, fairly attractive because I know that was an implied question, and yes they lined up vertically. Each row was about 2-3 inches below the next, I can't remember exactly it was 10 yrs ago. Never saw her again, it was a friend of a friend type thing. It's basically a vestigial mammalian thing, so think how they line up on any other mammal that has them. - Taxman 00:29, 12 January 2006 (UTC)
Anybody else? Black Carrot 01:39, 15 January 2006 (UTC)

Eating faster

Does eating faster make you fatter???

This is a nice link Get the movie Supersize Me, and slow down. --Zeizmic 02:52, 10 January 2006 (UTC)
Possibly. Here are a couple of ways this could happen:
  • If you have a short time to eat, say before you need to leave for work, then eating faster may allow you to take in more calories in the short time period.
  • Eating has a certain amount of tradition and habit to it, so if your brain doesn't feel like you have done the proper eating ritual, it may tell you to go back and do it again. This is one reason why popping pills for all your nutitional needs might not work, either. StuRat 02:59, 10 January 2006 (UTC)

A physiological reason is that incoming food stimulates release of incretins and other hormone signals that begin to signal satiety to the hypothalamus. If you eat fast, you put more food in before your brain decides you aren't so hungry anymore. alteripse 03:33, 10 January 2006 (UTC)

If you watched the UK Sky One Paul McKenna programme yesterday (which you may possibly have done to prompt this question) you'll notice he also discusses this. I've tried it, and eating slower does make you feel more full. Alteripse's explanation is perfect - you could describe there being a lag between you eating, and your stomach telling your brain you're feeling full. Eating more slowly allows time for you to feel full while still eating thus eating less instead of over-eating and then feeling bloated. You can find clips from the "Paul McKenna will make you thin" show at http://www.skyone.co.uk/mckenna -Benbread 20:36, 10 January 2006 (UTC)

No. Check out top competitive eaters, they are not fat at all.  Grue  11:46, 12 January 2006 (UTC)

history of the internet

Maybe try History of the Internet? --AySz88^-^ 03:59, 10 January 2006 (UTC)

Body Heat

How much heat can a body really give off? Why does the room temperature raise when i enter?

According to the average human gives off a minimum of 240 BTU/hour (70 Watts) of heat. So yeah, that's why room temperature rises when you enter (though I'd be surprised if you can sense it except over long periods of time in a small, insulated room). -User:Lommer | 07:11, 10 January 2006 (UTC)
Sorry to reply to myself, but this source estimates that the body can produce up to 2000 BTU/hr for periods of exertion. They also quote 400 BTU/hr as the minimum. -User:Lommer | 07:19, 10 January 2006 (UTC)
Looked up btu. Truns out it's almost equal to 1 kJ.
As for some examples. I was once in a New Zealand tramping hut without a stove, wet and freezing my balls off. After awhile a group of over ten people entered and within 10 minutes I was warm. I was really impressed by the effect. And a Dutch architect has desigend an office building that does not require heating because it makes use of the heat generated by the people and computers inside. I don't know how much each contributed, though. And the same for the Glass Palace, which was a department store with a very advanced (for the time, but still, I believe) climate control that used the warmth of the customers to heat the building. DirkvdM 09:06, 10 January 2006 (UTC)
I once read that a current office building in Kiruna neeeds cooling 90% of the year (!), so that dutch architect probably didn't really do something really rememberable. There are also regular houses built outside of Gothenburg that are heated only by the humans and electrical equipment (no heaters). As office buildings have a lot more computers and other stuff in them than normal houses, I wouldn't think it was that difficult for him... TERdON 02:07, 12 January 2006 (UTC)
Way up in Kiruna, no less! You Scnadinavians really are among the most progressive people I've heard of (both politically and in engineering). If it's that easy, then why do most offices still use heating? Have they been designed so badly? But the first oil crisis was 30 years ago and offices probably have a considerable turnover (or what is tha called? I mean they get torn down and rebuilt). So one would think many would now no longer need heating (most of the year at least). DirkvdM 11:02, 12 January 2006 (UTC)

Firing Distance

Lets say you shoot a standard Revolver with a standard bullet into the air at 45 Degrees, how high would it go, and how far would it go? Have there been any documented cases of people getting killed by bullets that just fell from the sky?

I don't know anything about a bullet's initial velocity or drag coefficient (both of which I would think would depend on which 'standard' bullet you used), but I've heard that it's impossible for a bullet/coin/etc to fall fast enough to penetrate a person's skull. see terminal velocity --Black Carrot 05:31, 10 January 2006 (UTC)
Note, however, that a bullet could still kill by penetrating an eye, the heart, the neck, or soft spots on the skull, like at the template (and growth seams in children). StuRat 03:22, 11 January 2006 (UTC)
  • I can't find it right now but snopes debunked that a bullet coming down after being fired straight up would kill someone (i.e. it won't). Apparently a bullet's terminal velocity is lower than its muzzle velocity by quite a bit. As for the first part of the question, what is a "standard revolver"? There are so many kinds, you would really have to specify the type and ammunition to get a decent answer. Even then, I'd guess an experiment would be the easiest way to predict it with any accuracy. -User:Lommer | 07:04, 10 January 2006 (UTC)
Suppose the bullet lands anywhere (anywhere) on Earth. About 2/3 is water. And on land only a few percent (?) is built up. And even if it falls in a city. Suppose 1 million people on 100 km (roughly Amsterdam). Seen from above, one person takes up maybe 0.1 m. Times 1 million is 0.1 km. That's 1/1000 of the surface. Add to that that (depending on the culture and the time of year) maybe a few percent of people will be outside, and many of those in cars. So even if you fire a gun straight in the air there will be a chance of one in a hundred thousand that someone would be hit. Supposing that this has been done in Amsterdam maybe a few hundred times since the invention of guns (haven't a clue really) and chances are it never happened here. But somewhere on Earth? Most probably.
For example. A great great grandfather of mine once went hunting with bow and arrow (hey ho). He shot at a bird, missed, and waited for the arrow to return. Which he didn't see coming. Guess why.... And now for the romantic conclusion. He was engaged and said to his fiancee that the couldn't make her keep her promise now that he was so deformed (one eye out). But she said she loved him for who he was inside (or something similarly tacky) and still wanted to marry him. Now isn't that sweet? (Also, if she hadn't I wouldn't have been here.) DirkvdM 09:29, 10 January 2006 (UTC)
Firing distance depends mostly on muzzle velocity. Larger rounds can have a much higher muzzle velocity. Smaller rounds cannot. So, wind resistance plays a minor role. The larger the round, the more wind resistance, the higher muzzle velocity you will use to overcome it. I never studied handguns. I studied rifles. The asbolute maximum distance a round may travel is rarely noted. Instead, the maximum distance that a target may be hit is used. For example, the M16 is highly effective at 500m, with a maximum effective range of 1,200m. Assuming that it can travel at least twice the maximum effective range, you are looking at well over 2,000m for a maximum distance. --Kainaw 14:22, 10 January 2006 (UTC)

I entirely doubt that anyone debunked this, because there are verified reports of people being killed in this way by 'celebratory fire'. --Fangz 19:51, 10 January 2006 (UTC)

I got around to looking this up on Cecil Adams's website, and here's what he has to say about death by falling bullet: http://www.straightdope.com/classics/a950414b.html --Black Carrot 22:51, 10 January 2006 (UTC)

Router transmission rate help

I need some help with setting the wireless transmission rate on my Siemens SpeedStream 6520 router. It is set to AUTO by default, but I need to change it to 2 Mbps to get it to work with my Nintendo DS in online play. I've found the option, but changing it seems to have no effect; the setting stays on AUTO. Changing all other settings seems to have a permanent effect though. If you want, you can watch this video of my attempt at changing the settings (you'll need the Microsoft MPEG codec, which comes with Windows XP). If anyone else has this same router, help would be greatly appreciated. -- Daverocks 05:10, 10 January 2006 (UTC)

I don't have that router, but on my D-link you need to reboot the router for some settings to take effect. I watched your video, after clicking "Finished" click on "Reboot" (you will loose you internet connection while it reboots), and let us know if that works.--Commander Keane 07:32, 10 January 2006 (UTC)
Rebooting does help to bring other settings into effect, but seemingly not the data transfer rate. I've tried it a few times, both by resetting the switch physically and clicking "Reboot" on the interface. Thanks for replying though. -- Daverocks 09:04, 10 January 2006 (UTC)
Can you get it to use any wireless transmission rate other than 2 Mbps? Also, I'm surprised that the DS needs the router settings to be changed (I thought they had some crafty people at Nintendo). Have you tried the DS while just using the Auto setting?--Commander Keane 10:20, 10 January 2006 (UTC)
Nope, can't change it to anything else other than auto. And if my DS worked properly at the AUTO setting, I would never have touched my router settings. However, it commonly freezes at the start of a race (it's Mario Kart DS), and I get an error code 94030. I found a huge thread here with people having the same problem, and they mostly report that changing their transmission rate solves their problem. -- Daverocks 06:51, 11 January 2006 (UTC)
Sorry to insult you about the whole "crafty people at Nintendo", I should have googled to see that this was a common problem with the DS. A google search of the Siemens SpeedStream 6520 indicates that the firmware is crap. Are you running the most up-to-date firmware? --Commander Keane 07:56, 11 January 2006 (UTC)
I agree with you on the quality of the firmware. I'm probably not running the most up-to-date firmware, but I wouldn't know where to find newer. A google search doesn't help me much. Maybe you could help me find a link to updated firmware? :) -- Daverocks 07:14, 12 January 2006 (UTC)
Wait, I don't want to have sounded stupid in what I just said. Is it actually possible to download updated firmware from the Internet and install it on the router? (I apologise if this question sounds stupid.) -- Daverocks 07:17, 12 January 2006 (UTC)

I never consider any question to be be stupid and you are right, you can simply download firmware from the internet. Your router will actually download it for you. I'll paraphrase the instructions found in the instruction manual

  • Click the Update Firmware button from your "Gateway Health" window
  • Select Remote to get the router to check for the software online

WARNING: Do not interrupt the Gateway during the firmware upgrade session (it's not kidding, if you unplug half way through the upgrade the router will need to be returned to the factory, the reset button won't work either). Let me know how you get on. --Commander Keane 18:35, 12 January 2006 (UTC)

Hmm, I don't seem to have the "Update Firmware" button under "Gateway Health", even while logged in as admin. If you look at this image I made of my interface versus the manual's interface, it is clear that I don't have the option. Maybe I need to update my firmware so I can get the "Update Firmware" button ;) -- Daverocks 10:50, 13 January 2006 (UTC)
I give up. Give Siemens tech support a phone call (or maybe Bigpond), because this is one hell of a Bowser sized problem.--Commander Keane 14:03, 13 January 2006 (UTC)
Heh, maybe I will. Thanks a bunch for your help, anyway. -- Daverocks 01:33, 14 January 2006 (UTC)

Periods during pregnancy

Is it possible for a woman to have periods during pregnancy, and if so, will the cycle (during pregnancy) differ from the normal menstrual cycle (that is, when the woman is not pregnant)? I ask because I've checked the Menstrual cycle and Pregnancy articles, and neither say anything about it. I thank you greatly if you can answer this. --JB Adder | Talk 05:12, 10 January 2006 (UTC)

I wouldn't think so. A period involves flushing out that month's egg and everything that would have supported it through pregnancy so they can be remade for the next month. If somehow something resembling a period did occur, I would think it would remove the embryo/fetus/child as well. And the way I'm used to hearing, the monthly period stopping is one of the traditional signs of pregnancy. --Black Carrot 05:27, 10 January 2006 (UTC)
  • While a pregnant woman doesn't menstruate, bleeding duing the first trimester is relatively common, and could be a sign of a complications like an ectopic pregnancy or a miscarrige.--nixie 05:47, 10 January 2006 (UTC)

Pomegranate

How do you properly describe the distribution of seeds inside a pomegranate? --HappyCamper 05:46, 10 January 2006 (UTC)

Each seed resides within an aril. I've always thought of the arils as "clusters" separated by a white membrane. hydnjo talk 15:52, 10 January 2006 (UTC)

Time and relative demensions in space(TARDIS)?

How would I make one of these?--205.188.117.71 06:04, 10 January 2006 (UTC)

Go to God school ?
If you literally want to make the actual TARDIS, then you are pushing your luck; TARDISes uses highly advanced sciences, which we humans cannot even begin to understand. If, on the other hand, you just want to find out what comprises of a TARDIS, then go to the TARDIS article.
If, on the other hand, you just want to make a model TARDIS, then look for the Doctor Who Technical Guide in your local bookshop or second-hand store, or you can ask me to send you the scans of the actual pages which contain how to make a model TARDIS. --JB Adder | Talk 07:42, 10 January 2006 (UTC)
Does the bookshop have to be local? What if that doesn't have it, is he allowed to go to anbother one? :) DirkvdM 09:32, 10 January 2006 (UTC)
He can go to any bookshop in any time or space, but first he'd have to make a TARDIS. DJ Clayworth 18:17, 10 January 2006 (UTC)
Become a Time Lord. --Canley 13:25, 10 January 2006 (UTC)

The Brigadier: "Damn it, can't we just once, just one damn time, be invaded by hostile aliens who aren't immune to bullets ?" StuRat 07:25, 11 January 2006 (UTC)

Flight at low altitude

Is flight at low altitudes possible? If so why aeroplanes fly at such high altitudes? If not why is it not possible?

Of course it's possible. However, if I remember correctly, it's not efficient to fly at low altitudes. Dysprosia 08:08, 10 January 2006 (UTC)
  • It also helps commercial airplanes avoid high buildings, paragliders, and all sorts of other things you have at lower altitudes. - Mgm| 09:30, 10 January 2006 (UTC)
At high altitudes planes may catch a jetstream that goes their way. At very low altitude, however, a plane could use the aircushion that form between it and the ground for lift (saving energy again). This would of course be a very low altitude, like 2 m or something. Alas I forgot what this is called. And the surface would have to be very smooth, like water. In that case, it could even dip its wings in the water and become a hydrofoil. In which case it would no longer be called an airplane, though. DirkvdM 09:39, 10 January 2006 (UTC)
That is called ground effect and it occurs when an aircraft is within 1/2 its wingspan from the ground. Not a good thing to be doing a 500 mph. Turbine engines are much more efficient at high altitude which is why they fly as high as they do, also at normal cruise altitudes planes are able to avoid most bad weather.--Puck 09:46, 10 January 2006 (UTC)
To illustrate the effect of a jetstream as a way for airlines to save time and fuel an example. Flying across Australia from Sydney to Perth takes 4h 45m while the return trip is 40 minutes (14%) shorter, at 4h 05m. (Source: & )--Commander Keane 10:31, 10 January 2006 (UTC)
If you want to see proof, enjoy:
http://www.wimp.com/under/
http://www.wimp.com/altitudefour/
http://www.wimp.com/altitudethree/ --Black Carrot 22:07, 10 January 2006 (UTC)
  • There are at least five reasons why airliners fly at high altitudes, of which three are noted above.
    • It is more efficient: this is because there is less air at high altitudes and therefore less fuel must be burned to overcome air resistance.
    • It is impossible to crash into a mountain, even if you make a navigational error, if you are flying higher than any mountains on your route.
    • On certain routes the plane may be able to take advantage of a jet stream.
    • In addition, the flight will generally be above the weather, since most weather systems are confined to the troposphere. While turbulence is still possible in the stratosphere and thunderstorms or hurricanes may extend that high, in general one expects a smooth ride.
    • Finally, high-altitude flight is significantly safer if something goes wrong, because it takes time for the plane to descend. For example, if an airliner runs out of fuel at cruising altitude, it can still reach an airport 50 miles away or even farther; this gliding ability is why this incident ended happily. Or in other situations, such as these two, the pilot has time to identify how the crisis impairs the functioning of the plane and to deal with it at least partially. Of course disasters can happen at high altitude as well, and the need for cabin pressurization introduces its own risks (as in the last incident I mentioned), but they are not as great as the risks of flying near the ground. Most accidents that do happen happen at one or the other end of the flight, when the altitude is lowest, and a big reason is the absence of time to react to problems.
--Anonymous, 23:20 UTC, January 10, 2006
Also, there is a need for "stacking". Since many airplanes must cross each other's paths (as viewed from the top) it is necessary to have them at different heights so they don't usually crash into each other until they are paid off. Typically they are spaced out 1000 ft apart. So, just 5 such stackings result in a spread of almost a mile. "Puddle jumpers" (short-run flights) are usually at the lower altitudes with long-range flights at the top. Planes circle up to and down from altitude near their departure and arrival airports. StuRat 03:15, 11 January 2006 (UTC)


As an example of a airliner flight conducted at low altitude, with disasterous consequences, see Air New Zealand Flight 901. --Robert Merkel 00:32, 12 January 2006 (UTC)
Technically, hovercrafts can be viewed as flying too. At a few decimeters' altitude. TERdON 02:14, 12 January 2006 (UTC)
Ok let me restate my question. I wanted to ask why weren't we able to build a flying machine that would fly at low altitudes like birds??
Sign with four tildes(~), please. A few reasons. Many are listed above. Another is that, to hold people, a plane must be at least a certain size, which makes it significantly less maneuverable than a bird, which is dangerous down where there are trees, telephone lines, people, and lots of other birds. If you don't require that it hold people, there are plenty of planes (everything from folded paper to full-on RC http://www.wimp.com/remoteairplane/) that are the size of birds and that fly at much the same altitude. Black Carrot 04:58, 12 January 2006 (UTC)
Also, fighter jets occasionally fly at very low altitude - to avoid radar, for instance. They are manoeuvrable and small enough to be able to avoid obstacles more easily than a full-sized passenger airliner, but low-level flying is still extremely hazardous, because human reactions just aren't always fast enough to avoid obstacles at several hundred kilometers an hour. Also, if you're flying over populated areas, the noise will be an issue, as airplanes are (still) very noisy beasts. So, to answer your questions: we can build planes to fly at low altitude, but it's rarely practical / useful to do so.
And since you talk of "flying machines", I'm amazed no-one has mentioned helicopters - they often fly at altitudes comparable to birds. Since they can hover (and fly more slowly than airplanes), they are easier to fly close to the ground. — QuantumEleven | (talk) 09:25, 13 January 2006 (UTC)

Bio Medical Engineering

I'm doing Electronics engg. Is it possible for me to continue my higher studies in bio-medical engg? How many years of study is it? Wat are the universities in the U.S.A. and U.K. which offer this course? Wat are the job opportunities for this course?

Re-edited by JB Adder to remove preformatting. --JB Adder | Talk 09:00, 10 January 2006 (UTC)
You're asking the wrong people here. Ask your course co-ordinator/college professor about this, because we are in no place to answer such a question. --JB Adder | Talk 09:04, 10 January 2006 (UTC)
There are certainly opportunities to continue your studies into biomedical engineering - I'm biased, because it's what my degree is in, but there's plenty of job opportunities. You For a list of which universities offer biomedical engineering in the UK, try www.ucas.com. Proto t c 11:32, 10 January 2006 (UTC)

My Dad had a job at the "entry level" in this field (before he retired), he did maintenance and repair on medical equipment at a hospital. This only required an Associates Degree (2 yrs) from a community college. Designing said equipment would be the high end in this field. StuRat 03:04, 11 January 2006 (UTC)

powder flow properties range

pharmaceutics : tell me a powder flow properties range

AC source frequency

Household appliances like fans operate at frequences around 60HZ...wheras aeroplanes work at 6000HZ...give reasons

Hey Sturat, make us up a good 'Homework' template. --Zeizmic 13:21, 10 January 2006 (UTC)
Sorry, but "I's don't knows nuttin' 'bout birthin' no templates". I also rather enjoy the personalized abuse we aim at those asking stock homework questions. StuRat 03:00, 11 January 2006 (UTC)
Regardless, check our article on transformers. The answer is there, but this case is noted precisely at the high frequency operation section. But please, read the whole thing to properly understand the reasons. ☢ Ҡieff 14:56, 10 January 2006 (UTC)
No they don't, they operate at 50Hz! :) DirkvdM 09:36, 11 January 2006 (UTC)

Film deaths?

When you see someone die in a film usually through being shot or stabbed through the torso they begin to bleed through the mouth or nose, is this realistic? and why does it happen? (7121989 13:37, 10 January 2006 (UTC))

Puncture the lung and it will fill with blood. When you breath out, blood comes out. --Kainaw 14:10, 10 January 2006 (UTC)

It happens more often in films than in real life. Think of it as the cinematographic equivalent of replacing the eyes with X's in a cartoon. alteripse 17:22, 10 January 2006 (UTC)

Or crashing cars exploding. Hardly ever happens in real life. DirkvdM 09:37, 11 January 2006 (UTC)
Heh. On The Simpsons, everything that crashes explodes. Including The Flying Nun. User:Zoe| 00:50, 13 January 2006 (UTC)

Hydrogen Production

My father-in-law has an idea to produce hydrogen by putting high voltage into a tank of water and bottling up the hydrogen as it comes out of the water. I've tried to argue that it will not work, but he doesn't believe me. Anyone have simple arguments against this? I'd like to get him to stop before he electrocutes himself. --Kainaw 14:09, 10 January 2006 (UTC)

this is possible check electrolysis, the electricity splits water into its ions as they then lose or gain electrons in redox or oxidisation reactions. (7121989 14:20, 10 January 2006 (UTC))
High voltage produces sparks. Hydrogen is very flammable. If it works, he'll blow his tank up, and possibly himself (show him a picture of the Hindenburg). And if it doesn't work, then he won't have any hydrogen. So it's either potentially fatal, or pointless. Point him in the direction of hydrogen cells, which use electrolysis in a safer manner. Proto t c 14:24, 10 January 2006 (UTC)
If you want to experiment with hydrogen, then do this experiment in a small bottle and use a 9V battery so you dont have the risk of a explosion or a elecro-shock. helohe (talk) 15:39, 10 January 2006 (UTC)
Basicaly something like this will work:

If the above doesn't scare him, then know that it is possible to walk into a hydrogen burn without seeing it. This happens at refineries all the time. --Zeizmic 15:56, 10 January 2006 (UTC)

Anyway, electrolysis like this is perfectly possible and practical; people do it all the time. (It's a standard demo in high-school chemistry classes, for example.) You don't actually need high voltages, either. (The amount of hydrogen you get is proportional to the current, so you're better off with lower voltages and higher currents.) But, you won't solve the energy crisis this way, because the energy you get by burning the hydrogen you generate won't be any greater than the energy you spent splitting it off in the first place. Steve Summit (talk) 18:29, 10 January 2006 (UTC)

We need to discover that enzyme that apparently generates hydrogen and oxygen from water in photosynthesis. I asked my biology teacher what it was, and I'm surprised we haven't discovered it yet. Then we would just need it to work in-vitro, which we can just provide heat to drive the energy for. Elle vécu heureuse (Be eudaimonic!) 22:38, 10 January 2006 (UTC)

Remember there is a difference between protons and hydrogen gas. However, in some photosynthetic organisms (algae) there is a hydrogenase enzyme that will give the proton an electron to release hydrogen gas. This will only work under atypical conditions but it is possible to build a bioreactor. See the following reference for more details Melis, A.; Zhang, L.; Forestier, M.; Ghirardi, M.; and Seibert, M.; Sustained photobiological hydrogen gas production upon reversible inactivation of oxygen evolution in the green alga Chlamydomonas reinhardtii; Plant Physiology 122; pages 127-135. A bacteria Pyrococcus furiosus also has hydrogenases. i'm sure there are many more examples in bacteria and algae. David D. (Talk) 22:54, 10 January 2006 (UTC)
Don't know what source he was thinking of (or purpose, for that matter), but I suppose you need DC for this, not AC....
I tried this as a kid; I split a double wire at both ends, exposed the cores, made the wires at one end of unequal length, put that end in a test tube and stuck the wires at the other end in a wall outlet. At that moment I saw a big blue 'flash' (don't know how to describe it, but it was all-encompassing, not a streak of lightning or something) which blinded me for a few seconds. At the same time I heard shouts from all over the house. I had blown a central fuse or something. I've done some weird stuff in my youth (and the rest of my life for that matter) but this gave me the biggest fright of all. I've had a healthy respect for electricity since. DirkvdM 09:52, 11 January 2006 (UTC)

Which drug comes closest to being a healthy replacement for sleep?

Which drug is the safest or most acceptable "replacement" for sleep in the long term?

If you go over to the Magic Answer Box on the left and type in 'sleep', you get a really good article (I just read it!). There is no substitute for sleep. If you're a fighter pilot and your life depends on staying awake a bit longer, then there are fancy stimulants, but you will pay for it. --Zeizmic 18:05, 10 January 2006 (UTC)
Please do read the Sleep article and you will gain some insight and understanding. hydnjo talk 20:23, 10 January 2006 (UTC)
Actually, modafinil is a "mild" stimulant which seems to exact a fairly light price for the wakefulness it gives in return. Military test subjects have used it to stay fully awake (e.g., no loss of coordination or cognitive abiities) for 72 hours, then sleeping for 8, over several months at a time with no apparent ill effects. It will, however, give your urine the sulphurous odor of rotten eggs. —James S. 07:20, 11 January 2006 (UTC)

Death of course, is an eternal form of sleep. . Elle vécu heureuse (Be eudaimonic!) 00:41, 11 January 2006 (UTC)

Hey guys, (s)he's asking about sleeping drugs, not stimulants!.
There can be several health risks. Firstly of course the risks of drug use in general, such as potentially lethal doses, dependence (having more trouble to get to sleep without it) and tolerance (needing ever higher dosages). Barbiturates are among the oldest 'modern western' sleeping drugs and among the nastiest drugs in general when it comes to kicking the habit. Worse than heroin I've heard. People have committted suicide during abstinence.
But I suppose you mean 'healthy sleep'. Since little is known about sleep little can be said about that. I was a very bad sleeper as a kid until I discovered marijuana. Just a small dose works miracles. However, as many have observed, it deprives you of your dreams, which doesn't sound too healthy (or, alternatively, you can't remember them in the morning). But I've used it for about 25 years (on a daily basis, except when travelling) and I'm still pretty sane (ehm....). Something that is often conveniently forgotten by anti-drug fanatics is that the dosage is all-important. Same with legal medical drugs and poisons (it's not the stuff that's poisonous but the amount or the concentration). Except marijuana is rather unique in that it has no lethal dosage and i ngeneral it's one of the safest drugs around. I'd say, try to find a drug-free way to get to sleep (meditation didn't work for me, but maybe it will for you) and if you must use a drug (and it's legally safe enough where yo live) try marijuana.
Having said that, I'm getting off marijuana, alcohol, tobacco and coffee at the same time right now (gradually lowering the dosages). Tobacco is the toughest one to kick, but I'm almost down to zero use now. DirkvdM 10:15, 11 January 2006 (UTC)

Who discovered DNA?

HI I'm doing a project on DNA at secondary school level (year 10) but first of all need to un derstand the basics, in terms of discovery, in a simple way. Who actually discovered DNA in terms of the helix model, because I always get a variety of names. Was it Rosalind Franklin, or James Watson and Francis Crick? I would be at this stage very grateful of any information received! Thanks.

Yeah! Once again I tried the Magic Answer Box and typed in DNA. You should try it, it's really fun! --Zeizmic 18:08, 10 January 2006 (UTC)
Do please read the DNA article as it will help with your understanding of the different helix geometries. A year 10 student should be able to understand most of the article. Come back if there is something in the article that you don't understand. hydnjo talk 20:31, 10 January 2006 (UTC)

"High grade" versus "low grade" energy?

A question for the thermodynamicists out there. I get the impression that it is probably useful to classify various energy sources as being "high grade" versus "low grade" or something in between, depending on how generally useful they are. For example, an energy source that manifests itself as heat with a temperature just a few degrees above ambient is "low grade"; you can use it to warm yourself up, but not much else. On the other hand, electricity is extremely "high grade"; you can do almost anything with it. (Mechanical energy, such as produced by a motor, is somewhere in between.)

Mixed up with my notion of "high grade" is an element of controllability; we seem to place a (to my mind) ridiculously high premium on the easy controllability of energy. For example, in a diesel-electric locomotive, diesel fuel is burned in a diesel engine to produce rotary motion... which turns a generator which generates electricity which is used to run motors to develop rotary motion again. This twice-around-the-barn conversion pathway comes at a pretty steep cost in efficiency, as opposed to having the diesel engines turn the wheels directly, but the compensating advantage is that the electric motors can be very finely and gradually controlled, whereas a pure-diesel locomotive would require some kind of high-power transmission, and those are notoriously difficult to build.

The tradeoffs can also be seen in home heating. If you heat your house with electricity, it's seemingly 100% efficient: any electricity which isn't converted by your electric heater into heat to heat your house with is lost as waste heat which... also heats your house. But of course it's not 100% efficient if you go back and look at the fuel that was (typically) burned in order to generate the electricity in the first place. If you had used the same amount of fuel to heat your house with directly (i.e. by burning it in your own furnace) it would certainly be much cheaper (and probably also more efficient). Heating your house with "high-grade" electric energy is overkill; heating is one of the few things you can usually get away with using the lowest grades of energy for.

Anyway, all of this is by way of prelude to my question, which is: what terms do real thermodynamicists use to talk about these notions which I've informally and unscientifically labeled "low grade", "high grade", and "controllable"?

Steve Summit (talk) 18:13, 10 January 2006 (UTC)

I believe the concept of high grade and low grade can be defined by exergy, which is the maximum amount of work that can be obtained from a system before it reaches equilibrium. Akamad 19:39, 10 January 2006 (UTC)
Which basically is that low-grade energy has a high amount of entropy, and high-grade energy has a low amount of entropy, right? I one time brought the topic to my physical science teacher of why we couldn't just use concentrate the exhaust of the air conditioner to a heating point and use the thermoelectric effect to generate current to help alleviate the apparently expensive energy costs of using energy to ... remove heat energy from the air. He responded by saying that the thermoelectric effect creates "low-grade energy" and suggested using a steam turbine instead, which puzzled me at first, because it looks more inefficient. Elle vécu heureuse (Be eudaimonic!) 22:34, 10 January 2006 (UTC)
See also Gibbs free energy deeptrivia (talk) 05:41, 11 January 2006 (UTC)

I like the term Energy density (a rather undeveloped article). High-grade energy is the same as high-density energy. Low-grade or low-density energy requires a large amount of space, such as wind power, or trying to extract waste heat. --192.75.48.150 12:52, 11 January 2006 (UTC)

Matlab for fringe counting

Can anyone give some idea as to how to count the number of fringes in a photoelastic material on being loaded. The fringe pattern consists of several fringes, of usually distorted elliptical shape, but other patterns may also be seen. So how can I make an algorithm so that even if distortions are present, the counting will be accurate? Note that algorithm should be for matlab only. — Preceding unsigned comment added by NIKHIL SHARMA (talkcontribs)

Have you searched (in a journal database, Compendex is good if you have access to it) for: photoelasticity AND fringe AND algorithm?
Do you have any image processing algorithms yet (eg have you run an edge detection algorithm) or are you starting from scratch?
I'm curiuous, what is this for? Are you a materials science uni student?--Commander Keane 23:30, 10 January 2006 (UTC)
Well commander keane, thanks for answering, but I dont have any access to your mentioned journals. We, i.e. me and my friends are working on a project for : STRESS ANALYSIS USING DIGITAL IMAGE PROCESSING in which we want to use algorithms for fringe counting, which then would be used for further analysis. I and my friends are mechanical engineering students from India. Yes we have used and are familiar with the in-built edge detection methods like LoG, canny, prewitt et al. But still we want some theoritical base as how to count them , the logic behind them, and also how to make up for anomalies in the fringe pattern. And yes, we are starting from scratch. So could anyone mention journals or websites catering to above needs. And note that the explanation should be in regards to matlab and if possible the journals should be free. (well, asking for too much?) — Preceding unsigned comment added by NIKHIL SHARMA (talkcontribs)
NIKHIL SHARMA, please post any additions right here, you don't need to start a new question for every reply. I'm disappointed that you don't have access to Compendex (or maybe Science Direct, that's a good one too) from your library computer system. However, I've had a look at some journals articles but none of them mention the edge counting algorithm. I'll keep on looking but don't keep hopes up. In the mean time, have you considered asking a lecturer in the computer science departement of your university who specialises in computer imaging (or maybe a PhD student)?--Commander Keane 04:38, 12 January 2006 (UTC)

Remote Noise Interferance

I hooked my Wireless Transmitter into my Digital Cable and then I hooked my Wireless Reciever into my DVD Recorder. Now when i press a button on any remote, i hear noise interferance on the TV. Is there anyway to prevent this?

The obvious way to prevent this interference is to not use wireless transmitters and receivers. Most remote controls are infrared, and I don't see how that could produce noise interference, unless your remotes work on a wireless radio system. -- Daverocks 05:52, 14 January 2006 (UTC)

Semantic but valid question on article about Gaia Hypothesis

I realize that I have no scientific standing to ask a question about the article on the Gaia hypothesis, although I took graduate courses in geology in the early 80's, and in early 1979 took one of the good, early courses on "Ecoscience." I simply do not understand the language usage in one very specific case at the end of the article. It seems to me that the discpline of ecoscience of around 1980 had already developed a better and also accepted usage for one specific case which I describe below, in terms of a specific, just barely possible modification of one phrase at the bottom of the article on Gaia:

At the bottom of the article, there is an abbreviated section titled: "Gaia hypothesis in ecology." Here it is stated that "most ecologists agree to assimilate the biosphere to a super ecosystem...." Could this simply be a minor carelessness at the end of a very wonderful article? Let me voice my doubt by asking a question about the use of the phrase "super ecosystem." In what way does the expression "super ecosystem" differ in its meaning from the old "ecosphere" of around 1980? The "super ecosystem" as used describes the Earth at a planetary scale, such as is involved in the simpler description of "ecosphere."

Thank you for looking into this. --Eorth57 21:25, 10 January 2006 (UTC)

I fixed your formatting. Hope you don't mind. —Keenan Pepper 21:32, 10 January 2006 (UTC)
I don't have an answer to your question, but you might also want to post it to the article's talk page. Each article in Misplaced Pages has a talk page, and people interested in that particular article (including, very likely, some of the people who helped write it) are likely to see your question there. Chuck 22:37, 10 January 2006 (UTC)
You are correct, the sentence is gibberish. I will leave a note on the talk page asking for clarification so we can make it clearer. alteripse 11:27, 11 January 2006 (UTC)

Recommend me a book or two on writing programming language interpreters...

So I'm a recent college graduate, I should be getting my Bachelor Science degree in Computer Science in a few weeks after my university finishes processing all my records and stuff.

One of the things I never, ever, ever got the chance to learn was writing compilers, or at least interpreters (it's probably easier to learn interpreters first before attempting to write a compiler for any given language, yes?). Sure, I did write a simple calculator program that allowed for parenthetical notation using a stack which gave me a very basic and simple idea of how parsers work, but that hardly was enough experience to dive in and attempt writing an interpreter.

Local bookstores aren't exactly filled to the brim with books on advanced topics like these in their Computing aisles, so browsing and leafing through the pages before I buy isn't necessarily an option for me. I notice there's many books on Amazon.com, but considering how freakishly expensive they all are, I'd rather not empty a paycheck on a ton of books about writing compilers or interpreters. Can someone with experience in this subject recommend one or two -definitive- books that cover most of what I need to know? I've read customer reviews on most of what I saw, and there seems to be serious pros and cons to all of these sources. A frequent complaint about "the dragon book" is that it doesn't cover object-oriented languages, but I'm not interested in that anyway. And some people say it's easy to understand, other people say it's convoluted and mazey in its explanations. And would buying a book on -compilers- be overkill if all I want to do is dabble in writing my own -interpreter- (I have, specificially, LISP or something LISP-ish in mind) from scratch?

Sorry if this question is worded in a rather roundabout manner. I just want to teach myself the general science and fundamental theories of writing interpreters and/or compilers so I have something that's actually substantial on my résumé, which is currently populated by tumbleweed, dust, and a couple of lazy cows, but I'm not about to spend well over $500 on a whole bunch of books on this subject, of which only one or two might actually be easy to comprehend. --I am not good at running 21:57, 10 January 2006 (UTC)

Compilers: Principles, Techniques and Tools is a classic on compilers (and parsing, which you will also need for an interpreter). 21st Century Compilers is supposed to be it's successor. (Academic) books are a lot cheaper in Europe, so if you happen to be in the neighbourhood... —Ruud 22:28, 10 January 2006 (UTC)
A useful companion book for that is Lex & Yacc, which is a practical guide to using the most common parser generator tool. It's not cheap, of course :( --Robert Merkel 01:44, 11 January 2006 (UTC)

For interpreters, Structure and Interpretation of Computer Programs by Abelman and Sussmann is the classic textbook (especially if you like Lisp). Gdr 23:05, 10 January 2006 (UTC)

They're a real "work-in-progress" at the moment, but you should check out Wikibooks, a source of free online textbooks written by volunteers as a sister project to Misplaced Pages. They have a book on wikibooks:Compiler Construction. And when you're an expert on writing compilers, you can help rewrite the text book! --Canley 23:15, 10 January 2006 (UTC)


I can always recommend the Art of Computer Programming, but unfortunately the Volume that handles compiler technique is not yet written. helohe (talk) 23:55, 10 January 2006 (UTC)
Perhaps it tells you something about the difficulty of writing about language processors. The Art of Computer Programming was supposed to be a book about writing compilers. 'Strue. And Knuth started writing it in 1962, and he hasn't got to the part about the compilers yet... --Anon, 04:52 UTC, January 11.

Starry Decisis

In the Alito confirmation, they keep saying something latin that sounds like the above. What's it mean? Black Carrot 23:04, 10 January 2006 (UTC)

See stare decisis. Gdr 23:05, 10 January 2006 (UTC)
Which would have been an appropriate question at the language desk. hydnjo talk 00:42, 11 January 2006 (UTC)
Sorry about that. Black Carrot 01:12, 12 January 2006 (UTC)
Of course, that only becomes clear once you know what it is. Asking a question in the "wrong" place is no crime. - Nunh-huh 02:25, 12 January 2006 (UTC)
True, but I could have guessed from context that it wasn't a science question, and language really would be the best place for it. I just wasn't thinking. 'Course, didn't do much damage anyway. Black Carrot 04:47, 12 January 2006 (UTC)
Question to hydnjo: Why the italics? Black Carrot 04:47, 12 January 2006 (UTC)

January 11

masses of air pressure

What do masses of air do as they go through the troposphere? Does it have anything to do with expansion or compression?

The troposphere is a mass of air. I think you want Air mass and/or Weather front. —James S. 07:30, 11 January 2006 (UTC)

Electronic Monitoring of the Workplace

Greetings:

Does anyone know of any journal articles or books that provide a survey/list of current/past technologies used in the electronic surveillance of the workplace? (I can think of phone tapping, firewalling and email monitoring, but there must be more than that!!!)

I have used Google's Scholar on this topic, yet all articles that show up talk about the pros and cons, and ethical issues surrounding electronic surveillance at workplace, not about the technologies used in performing electronic surveillance.

Regards,

129.97.252.63 03:29, 11 January 2006 (UTC)

One I've heard of is using computers with voice recognition software to determine whether "private phone call" words are being used by employees on the phone, versus "work-related words". This allows mgmt to have some idea how much time people spend each day on private phone calls without anyone actually eavesdropping. Of course, video cameras are in widespread use in many industries, ostensibly to watch customers, but frequently aimed at cashiers, etc., not at the customers. StuRat 05:30, 11 January 2006 (UTC)
Thanks! 129.97.252.63 04:31, 12 January 2006 (UTC)

WAOL?

Can AOL run without WAOL? This is nonsense. I have a cable modem but chew up 90% of my bandwidth and system resources with this dinasaur of a browser thing, does anyone know of a way to connect to an AOL based cable modem, without the AOL "shell"?--172.151.77.58 03:58, 11 January 2006 (UTC)

Have you considered getting another ISP? hydnjo talk 19:43, 11 January 2006 (UTC)

motion of electrons

why do electrons revolve around the nucleus??? From where do they get the energy to revolve??? if electorns do revolve around the nucleus,then why dont we feel a vibration when we touch a substance??? Thanks for spending u r valuable time in reading n answering this question. — Preceding unsigned comment added by 210.214.168.155 (talkcontribs)

Your question tells me that you have a meager and unsatisfactory understanding about the subject of your question. Start with reading Particle physics and then follow some of the links there. You will, after that, have some questions to ask here and we will welcome them. hydnjo talk 04:39, 11 January 2006 (UTC)
That was a bit uncalled for. Unsatisfactory according to whose standards? Meager according to whose yardstick? People asking questions are implicitly acknowledging their understanding is less than they would like to to be. That's why they ask the question in the first place. JackofOz 07:36, 11 January 2006 (UTC)
You're right, that was a bit uncalled for and I apologize to the questioner. hydnjo talk 17:32, 11 January 2006 (UTC)
I agree; the questioner's "unsatisfactory understanding" is the reason for the question. I'm not sure if Particle physics is such a good place to start, but Atomic orbital, while completely on-topic, is far too advanced to serve this questioner's purpose. How's this:
  • Electrons orbit the nucleus because they are attracted to the positive charge of the nucleic protons, but as fermions they are not capable of occupying the same phase space as the nucleons, so thanks to wave-particle duality, they form a three-dimensional standing wave in orbit about the nucleus instead of coliding with it.
  • There is no energy expended in electron orbitals, because as the smallest form of ordinary matter, electrons encounter no friction, drag, or similar resistance. They stay in orbits because of their electric charge attraction to protons. If they are disturbed, they either leave orbit, ionizing the atom or molecule, or enter a different excitation state, from where they might release a photon to return to their ground state. This is why you see light when crushing Wint-O-Green LifeSavers in the dark (try it!)
  • To begin with, the tiny size of even the largest electron orbital, on the order of a couple Angstroms, is about a millionth of the diameter of the neurons with which you sense physical vibration. But electron orbitals are neutral with respect to mechanical vibration because of their nature as a standing wave of charge-balanced fermions. Moreover, all atoms and molecules -- every bit of matter in the world except fire -- has this same nature. Even if electron orbitals did exert a mechanical force, it would be dwarfed by the thermal vibration of molecules which produces Brownian motion. —James S. 07:55, 11 January 2006 (UTC)
Rather than beat each other with sackcloth, it would be interesting if the questioner found *any* of this useful. --Zeizmic 21:23, 11 January 2006 (UTC)

chimeric two fathers

Has there ever been documented a chimeric (especialy human) with two different fathers? ~~zh

  • It is not possible for an mammalian egg to be fertilized twice, once the ovum fuses with a single sperm cell, its cell membrane changes, preventing fusion with other sperm. If by some weird chain of events two sperm made it in, further cell division to make an embryo would be a problem as there would be 3 sets of chromosomes.--nixie 05:15, 11 January 2006 (UTC)

Thanks Knowledge Seeker, but I don't see anything in that article that talks about a chimera with two fathers, it only talks about having different cells (presumebly both lines from the same parents)~~zh (p.s. thanks nixie too for your try)

      • I'd imagine that its highly unlikey that you could get a tetragametic chimera with two fathers unless you were really trying - female on fertilty drugs to release multiple ova and multiple sexual partners in succession, and even then there is only a tiny chance of it occuring.--nixie 05:36, 11 January 2006 (UTC)

Thank you nixie but dont forget there are 7,000,000,000 people in the world ~~zh

You're right, zh. The rate of heteropaternal superfecundation is very low, and the rate of chimera formation is also probably very low, so the chances of them both happening are very low indeed. I would assume, though, that it must have happened more than once in the 150,000 or so–year-history of our species. But as Nixie says, it would be much more like if one is trying to do it with multiple sexual partners and fertility drugs. — Knowledge Seeker 06:05, 11 January 2006 (UTC)

Why do dogs chase cats?

What is the explanation for this phenomenom? Thanks

Don't dogs chase everything squirrels, cars, bikes? Maybe there are more cats so it just seems like they chase cats more often? David D. (Talk) 05:43, 11 January 2006 (UTC)
Dogs chase things, especially potential prey, because of their instincts as predators. There might be a bowl of kibble waiting for them in the doghouse, but their genes allow them no more resistance to the chase than yours allow you to resist daydreaming about attractive members of the opposite sex. —James S. 08:26, 11 January 2006 (UTC)
I'm strong enough to resist my daydreaming, thank you very much! Anyway, civilisation is not the not having of uncivilised thoughts, but what you do with them. Aparrently dogs aren't civilised. :)
But somewhat more seriously, why do they chase cats? I thought carnivores didn't eat carnivores. Potential competitors? Or are they defending the territory? Of course, dogs are pretty degenerate when it comes to natural instincts, so that's not likely to be a very good explanation of their actions. They're extra fierce around their home turf, but can be agressive elsewhere too. DirkvdM 10:37, 11 January 2006 (UTC)
One major reason is that most cats run away from them. Those cool cats that don't move when they see a dog are merely studied with some curiosity. David Sneek 12:49, 11 January 2006 (UTC)
Don't dogs also chase other dogs, and people, when their territory is challenged? Black Carrot 13:06, 11 January 2006 (UTC)


Well,they do chase people and other dogs sometimes,but it seems like dogs are chasing cats whenever they see them...Etc.when dog see another dog or man,he may just ignore it,or play with it,but when dog see a cat,its a must that he will chase it...That was my question...Thank you again 194.106.189.134 00:04, 12 January 2006 (UTC)

This is not the case in my experience of dogs. Do cats have the same instinct with mice? See this link for refutation.  ;-) David D. (Talk) 00:09, 12 January 2006 (UTC)
Awwwwww! Black Carrot 00:55, 12 January 2006 (UTC)
Seriously, though, dogs don't always chase cats, and cats don't always chase mice. I've never owned a dog, so I can't shed much light on that beyond my above experience with those of neighbors, but I do know cats. My family has owned quite a few cats over the years, with a wide range of habits and temperaments. There have been quite a few avid hunters and huntresses who would gladly stalk, kill, and sometimes leave on our porch anything smaller than they were, including but not limited to: mice(we tried to take care of some twice, they didn't last long), rabbits(funny story there), baby rabbits(one of our early cats cleaned out the entire area, none left), smaller cats(more a territory thing), squirrels, birds, lizards, roaches, moths, string, leaves, points of light on the ground. We have one now that is vigorously opposed to any form of food not hard, bread-based, and dispensed from a bag, and another who, though he chases everything, apparently has no idea that small animals are edible. Considering the variety in cats, and their general love of slaughter if they like killing at all, I suspect they used to chase mice and rats constantly and exclusively mostly because that was the main type of vermin available. I would bet, similarly, that most dogs chase cats who are trained to chase everthing, and as seen above, not all chase anything. Black Carrot 01:10, 12 January 2006 (UTC)

Quarks

What occurs after a down quark switches to an up quark?

In order for that to occur, a weak interaction must take place. The conservation of mass dictates that one up quark worth of mass must be converted to energy, and a positron's worth of charge must be consumed, somehow. I think it would count as a "weak decay" were it not for the charge difference. What makes you think that a down quark ever does become an up quark? —James S. 08:47, 11 January 2006 (UTC)
Er...isn't that what happens when a neutron undergoes beta decay into a proton, electron, and electron anti-neutrino? I'm assuming that's where the questioner got the idea from. The change from the -1/3 charge of the down quark to the +2/3 of the up quark is balanced by the emission of the electron. — Knowledge Seeker 09:00, 11 January 2006 (UTC)
Ah-ha! I thought there was a good reason for the question! —James S. 09:38, 11 January 2006 (UTC)

Two penises

Don't ask why, but a friend of mine wants to know what the medical name would be for the condition of having two penises (presumptively we're talking about humans here). Anyone know? --Dante Alighieri | Talk 06:12, 11 January 2006 (UTC)

why? -User:Lommer | 06:20, 11 January 2006 (UTC)
Diphallia got it from google. David D. (Talk) 06:32, 11 January 2006 (UTC)
Note that some creatures always have two, like sharks. StuRat 07:18, 11 January 2006 (UTC)
"It is commonly mistaken that all sharks have this condition, but in reality they have a pair of "claspers" which serve a reproductive function." --Diphallia article
Two guys? Sorry. :) DirkvdM 10:38, 11 January 2006 (UTC)
Perhaps Dante's friend was playing an old edition of Trivial Pursuit that included the question "What does a man have if he suffers from diphallic terata?" and was suspicious of the answer given. Note: I'm quoting that from memory and it was 20 years since I came across the question. What is supposed to be the same edition, in the version of the game sold in my country, doesn't have it. It stuck in my mind not only because I didn't think they would have dared to ask about that, but also because "terata" didn't sound like the right form; but I could be wrong. --Anonymous, 16:52 UTC, January 11, 2006.
Trivial Pursuit also asked what polyorchidism is. Maybe the writers were just stuck on that topic. --Kainaw 02:01, 13 January 2006 (UTC)
"Brokeback Mountain". Ba-dum-bum. Thank you. We'll be here all week. - Nunh-huh 02:23, 12 January 2006 (UTC)
I prefer to call it "Bareback Mountain", in honor of those gay cowboys who apparently enjoyed "riding bareback". StuRat 06:26, 12 January 2006 (UTC)
Heh. Black Carrot 04:42, 12 January 2006 (UTC)

molecular biology

define below plasmids:

           pWWO plasmid.
           pBR322 plasmid.
           pJLR200 plasmid.
Those are designations of plasmids: pWWO database record, alternate pWWO record -- I can't find the other two in databases; only mentioned in passing in the same Google search you've probably already done. —James S. 09:55, 11 January 2006 (UTC)

Health effects of rapid temperature changes

Are there any health effects of having your body undergo rapid changes in exterior temperature? For instance, at the end of a (warm/hot) shower, briefly turning the water to "cold" before turning it off, or going from a sauna into the snow (or even a frozen lake!!) and back again? Personally, I feel invigorated after the former (and am not brave enough to try the latter), but was wondering if this kind of rapid cooling off had any other benefits? I presume it's not harmful (except perhaps by causing a heart attack through shock in extreme cases), but is it in some way beneficial beyond the psychological feeling of being refreshed? TIA! — QuantumEleven | (talk) 12:37, 11 January 2006 (UTC)

Looking at this, I stumbled upon Warm-blooded, which is neat, and worth reading. Nearly all serious effects have to do with altering the core body temperature, and a quick roll in the snow after a sauna isn't going to do that. --Zeizmic 15:59, 11 January 2006 (UTC)
Well, it is putting stress on the body, and if you were particularly susceptible to heart attacks, this is the type of thing which might trigger one. For most people though, this should not cause any problems. StuRat 02:16, 12 January 2006 (UTC)

Electricity from lightning

I see that the Empire State Building in New York gets struck by lightning about 15 times a year - why can't we wire up the roof to a big battery & catch all the energy put out by a lightning bolt? AllanHainey 12:48, 11 January 2006 (UTC)

Once again I went to THE BOX, and typed in 'lightning'. Now, I know the answer and I'm not going to tell you.... --Zeizmic 13:01, 11 January 2006 (UTC)
I think there was an episode of Transformers where they did this ... Proto t c 13:08, 11 January 2006 (UTC)
I did read the Lightning article but it didn't answer my question, if you managed to figure out an answer from the complex scientific bits of it please let me know as I didn't really understand some bits of it. AllanHainey 14:25, 11 January 2006 (UTC)
A battery can only be charged gradually, using a continuous supply of electricity. A flash of lightning happens too quickly for it to be of any practical use. Also, lightning takes the path of least resistance, so even if you could stick some sort of storage device in its path it would simply avoid it.--Shantavira 15:30, 11 January 2006 (UTC)
Having read the relevant sections is always a good thing to mention. You will have noticed what happened to the various people who tried to heat their houses with wired kites in thunderstorms. It's just too friggin' dangerous! That's the answer without the complex bits. On a scientific level (to inflate my opinion of myself), we engineers always have a problem with converting a high-density energy source to a lower density. Take nuclear power; you can't take useful energy out of a nuclear bomb! You have to go through all sorts of complex bits to fire up lightbulbs with it. --Zeizmic 15:52, 11 January 2006 (UTC)
My experiment doesn't use lightning. I work on the 11th floor. I put an antenna the pressure-hole in my window frame and connected it by an insulated wire to a multimeter. I connected the other end to the sink's cold water pipe. I got almost no voltage (0.4V) and almost no amps. Then, when the wind picked up the voltage picked up (just breaking 3V once). I did it again now and then, but I never get any amperage of note and the voltage isn't high enough to reduce it and create some amps. Perhaps you can think of a way to trickle a charge a battery with a similar setup. --Kainaw 21:26, 11 January 2006 (UTC)
Some people over at the Halfbakery have discussed this. Before you get too excited, I suspect that there's not as much energy in lightning as people think. "500 megajoules" sounds big, but it's only 140 kilowatt-hours, which is worth about 100 quid at UK prices. You would have to capture lightning over a huge area to make a scheme worthwhile. --Heron 22:08, 11 January 2006 (UTC)
Imagine your big battery comes to life as Frankenstein's creature did ? --Harvestman 22:15, 11 January 2006 (UTC)

Hybrid Car

Please give me the name of the world's first Hybrid car? --61.1.228.25 13:43, 11 January 2006 (UTC)

See Hybrid vehicle. The history section there should help you. Thryduulf 14:37, 11 January 2006 (UTC)

What does boron react with?

hydrogen, flourine, chlorine, bromine, iodine, oxygen, sulphur, nitrogen and anything else with the right valence and electronegativity. James S. 18:15, 11 January 2006 (UTC)

Webster's defintion of life and person in 1847

I am looking for and online dictionary that would have definitions from Meriam Webster (started in 1847) or other dictionaries that would included defintions of life and person at the time or even four years before 1847.

Thanks, Ken

email me at (Ever heard of "spam"?)

This is a Misplaced Pages:Reference_desk/Humanities question, not a science question. —James S. 22:09, 11 January 2006 (UTC)

I could not get anymore than I already have. If I do, oh well. Thanks anyway. If it were my primary account then I would not have used it. Thanks mommy.

Software for creating simple drawings and figures

I was just asked the following question: "What's the best, easiest software that would allow a novice to create a simple drawing with words and images?" And suggestions? Guettarda 19:11, 11 January 2006 (UTC)

Going with a typical Windows platform, likely either Paint or PowerPoint (or another presentation program) — Lomn | Talk / RfC 19:16, 11 January 2006 (UTC)
Inkscape - it's free, fast, and you can be productive with a minute's worth of learning; best of all it's got lots of power under the hood (unlike things like paint) so you won't have to drop it and learn something new when you want to do something more complex. -- Finlay McWalter | Talk 00:40, 12 January 2006 (UTC)
FAST? You must be joking! Inkskape has the slowest GUI I've ever seen, and buggy as well. The program itself is nice, but you probably need Pentium 3000 or higher to use it.  Grue  11:24, 12 January 2006 (UTC)

ati2dvag.dll

Hello, and I hope you can shed some light on this. Closing the lid and walking away is supposed to be supported on my Dell Inspiron 5100 (Win XP). Opening the lid is then supposed to restore whatever was running. But consistently when I do so and come back a couple of hours later, the screen is blue. The error message points a finger at ati2dvag.dll. I've looked on the Web for information about this component and what to do about the problem, but the information is way over my head. Of course I can always reboot and use my computer without problems if I don't close the case and go away with programs running. I've done so 6-8 times. So maybe I should just let it be. But I'm curious: what's happening? Is there anything I could do to make a fix? Any technical knowledge I used to have was at a considerably higher level. Thanks, Halcatalyst 19:51, 11 January 2006 (UTC)

It's just as likely that you are overheating. You won't get a good answer here, or perhaps anywhere. Sorry. --Zeizmic 19:56, 11 January 2006 (UTC)
Judging by the name of the dll, it looks like it's part of your video card driver. I'd suggest upgrading your ATI driver. enochlau (talk) 23:36, 11 January 2006 (UTC)
  • I have XP/SP2. Checking out the system information, I see the following devices: ACPI Lid, ACPI Power Button, ACPI Sleep Button, ACPI Thermal Zone. Windows says they are all working, but Windows has been wrong before <g>. It didn't tell me anything about ATI. I'd appreciate any other insights or suggestions. Thanks, Halcatalyst 02:31, 12 January 2006 (UTC)
  • Looking further, I discovered my laptop has the Mobility Radeon 7500c (ATI) video driver, and that Windows had a wizard I could use to update it. The wizard said it would check locally, the CD if I had it, and even go out to the Web. But since I didn't produce the CD, it just gave up after searching locally. Now I'm trying to find the CD, which, like any dumb user, I put away somewhere I can't remember now. Halcatalyst 02:47, 12 January 2006 (UTC)

Just a quick look at Google indicates many people have problems with ATI cards. Dell uses ATI because they are cheap. It helps them the price low on their products. Cheap hardware, buggy drivers and a brain dead operating system are almost guaranteed to produce problem like this. You get what you pay for. I have also found that suspend and power management are problematic functions on computers to start with. I've seen it cause no end of problems. On my own boxes one of the first things I do is go in the BIOS and disable as many of the power management "features" I can. On a laptop, if you don't plan on using it for a couple of hours shut it down.--Puck 16:00, 12 January 2006 (UTC)

I doubt it's an overheat - your error message indeed looks like graphics card trouble. Something you can try - what's your computer trying to do when you close the lid (check Control Panel -> Power, there should be a tab which controls what your computer tries to do when you close the lid). Stand by? Hibernate? Try doing these things manually (Start -> Shut Down -> Stand By / Hibernate), and see if they work correctly. If they don't, you've found the problem - your graphics card driver doesn't support one or the other function. If they do, then it seems to be a problem with the lid closing... in that case, try standing by / hibernating the computer and then closing the lid, it doesn't take a lot of extra time, and it might work well then. In any case, updating your driver is probably a good start - check out ATI's website and find the latest driver that supports your card (it's a bit old, so you may have to dig around a bit). Good luck! — QuantumEleven | (talk) 17:12, 12 January 2006 (UTC)

Thanks to all for your responses. Halcatalyst 14:36, 13 January 2006 (UTC)

  • This morning, after settting the power button to do nothing when the lid closes, I closed the lid with programs running. A couple of hours later, pop the lid and voilà! everything saved and working as designed. Halcatalyst 17:40, 13 January 2006 (UTC)

Long-distance communication

I was reading somewhere recently that the long-distance communication common in sci-fi books/movies/etc. (i.e., communication between people/spacecraft at different planets, different stars, different galaxies) would be impossible because the limit to the speed of light means that communication between even Earth and Mars would have a minutes-long delay, and across stars would have a years-long delay. But isn't there something in quantum physics where making one particle spin one way makes another particle spin the other way at the exact same time, no matter how far away the particles are? Wouldn't it be possible to communicate via these spins (maybe one spin=0 and the other =1 and then read it via computer)? Zafiroblue05 20:23, 11 January 2006 (UTC)

It's called quantum entanglement - you might want to read the article on it. To summarise, you can transmit information faster than light, but not useful information. Don't ask me why! --Heron 20:58, 11 January 2006 (UTC)
Why? I was given the glove example. We both get a box. One has a right hand glove and the other has a left hand glove. We travel to opposite sides of the Earth. I open my box and see a right hand glove. Faster than light, I gather information about the contents of your box on the other side of the Earth. It isn't useful information, but it is information. Now, don't ask me why this precludes quantum entanglement. --Kainaw 21:15, 11 January 2006 (UTC)
Same as Heron stated : a single glove is not very useful. --Harvestman 22:05, 11 January 2006 (UTC)
With quantum entanglement, you can't affect the state of the entangled pairs. More info here.James S. 22:14, 11 January 2006 (UTC)
As I understand it, the gloves (prior to be being observed) would have both been in the wavelike state inside the box, so the probability field is distributed more or less evenly, allowing the gloves to have the effect of either left-handed gloves or right-handed gloves from inside the box. As soon as the state of one glove is known, the probability field of the other glove is restricted, which limits what the glove can affect (or do). I know the commonsense version seems like the only way it could happen, but those knowledgeable sciency types say QM is real and it doesn't make sense to anybody. Tzarius 22:17, 11 January 2006 (UTC)

Any form of long distance communication for which the phone company can't bill is clearly illegal and any physicists who disagree will be arrested. StuRat 06:43, 12 January 2006 (UTC)

Coloring around the anus

Our article on the anus states: "Anal bleaching is a relatively new West coast phenomenon where the perineum, which darkens over the years, is lightened for a more youthful appearance." Although the article doesn't say why this coloration happens. What is the cause of this? My first guess would be staining by the feces that pass by that part of the skin but if the skin is shed, why would it become discolored more as we advance in age? Dismas| 20:15, 11 January 2006 (UTC)

Maybe they do, but there is still no ambigity because nowhere except on our beloved West Coast could such a thing be conceived! alteripse 11:19, 12 January 2006 (UTC)
I dunno, they're pretty wild and wacky people in Perth and especially Geraldton, Western Australia --Robert Merkel 11:49, 12 January 2006 (UTC)
It wasn't my markup, I just copied and pasted from the page in question. Dismas| 15:56, 12 January 2006 (UTC)
Your theory sounds reasonable. Specifically, it might be stained by bile in the feces. StuRat 09:33, 13 January 2006 (UTC)
Next question! --Zeizmic 21:24, 11 January 2006 (UTC)

Get the patent on that. You can make millions by making people feel inadequate. Especially politicians. Maybe you can get Arnold to do tv ads. GangofOne 17:20, 12 January 2006 (UTC)

Smokeless tobacco

Is there any known research that using smokeless tobacco increases sex drive in males? Anyone every hear of this in single case studies?

I don't think there is. As far as I know, any research on smokeless tobacco would also have to be conducted on smoking tobacco as well, which would possibly yield the same results. However, I suggest you check Ig Nobel and see what they have, considering the line of research this is. --JB Adder | Talk 21:50, 11 January 2006 (UTC)
Nicotine is a stimulant, which will increase activity in general. Poking around on Medline unconclusively suggests that nicotine might affect testosterone levels but not necessarily libido. —James S. 22:51, 11 January 2006 (UTC)

No and No. alteripse 05:25, 12 January 2006 (UTC)

Electricity

Who is credited with being the person who discovered electricity?

This is an encyclopedia, see electricity. Dismas| 23:20, 11 January 2006 (UTC)
This is the reference desk (science section) at the Misplaced Pages Encyclopedia and some part of your question may indeed be answered at the electricity article. There you will find that a form of electricity was known to the ancient Greeks. hydnjo talk 23:56, 11 January 2006 (UTC)
Dear Mr. Serious. We also have a duty to try to get the people to read the upper section of this reference desk. The word mollycoddle is being moved to the Wiktionary. --Zeizmic 00:12, 12 January 2006 (UTC)
Mr. Serious being who, Mr. seismic or whomever? And, mollycoddle is as mollycoddle does, ya know!
Hmm, methinks I see Mr. Taskmaster lurking hereabouts, do I not? Oooh and by the way we tremble at your very mini tremble. Please don't be a dick. hydnjo talk 01:50, 12 January 2006 (UTC)

January 12

Computer Question

How can I input data to a computer accurately?

Umm, after you input the data, check it for accuracy. Like, after I write this comment I should look back at my Misplaced Pages input with Show preview to see if my edit looks like I want it to look. I can make this look any way I want it to look. There is no replacement for your looking over your own input to see that it is what you meant to input. hydnjo talk 04:26, 12 January 2006 (UTC)
If there is any way to avoid manual input, that's almost always an improvement. For example, if the data is printed out from some other program, devise a way to send the output to a file, and read it from the new program, instead of manually reentering the data. StuRat 05:11, 12 January 2006 (UTC)
Actually, there is a reasonable "substitute for looking over your own input": that's to enter everything twice (or even more times!) and have the computer compare the two versions, then fix the differences. It's better yet if someone else enters it the second time, as you might have some habitual errors and if you make the same one twice in the same place it won't be seen. But, yes, carefully looking it over is good as well.
There are also tricks to help focus your attention when you are looking it over. Put it aside for a few minutes before you start, so you come back to it fresh; read it aloud as you go, so you don't skip over bits; read it in some other sequence, like backwards (for text) or in single-digit columns (for tables of numbers), or that sort of thing, so you don't think about what it means.
And of course avoiding manual input is even better... if you have a trusted machine-readable source.
--Anonymous, 06:43 UTC, January 12, 2006.

Practice. A lot. I've seen touch typers work at 80 wpm (speech is around 60ish WPM) with zero errors. After a couple of decades of practice. Syntax 18:47, 12 January 2006 (UTC)

Stream Development/Landscape Development

Four stages in a streams development - Mature, Old Age, and a young/new stream

What would the fourth stage be?

could not find an entry pertaining to this, maybe someone can point me too one. thanks.

  1. Youthful
  2. Mature
  3. Old Age
  4. Rejuvinated
See also: and James S. 05:01, 12 January 2006 (UTC)

Lucifer to Iapetus

In the Space Odyssey series by Arthur C. Clarke, the new mini-sun Lucifer is created using Jupiter. What would Lucifer's predicted effects on Saturn and Mars be? Iapetus? Please be sure to include all information you can think of, including radiological effects; climate, tidal force, or orbital changes; etc. Here7ic 04:52, 12 January 2006 (UTC)

It's hard to answer simply because this is purely speculative, rather than science-grounded, fiction. Let's assume Jupiter could really ignite as-is. There would be no orbital changes, as the mass of Jupiter is unchanged. However, Jupiter has only about 1/80 of the necessary mass for stellar fusion, so any estimate of radiological effects, etc, is sheer guesswork: no stars exist on that scale.
If, however, you really want to extrapolate, I would assume that Lucifer has stellar characteristics akin to that of Sol. You could then determine the relative energy reaching a given body like Mars from Sol vs from Lucifer, bearing in mind that while Mars keeps a nearly-constant distance from Sol, it has a widely varying distance from Jupiter. — Lomn | Talk / RfC 05:23, 12 January 2006 (UTC)
Now, if you can/will, please apply a change in Jupiters mass. Perhaps twofold? 198.110.63.66 17:36, 12 January 2006 (UTC)
It's much more fun to play around and discover for yourself. Try a solar system simulator, like --Fangz 20:59, 12 January 2006 (UTC)

Medical Problems

How do you get a stye in the eye?

Search first - it's quicker. If you use the search box on the left of the screen, you'll quickly find stye; they are the result of a bacterial infection. They can be quite uncomfortable (I know, I had one on Christmas Day)...--Robert Merkel 07:33, 12 January 2006 (UTC)

hearing different sounds simultaneously

i have read that sound reaches from the source to the receiver by the vibration of air particles.in that case when two people are speaking at the same time,when the vibration of air paticles from first speaker reaches my ears the vibration from the second speaker will also reach my ears at the same time.then they shold collide with each other and i shouldnt be able to hear their voices.But this is not what is happening.HOW????thanks for spending u r time in responding to my question.

When two waves overlap they don't necessarily cancel each other out. If you think of sound waves as sine waves, they would cancel each other out only when 180 degrees out of phase. If they were in phase with each other, they would actually reinforce each other to double the volume. To put it another way, a sound combined with the same sound will double the volume, while a sound combined with the opposite sound will cancel each other out. Since two different people speaking will generate two different sounds, parts will be cancelled and parts will be reinforced. And, since the two sounds will reach each ear at different times, different cancellation and reinforcemnt will happen in each ear. Your brain can usually figure out and fill in the missing parts, but, as you know, it is a bit more difficult to hold a conversation when other people are talking around you, since your brain can't fill in all the gaps. StuRat 05:52, 12 January 2006 (UTC)
This is true, but misses an important point: cancellation only happens when the frequency (pitch) of the two sounds is identical. Sound waves of different frequencies will not interfere with each other; the air molecules will move in a way that combines the two wave motions. As mentioned at ear (but, oddly, not at cochlea or organ of Corti), the ear has separate sensors that respond to different frequencies of sound; if a tone of 200 Hz and one of 300 Hz are both sounded at once, the combined wave motion will still stimulate the two corresponding sensors and you will hear a combination of both tones (like a musical chord, although that term normally implies that there are at least three tones). Speech is much more complicated, with multiple tones sounding at once from different parts of mouth and throat; interference simply is not an issue. --Anonymous, 07:00 UTC, January 12, 2006.

Thank you !!!

Nasal snuff and health

What are the health risks and benefits of (dry) snuff? Mysteriousinventors 05:53, 12 January 2006 (UTC)

Benefits: none.
Risks: Cancer. StuRat 06:05, 12 January 2006 (UTC)
Actually the Tobacco article says that it can help with hay fever, by clogging up the nose. I'd be careful about the cancer claim. The links between non-smoking tobacco and cancer are less clear. For instance the link between Snus and cancer is still hotly debated, with many inconclusive studies. (to the extent that the Swedish government had the 'causes cancer' warning labels on wet-snuff products replaced with 'damaging to your health' ones). I don't advocate nicotine use, but as an alternative to smoking almost any other form of nicotine seems far less hazardous. --BluePlatypus 06:24, 12 January 2006 (UTC)

I suppose their is a benefit to me of other people using snuff. They will get cancer and die without ever giving me cancer, unlike with cigs. StuRat 06:37, 12 January 2006 (UTC)

Cell referencing in Excel

Hi. Let's say I have a row full of numbers (row A). Using the vlookup function I want to obtain the cell that a certain value can be found. So for example, if row A column 3 has the number 17, and I search for the number 17 using vlookup, I want the result to be RC (or whatever the syntax may be), so the result I am looking for is the cell itself, not the value contained in it. Is this possible to do? If so how? Thank you. - Akamad 07:04, 12 January 2006 (UTC)

Never mind, I worked it out. - Akamad 07:36, 12 January 2006 (UTC)
Actually, scratch that, the way I did it was a long winded way, and I'm hoping there is an easier way so I'll put the question back on the table. Thanks :-) Akamad 08:33, 12 January 2006 (UTC)

Computer

How can i input data to a computer accurately?

Learn touch typing. Seriously, you're going to have to be a bit more specific if you want a useful answer. What kind of data? What is the source of this data (your head, handwritten text, printed text, your boss's voice, something else entirely)? --Robert Merkel 07:42, 12 January 2006 (UTC)
one (expensive) method for ensuring accuracy is to have the data input two times (once each by two different people) and then compared. Where the two agree, they are likely to be correct; where they disagree, a further look is in order. - Nunh-huh 08:17, 12 January 2006 (UTC)

Read way above: don't double post and be specific. DirkvdM 11:27, 12 January 2006 (UTC)

radio frequency

How does radio frequency work without interference from other frequencies?

Radios would use a filter to filter out the unwanted frequencies. This website shows some pictures of waves in different frequencies. The second picture shows a graph with 4 different frequencies. So a radio can, on this example, filter out all frequencies except that at 1kHz (if you wanted to "listen" to the information provided on the 1kHz band). - Akamad 08:52, 12 January 2006 (UTC)
Waves of different wavelengths can pass right thru each other without affecting one another. You can see this with water waves sometimes. This is a basic feature of waves. StuRat 08:52, 12 January 2006 (UTC)

computer

How can i identify and correct my own mistakes after i input data to a computer?

Read through it and check to see if you inputted what you wanted to. - Akamad 08:44, 12 January 2006 (UTC)
You could also consider doing your own homework. --Robert Merkel 08:44, 12 January 2006 (UTC)

If you can print it out in the exact same format as you had to start with, you can hold the two pages up, one on top of the other, to the light, and any differences should jump out at you. There is also a "diff" function on many computers that will find any differences in the two, automatically. However, again they must be in the same format for this to work. StuRat 08:58, 12 January 2006 (UTC)

Computer question

How can i add reference codes when required?

micosoft word

how to add reference codes in Microsoftword?

Dog and Fox

No, it's not a question about pub names. Can you cross a fox with a dog? Using the same logic applied to ligers, zonkeys and wolphins, I looked up both fog (which is, of course, something else) and dox (no dice). And I couldn't see anything on the fox or dog articles. In the canine hybrids category, I found wolfdogs, coydogs and coywolfs (coywolves?) - again, no foxdogs or dogfoxes. So, could this be done? Proto t c 09:47, 12 January 2006 (UTC)

And here I thought this was about jumping. Femto 12:41, 12 January 2006 (UTC)
I don't think so. Foxes have 34 pairs of chromosomes, dogs have 39 pairs, so they don't match up. David Sneek 10:09, 12 January 2006 (UTC)
David is right, interspecific hybrids are only possible if the chromosome numbers are fairly similar, eg donkeys has 62 and horses have 64, so you can get the sterile mule with 63.--nixie 10:17, 12 January 2006 (UTC)
Aha. That makes sense. God bless List of number of chromosomes of various organisms. Follow up question - both cats and pigs have 38 pairs of chromosomes - could we have a catpig? Or half-cow, half gypsy moth (cowth? No, wait, moo-th!) And hares have the same amount as humans ... or is the thought of a "human hare" just too freaky? Proto t c 11:55, 12 January 2006 (UTC)
It's probably not just the number of chromosomes that matters, but also the compatibility of the genetic information they carry. The really existing examples you give above suggest that interspecific breeding only works with animals that belong to the same family; the parents of a liger are both felidae, a wolphin's mother and father are both part the delphinidae family, a coywolf's parents are canidae, etc. David Sneek 12:26, 12 January 2006 (UTC)
That makes sense. Thanks, David. No cow moths (I'm going to copyright moo-ths, just in case) in the forseeable future ... bah. ;) Proto t c 13:04, 12 January 2006 (UTC)
If you're not restricting this to conventional breeding and allow genetic engineering, there are spidergoats. Femto 13:22, 12 January 2006 (UTC)
That...is...AWESOME!!! Black Carrot 18:35, 12 January 2006 (UTC)
Other than ethics, morality and queasiness, could a human mate with a chimpanzee and produce viable offspring? User:Zoe| 00:56, 13 January 2006 (UTC)
It was going to be tried, see Ilya Ivanovich Ivanov (biologist), but the experiments never happened. Humans have 23 sets of chromosomes and the great apes have 24, since great apes can't form hybrids with each other even with idential chromosome numbers, humans are possibly also too different to make human/primate hybrids.--nixie 01:05, 13 January 2006 (UTC)
Actually accordingly to Ivanov's article, he did inseminate female chimpanzees with human sperm. Nothing came out of it, and plans to try inseminating human women with chimp sperm never panned out. Isomorphic 06:57, 13 January 2006 (UTC)

Catalsyt

I would like to know the name of a catalyst that can convert molecular hydrogen to atomic hydrogen i.e. nascent hydrogen and how to use the catalyst.

I suggest you take a look at this page, but don't think ti'll be that easy to do it in your basement... Mariano(t/c) 14:41, 12 January 2006 (UTC)

Why are Marsupials confined to the Australian continent?

They aren't. But most species occur there. See Marsupial, specifically "There are between 260 and 280 species of marsupials, almost 200 of them native to Australia and nearby islands to the north. There are also many extant species in South America and one species, the Virginia Opossum, native to North America." Rmhermen 15:45, 12 January 2006 (UTC)

They can't swim well enough to get off. That's where they evolved. GangofOne 17:25, 12 January 2006 (UTC)
Or, more to the point, the placental mammals that seem to have driven them nearly extinct elsewhere couldn't swim well enough to get to Australia, so the marsupials were left in peace there. —Ilmari Karonen (talk) 00:26, 13 January 2006 (UTC)
Not quite: They evolved when Australia was still connected to South America. When the latter eventually connected to North America, species from the two continents could intermingle, and many marsupials didn't survive the competition. Some are doing quite well, however, as my opossum-hunting dog could attest. – ClockworkSoul 13:46, 13 January 2006 (UTC)

Units of Permeability

Permeability is measured in Darcies (D)or milliDarcies, based upon the work of Henry Darcy (circa 1856), but who in more modern times, re-wrote the equation in the familar form and coined the descriptive name (Darcy) of the unit? I have serched the net to no avail so far??

Any help is much appreciated

Craig Lindsay

---207.218.155.21 13:40, 12 January 2006 (UTC)

Then you didn't search enough. See darcy. ☢ Ҡieff 13:52, 12 January 2006 (UTC)

I did see this page, but it still dosn't tell me my answer. The unit the Darcy was proposed by someone at a later date. Who was it and when? Thanks anyway.

Modular Design

What is Modular Design in computers?

Same as modular design in other things (eg cars, fridges, even furniture). The idea is to build things of easily replacable parts, with standardized interfaces. A computer actually is one of the best examples of modular design - typical modules are psu, processor, mainboard, graphics card, hard drive, optical drive, etc. All are easily interchangeable, as long as you get one that supports the same standard as the one you replaced. I'll go ahead and copy this to the talk page there so some one can use it to improve the article. TERdON 14:37, 12 January 2006 (UTC)
You can find some more info here and here. (Maybe Modular design should be a redirect?) David Sneek 14:41, 12 January 2006 (UTC)
I think not. Those pages describe modularity in the software world only (or at least that what they should do - according to the title. One of them speaks of as well cognitive science as network biology???). Modular design is a very important concept in manufacturing technology as well. The computer (read: IBM PC compatible) hardware actually is one of the best examples availabe of modular design in manufacturing. Possibly, they could be merged instead, but that really would have to be to a page without a (programming) parenthesis. And the subjects are so big anyway, that there is information enough to support subpages. TERdON 14:51, 12 January 2006 (UTC)

Army worm

Is there another name for the Army worm, or is there no such article in wikipedia ? Wizzy 15:17, 12 January 2006 (UTC)

The army worm is the larva of the Pseudaletia unipuncta moth. There doesn't seem to be an article on it though, but it is mentioned in the maize article. --Canley 22:59, 12 January 2006 (UTC)
Thanks. Wizzy 09:13, 13 January 2006 (UTC)

infra red security system

hey guysCAN U HELP ME WITH A THIS PROJECT I NEED 2 DOO i need 2 make a infra red secuty system just 2 show onan exhibition any ideas on how 2 make one or do u guys have any links???--Iamhungry 15:55, 12 January 2006 (UTC) i want one that is quite simple bcause im not a genius--Iamhungry 15:55, 12 January 2006 (UTC) but im not that dumb you know--Iamhungry 15:55, 12 January 2006 (UTC)

At a guess, I'd start with infrared or electric eye, but I think you'll have better luck using Google to find "electric eye project" or the like. The very quick nutshell is that you'll want an IR-emitting diode coupled with an IR photosensor. Misplaced Pages will likely not have project-style guidelines. — Lomn Talk 16:06, 12 January 2006 (UTC)
Google "electronic kits" and look around. GangofOne 17:33, 12 January 2006 (UTC)

Japan 100 volts 50/60 hertz

Why is one part of Japan wired up for 100 volts 50 hertz and the other part for 100 volts 60 hertz? Pls send answer to (saving your inbox from flooding)

Cleaning lab glassware

I am following a procedure to get lab glassware very clean (for use in amino acid analysis). One step is to 'wash the glassware with 6N HCl'. My question is what exactly does 'wash' mean in this context? Rinse with the acid? Let the glassware soak in acid? Fill it with the acid and rub it with a brush? (I doubt it) Your opinion, please.... ike9898 17:17, 12 January 2006 (UTC)

I'm not sure how clean you need it; in our school labs, cleaning with acid generally means filling it with a small quantity of acid and then swilling it. But it sounds like you are probably using stronger acids than the weak bench chemicals used in school, so I'm not sure of the safety of swilling it around. smurrayinchester 22:31, 12 January 2006 (UTC)
6M HCl isn't that strong, really. In any case, if it just says wash, you're probably only expected to rinse the entire surface with the acid. If you were supposed to soak it, it would say soak. If there's anything on the glass that needs soaking or scrubbing to come off, you probably didn't perform the earlier steps properly. —Ilmari Karonen (talk) 00:20, 13 January 2006 (UTC)
I'm pretty sure that 6 M HCl can burn you badly. Isn't a saturated soln of HCl 11.8 M? ike9898 02:01, 13 January 2006 (UTC)
  • To acid wash for protein work, leave the glassware filled with the acid in a switched on fumehood overnight. Some labs also heat the solution to 70 degrees, but depending on where you are you might need to get occupational health and safety to OK the proceedure. Always use heavy duty gloves, not regular latex or nitrile. Isn't there someone who you can ask about normal lab proceedure?--nixie 03:29, 13 January 2006 (UTC)

Geography. ebb

Is it correct? If ebb in a sea was happen the opposite side of earth is ebb so.? If correct why?

It sounds like you're asking about why high and low tides appear in pairs. Have you read the article on tides? — Lomn Talk 18:03, 12 January 2006 (UTC)
You might also be interested in tidal force; the physics behind this. smurrayinchester 18:05, 12 January 2006 (UTC)

Tsiolkovsky, Konstantin

Do you know HOW he communicated with others, considering his impairment (verbally, sign language, etc)?

He was hard of hearing, not completely deaf. --Kainaw 20:48, 12 January 2006 (UTC)

What keeps clouds up

What forces of physics in the atmosphere keep the water/ice particles together to form a cloud and what keeps the cloud above the surface suspended in the atmosphere? Is the process different on the "night side" of the planet? Does it differ in relatively cold area of the earth vs for instance at the equator Thanks!

All the Best,

Greg

The article Cloud has answers to that. Please read the instructions at the top of this page. Black Carrot 18:27, 12 January 2006 (UTC)

Microsoft Operating Environments

I need to know if an operating evnironment is the same thing as a GUI? If not, was Microsoft the first to create a "True Operating Environment" --208.189.210.6 19:50, 12 January 2006 (UTC)

An operating environment is, as the name implies, an environment from which you may operate the computer. GUI is an acronym for Graphical User Interface. An operating environment may contain GUI items, but it is not a requirement for it to do so. Microsoft was not the first to create either one. --Kainaw 20:46, 12 January 2006 (UTC)
Is there any essential technology (meaning not a different version of something someone else invented) that Microsoft invented? DirkvdM 10:26, 13 January 2006 (UTC)
Essential? No. Every time Microsoft has a new essential item, it existed before in another form - just not as popular as when Microsoft did it. There are only two things that I've heard Microsoft devotees argue about: the registry and COMM. A common registry is sort of a unique invention. I wouldn't call it essential though. As for COMM, long before it existed Amiga did the same thing with ARexx (a type of Rexx) that let programs talk to one another easily. --Kainaw 19:26, 13 January 2006 (UTC)

What does aetiology mean?

See Etiology. --Sum0 20:41, 12 January 2006 (UTC)

Cellphone recharging

I heard a rumour a while ago (maybe 6 months or so), but might have misunderstood the article or something...is it possible to recharge cellphones via a satellite signal? What is this technology called? Thanks for your help! --HappyCamper 22:17, 12 January 2006 (UTC)

Correct me if I'm wrong, but I'm pretty sure it's impossible to send enough energy through a radio signal to recharge a phone. In terms of interesting recharge methods, Motorola introduced a solar recharger for satellite phones a year ago, and there is the inductive power transfer method which involves placing the item on a kind of mouse mat which charges it. --Canley 22:44, 12 January 2006 (UTC)
I wrote a research paper on this in college a while back. Here is the issue: There is enough power in a standard radio signal to power a speaker without any extra energy source. Radio Shack used to sell kits to make these radios (I think they only tuned to AM stations). I believe they called them crystal diode radios.
I used just the antenna/tuner part of them to get a good signal and placed them close to each other to see if any one would have a reduction in power (voltage or amperage) because they were in close proximity to another one. No. They do not. With 20 of them sitting side by side, they all maintained the same power.
Next, I put them in series so each one would theoretically add to the power of the next one. This failed. Once connected to each other, they did interfere with one another. So, I put diodes between them to force a single direction of electricity, but I didn't have small enough diodes for such low power.
My conclusion: If you had a few thousand of these antennas and extremely small diodes to keep them from interfering with one another, you could get enough power to trickle charge a battery. I do not have a cell phone, pager, or laptop. So, I haven't worried about trying to do it. --Kainaw 01:56, 13 January 2006 (UTC)

Also note that Tesla wanted to broadcast power, as opposed to just a signal. It is possible to broadcast large amounts of power, but would be very dangerous and the ability of anyone to tap into the power for free would also make it impracticle. That said, if the power needs for a cellphone can be reduced to an extremely low level, they may not be so worried about the danger and costs, which would be greatly reduced to match. StuRat 09:03, 13 January 2006 (UTC)

Genome Project

Hello! If the human genome was 99% mapped to 99.99% accuracy back in 2000, why do we still have nothing remotely close to a cure for purely genetic diseases? As I see it, there is still no idea where most genetic diseases come from, let alone a cure. What was accomplished and announced with great fanfare back in 2000, if we have not seen any significant benefits 6 years later? I thought that having a complete understanding of DNA would enable us to totally eliminate thousands of diseases, from Down Syndrome to oily skin. What am I missing? Thanks. ironcito 22:24, 12 January 2006 (UTC)

They only got the map, not the directions. Complete understanding of all the processes involved in a complex multicellular organism (such as ourselves) is probably centuries away. Tzarius 22:46, 12 January 2006 (UTC)
Exactly. Knowing where a gene sequence is and even what it does doesn't mean we know how it works or how to stop it doing something harmful. The HGP database will be immensely helpful to science, but medical science works very slowly, and developing drugs takes many years of research and testing. --Canley 22:53, 12 January 2006 (UTC)
On the bright side, your DNA makes for a nifty poster, and those are 100% complete. Black Carrot 23:32, 12 January 2006 (UTC)
  • The human genome project made sense as a "big science" project because many small research labs were using inefficient methods to slowly identify all human genes. One of the "results" of genome projects has been technical. It is now much less expensive to sequence genomes. It is now a goal to be able to determine an all of individual's gene sequences for "$1,000 or less" (PMID 15719589). Predisposition for many human genetic diseases that are already understood could then be diagnosed independent of waiting to see the disease phenotype. This would allow for prevention of disease either by pre-natal screening or behavior modification. Many genetic influences on disease are complex, involving many genes. Now that the human genome sequence is in hand, there are many research studies attempting to better understand complex genetic disease processes. Ultimately, the human genome project has saved money and speeded up the process of studying genes and how genes influence health. There is still much work to be done. --JWSchmidt 23:41, 12 January 2006 (UTC)
  • It might also bear mentioning that the Genome Project did not map all human DNA: its stated goal was to map all human genes. It mapped 99% of euchromatic DNA but did not map heterochromatic DNA. If "junk DNA" has any relation to disease - and we just don't know if it does - the Human Genome project won't help with it. - Nunh-huh 01:17, 13 January 2006 (UTC)

Knowing a genome sequence doesn't make it any easier to develop new drugs or treatments, a few examples

  • Gene therapy for single disorders like Cystic Fibrosis- requires a good gene therapy technique, gene therapy is in development but is still in early stages
  • For multigene genetic disorders like diabetes, scientists are still trying to find out which genes are involved, the sequence should speed up the process. But then they have to work out how the genes involved interact and which ones would be useful for therapy
  • Say there is a enzyme which makes skin oily, and we have identified it in the genome, to make a drug to modify the activity of that enzyme (this is a very simple example). First we need to characterise the proteins crystal structure, then we need to design molecules to inhibit the enzyme, then we need to do a variety of tests both on the drugs effectiveness and clinical trials - that's why the average time it takes to develop a successful drug is about 15 years plus.

So its really too soon to be seeing alot of clinical benefits from the completion of the human genome project, but I'm sure there will be more tangible benefits in 15 - 20 years.--nixie 01:26, 13 January 2006 (UTC)

Special Attack

I don't know if anyone here has seen 'Space cadets' but in episode we see a ex-KGB trainer attempt a move on a cadet. he seems to grab the back of the neck towards the outside end, here he applies pressure and is able to bring the cadet down in a complete nervous bodily loss of control. Is this possible? Are there any articles on it I have no idea what it is called or relates to? How does this work? And how would one attampt to recreate it?

Moreover are similair moves seen in 'Xena' also possible with her attack on the neck which achieves a similair result? (7121989 22:38, 12 January 2006 (UTC))

With enough time and/or strength, you probably could do a Vulcan nerve pinch, but I don't know if it's actually doable in a combat situation. Tzarius 22:47, 12 January 2006 (UTC)
I don't think that actually exists. In fact, I've heard it didn't really exist in the series either, but the article disagrees with me. What exactly is the 'outside end' of a neck? Black Carrot 22:54, 12 January 2006 (UTC)
The 'Outside neck' is purely a fabrication by me but here is my anatomical definition presented by my diagram:

File:Dfdfdf.JPG (7121989 23:04, 12 January 2006 (UTC))

Nice. Well, if he's strong enough, he might be snapping the guy's neck. That's the only non-fictional thing I can think of. Black Carrot 23:29, 12 January 2006 (UTC)
This is likely based on the ability to knock most people out by sudden pressure on the neck in just the right place. If the brain receives a sudden surge of blood, it will tell the heart to stop beating (or slow beating) for a moment. With a perfect blow, you can create a sudden surge of blood, which causes the heart to pause a second, which then causes no blood to go to the brain. Then, the person passes out. In practice, this rarely works. You just end up causing extreme damage to different parts of the neck. --Kainaw 01:49, 13 January 2006 (UTC)
This will better work if you give pressure in front, near the aorta the tendon that mesures the bloodpressure to your brain (can't remember the name of it). You can try this on your self, if you get the right point it immediately affects the bloodpressure (And may cause serious damage to your brain) and you may see nothing for some seconds. My Wing Chun teacher once demonstrated me that. helohe (talk) 17:58, 13 January 2006 (UTC)
Well, don't forget that Space Cadets is entirely made up. Night Gyr 09:09, 14 January 2006 (UTC)

What stops me passing through a wall?

On a minute scale from atoms and up to, sub-atomic particles, quarks and strings what stops a mass of particles pass through another solid? Cos all these particles are essentially energy so something as intangible as energy defines physicality, whats that about? I have though heard of cases where particles are able to transit through each other in quantum physics but the chances are minute of a suitable scenrio fit for such an event to ever occur. (7121989 22:51, 12 January 2006 (UTC))

When you walk into a wall, the normal force that pushes you back is ultimately due to electromagnetic repulsion. Also, note that to go through a wall implies that you need to break apart the wall; a large amount of energy would be required to break apart the strong bond between the particles of the wall. enochlau (talk) 23:12, 12 January 2006 (UTC)
Well I'm no physicist, but I think it's because of the electromagnetic force acting on atoms and molecules - so rather than your particles physically bumping into the wall particles, the electromagnetic repulsion stops your body's atoms from getting any closer to any wall atoms, stopping you. This force applies to everything, so when you think you're standing on the floor, the electromagnetic force means you're actually hovering above it at a minute altitude. I'm not sure if that all makes sense, so anyone else is free to correct me. --Sum0 23:16, 12 January 2006 (UTC)
Well, you're 'hovering' above the ground in the same way that your body is roughly 100% 'empty space'. Solid is as solid does. The forces that make up molecules are what solidness is, and what volume is. Black Carrot 23:26, 12 January 2006 (UTC)

Take two magnets. Move them close together so that they repel each other but do not touch. Photons are the particles that do that and that keep you from going through walls. Each electron is a little magnet. WAS 4.250 04:12, 14 January 2006 (UTC)

what is a tsunamis retreat and rise cycle

See tsunami. --hello, i'm a member | talk to me! 00:02, 13 January 2006 (UTC)

phpbb icons

I am an admin at a forum. Would someone please tell me how to change the generic phpbb icon on top left hand corner? --hello, i'm a member | talk to me! 00:02, 13 January 2006 (UTC)

The easy way... Replace the icon image file on your server with a different image using the same filename. --Kainaw 01:45, 13 January 2006 (UTC)

Liquid Soap Question

Hello, I have a question about liquid soap that has been driving my family crazy! My liquid soap dispenser rests on my sink ledge in both of my bathrooms. However, in one of my bathrooms (the larger of the two) the soap becomes very watery, loosing almost all soap consistancy. It can still lather, yet its like pumping water out of the dispenser. We had some theory about people watering down our soap for some reason, but that is very unlikely. When we fill up the dispenser, the soap is always of regular thickness. After a few days is when it starts to go liquidy. I've recently put tin foil around the dispenser and the problem hasn't occured in a while. The soap brand is Dial. I'd appreciate any insight into this strange phenomenon of soap. M@$+@ Ju 23:18, 12 January 2006 (UTC)

By chance, is the bathroom with the watery soap the same one everyone showers in? Steam is very good at getting into every opening it can find (including the soap dispenser). Then, it becomes water again. --Kainaw 01:44, 13 January 2006 (UTC)
That is a definite possibility. The bathroom does get quite steamy after a shower. I never associated it with the shower because the other bathroom gets steamy as well. I think that you might be right though. Thanks for the info, but one more question. Does the soap loose its cleaning qualities in that state? M@$+@ Ju 21:59, 13 January 2006 (UTC)
It will keep its cleaning qualities. The snappy answer for you is that soap is designed to be mixed with water, so of course it will work when mixed with water. The technical answer is that soap works by isolating non-polar particles in a little sphere of soap particles. The soap particles are nonpolar on one side and polar on the other, allowing the resulting sphere to dissolve in water where the non-polar particle of dirt or whatever would not have. There's a name for all this that currently escapes me. Having the soap pre-dissolved in the water won't change the process. Isomorphic 02:17, 14 January 2006 (UTC)
That makes sense. Thanks alot for your guys' help. M@$+@ Ju 17:38, 14 January 2006 (UTC)

What are two things that are not considered matter?

Could antimatter be one? Dismas| 01:17, 13 January 2006 (UTC)
First, Do your own homework. Second, your teacher may be defining energy as something other than matter. Other teachers claim it is matter in another form (like ice and water being the same thing in a different form). Your notes should tell you what your teacher wants. --Kainaw 01:42, 13 January 2006 (UTC)
Nouns and verbs? Tzarius 04:38, 13 January 2006 (UTC)

I'd say antimatter is actually matter. And Kainaw is right, energy could be considered matter, too. Most nouns refer to material things, and verbs refer to their interactions. To be on the safe side, I'd say space-time and information. --James S. 09:40, 13 January 2006 (UTC)

What about things that don't matter? :) DirkvdM 10:33, 13 January 2006 (UTC)
See abstraction. There are loads of abstract things that are not matter. For example, music, color, knowledge, fashion, philosophy.... --Shantavira 12:28, 13 January 2006 (UTC)
Two such things are money (when it's not cash) and software. – b_jonas 13:14, 13 January 2006 (UTC)
Ah, money is interresting. Essentially it is something immaterial, but it can also be something physical, in the form of a coin or bank note. It's basically information, as is software. But when you put software on a cd you don't say that that is software, merely that it holds it. But when you put money on a piece of paper you call that money too. Is this just words or is there a deeper distinction? (Maybe people would deal with money better if they realised this, but that's another sidetrack.) DirkvdM 07:32, 14 January 2006 (UTC)
The newest book of Mérő László, Az élő pénz, discusses the nature of money. He tries to prove that money is a self-replicating thing. – b_jonas 16:45, 14 January 2006 (UTC)

January 13

Excel

Dear fellow users:

I am wondering if anyone knows how to eliminate the cells in excel which appears when you copy and paste your items onto another program like Microsoft word. I am not very computer technical so if anyone knows, can they please help me. Thank you.

Thank you, Geim

129.97.252.58 00:42, 13 January 2006 (UTC)

If you use Microsoft Word, select "Paste Special" from the menu and then select "Unformatted Text" or "Unformatted Unicode Text". That's it. Or you can paste the selected contents to the Notepad. It will be converted to tab separated plain text. You then copy from Notepad and paste to Word. Have a nice weekend. -- Toytoy 02:26, 13 January 2006 (UTC)

Baryons

There are some baryons missing from the list of baryons. What are they? I now that there's one called Phi (φ). There's a link but my computer can't access the information. Thanks 216.209.153.88 00:54, 13 January 2006 (UTC) Max

The phi particle is not a baryon, but a meson. See list of mesons. —Keenan Pepper 04:24, 13 January 2006 (UTC)

Star Wars in 3D?

From Star Wars:

At a ShoWest convention in 2005, George Lucas demonstrated new technology and stated that he is planning to release all six films in a new 3-D film format, beginning with A New Hope in 2007.

How do they do it? How do they convert an aready been made movie? If they could do that with A New Hope, could they do it with Gone With the Wind? -- Toytoy 02:19, 13 January 2006 (UTC)

Well, he could just re-render the prequels since they were 90% CGI anyway. As for the older 3, he might have a team go over the key frames and put in estimated depth information, then have the other frames interpolated by machine. Or so I speculate, anyway. Tzarius 04:43, 13 January 2006 (UTC)
The Prequels are of much less problem. I bet George Lucas might have taken some principal photography in 3-D already. I want to know if they bother to go some extra miles with the better and more entertaining older movies. If I have unlimited power and resources, I can order people to digitize original bluescreen footages and redo composition from scratch. I can even selectively rebuild some bluescreen elements with 3-D tools (e.g. a closeup shot of the Star Destroyer). Maybe I can even rebuild the set in 3-D. So I can erase the background, and put Luke Skywalker (morphed to create depth cues) and his lovely dad (also morphed) in a virtual Death Star chamber. Maybe they can recreate Carey Fisher, Mark Hamill and Harrison Ford in 3-D as long as they pay top dollars to the actors. Anyway, they can always recreate Darth Vader, Storm Troopers and most robots and space monsters digitally.
I don't think anyone can do the same job easily with Gone With the Wind. The 1939 movie simply does not contain adjustable bluescreen elements.
If I want to do it cheaply, I'll just hire some keyframers and let them do all the lousy morph jobs with cheap computers. -- Toytoy 06:04, 13 January 2006 (UTC)

Wisconsin Weather

Why does Wisconsin get so many cloudy days in January?

During the winter months, cold moist air from the Great Lakes, the Upper Mississippi River Valley, and Canada blows in as cold fronts into warm daytime-heated high pressure zones, accelerating cloud forming and the chance of precipitation.
Why don't you move to New Mexico? Nrcprm2026 09:35, 13 January 2006 (UTC)
Or is it all the gloomy scandnavians? Dalembert 11:05, 13 January 2006 (UTC)

science

The new substance produced in a chemical reaction have the same properties as te original substance?

Well, the products have some of the same properties as the reactants, for example mass, but no, in general the properties will be different. —Keenan Pepper 04:29, 13 January 2006 (UTC)

Alien Lifeforms

What do you think the odds are of Aliens. I mean, the odds have to be really high considering, you need a Rocky planet, the right distance from it's sun, enough water, enough gravity, and enough life sustaining gases.

See the Misplaced Pages article on the Drake equation and related articles such as Rare Earth hypothesis. --JWSchmidt 04:44, 13 January 2006 (UTC)
Depends very much on how you define life. We've only got one planetary environment as an example and even here we keep on discovering things that don't fit in with what we previously didn't think possible. So what could 'life' be like in a completely different environment. Which gases were you thinking of, for example? Oxygen? Well, there are also anaerobic organisms. Right here on Earth. Sunlight? There are ecosystems that get their energy from the Earth at the bottom of the oceans, where there is no sunlight. Just two exmples.
There's life, Jim, but not as we know it. DirkvdM 10:41, 13 January 2006 (UTC)
The short answer is "nobody really knows, and anybody that gives you a confident answer is talking out their backside". --Robert Merkel 14:17, 13 January 2006 (UTC)

Given the enormous size of the universe it makes no sence that we will ever see or hear them although there are probably millions of alian species not knowing from one another.(zh)

exiting earth's atmosphere

my friends and i were having a discusion on wheather or not a United States milatary fighter jet has the structural intergrety and power (propulsion) to make it to outer space. Now we do understand that a fighter yet is not desinged for exiting the earth's atmosphere. let's pertend that we have to put that jet in space. what does it take. i believe a fighter jet does have the structural intergrety to make it and it does have the propulsion as welll. now i believe that because of the lack of oxygen in outer space, the yet would not make it. now i believe (i may be wrong) that if we attached some type of oxygen tanks to the jet so it can be used to burn the fuel, the jet then could make it to outer space. Main question is can the jet itself without any extra addings to the structure of the jet, can it make it then ( remember we are able to only add some type of gas tank to help burn the fuel). the other question is does the earth's atmophere cause the jet to burn on the way out to space.

Take a look at jet engine. A jet engine can't function in space regardless of whether you have oxygen available to burn fuel. The reason is that a jet works by sucking in air, accelerating it, and pushing it out the other direction at a much higher speed. This won't work in space (or in the really high areas of the upper atmosphere) because there isn't enough air to suck in. I believe that scramjets are expected to work higher up in the stratosphere than ordinary jets, but they're still experimental, and no military aircraft are fitted with them. So the short version is no, your jet wouldn't make it to space. Isomorphic 06:16, 13 January 2006 (UTC)
That's quite right. However, replacing the jets with rockets of similar size wouldn't be sufficient either.
You must understand that there is a distinction between getting into space and getting into orbit. Getting into space means only that you must reach an altitude higher than essentially all of the atmosphere. Getting into orbit, on the other hand, requires enough speed that you won't fall back to the ground -- your vehicle will keep circling the Earth -- and for this the minimum speed is about 18,000 mph. (At a still higher speed of about 25,000 mph, it is possible to get away from the Earth altogether and not go into orbit.)
Okay now, 18,000 mph is far beyond anything achievable by a jet airplane. To take a fighter into orbit you would have to modify it so much it would be a totally different vehicle. If that's what you meant, the answer is certainly no.
However, if you really just meant getting into space (after which the plane would drop back into the atmosphere), then the answer is still no, but you might get to a yes by stretching a point.
Looking at various web sites, it appears that the "ceiling" (the highest altitude they can reach in normal use) for of typical fighters is around 50,000 to 55,000 feet, and that's only about 10 miles. To reach 5 times the altitude would require changes so large that again you would be talking about a completely different vehicle. On the other hand, reaching space (not orbit) by an airplane specially designed for the purpose (not a modified fighter), that's been done. The plane was the X-15 and it flew in the 1960s. It was rocket-powered and, to preserve its fuel supply, was dropped from another plane rather than taking off from the ground.
--Anonymous, 06:35 UTC, January 13, 2006
One extra point: Airplanes use wings for lift. Outside the atmosphere, there is no air to create lift. So, the redesign would have to involve turing the airplane into a rocket in mid-flight. --Kainaw 19:54, 13 January 2006 (UTC)
Why do you ask about US military fighters? That is very specific. Did you have something specific in mind? There have, bowever, been attempts at rebuilding an existing Lear jet to get into space. Another thing you might want to look at is SpaceShipOne. DirkvdM 10:46, 13 January 2006 (UTC)

Urgent DVD writer agonies

I'm using a LiteOn DVD-writer; for the last year, it's been perfect. I reinstalled Windows XP last week, and now I'm on the edge of tears because of a major problem: I can't get it to write to the only DVD+Rs I have. I paid for hundreds of these discs, because they've always worked fine with my burner. It writes to DVD+RWs from Nero, but it won't burn to DVD+R. I need it to write these images, but it just won't... it's driving me crazy. I get power calibration errors writing to DVD+R.

Quoting http://forums.afterdawn.com/thread_view.cfm/269363:
"A power calibration error is caused by the inability of a DVD-RW drive to use a DVD-R or DVD-RW disk.
DVD-R and DVD-RW disks themselves have information written on them, within this Media ID code there is information that the drive uses to calibrate itself to the disk, when a drive first starts to write to a disk it will burn a small amount of data to a calibration area on the disc, using the calibration information in the Media ID code, and then try to read back the data that it has written. If it cannot be read, then disk will be ejected and fail with a power calibration error.
A power calibration error is normally caused by problems with the media. Should you be experiencing problems with your drive or the media, we recommend that a disk from a good quality manufacturer be used to test it."
So I guess it's a problem with the discs itself. Sorry, but you might just have spent hundreds on dodgy media. enochlau (talk) 08:57, 13 January 2006 (UTC)

Don't give up yet. Run Windows Update and install everything that looks like it might be a drive patch and try again. Then if it doesn't work you can give up. —James S. 09:02, 13 January 2006 (UTC)

Or switch to Linux? DirkvdM 10:49, 13 January 2006 (UTC)
Well, reading that forum post I quoted above, it doesn't seem like software is the cause. enochlau (talk) 12:37, 13 January 2006 (UTC)

Yeah! I just got my Linux machine to write standard Rockridge data disks, on my standard (cheap) dvd writer, using cheap Costco disks. But I absolutely cannot write a standard dvd that my dvd player can read. I use a direct network connection to the big screen now. --Zeizmic 13:08, 13 January 2006 (UTC)

spinning jenny

hey guys i have a hobby a making any machine that catches my eye then i saw a machine called the spinning jenny i wanted to make a working model of it when igoogled it all i found was about its inventor and even the pictures are from only one angle so can u guys use ur pschic powress and help me by giving me a link or an explanation of its working and how to make it. even the picture that u guys have in ur article of the jenny is different from those in other sites --212.72.18.51 08:57, 13 January 2006 (UTC

I think a "spinning jenny" is a generic name for a compact spinning wheel, of which there are many kinds and variations. Try making a simple spinning wheel first before attempting to woodwork the more intricate compact versions.
Correction: a spinning jenny is apparently multi-spooled with horizontal wheels. That will teach me to try to answer WP:RD questions without RTFA first. I see what you mean about almost all the photos on Google being from the same angle, but a few of them are actual photographs from different angles.James S. 09:22, 13 January 2006 (UTC)
I see your problem. There's nothing on HowStuffWorks, either. I searched Google for -how to make a spinning jenny- and -spinning jenny diagrams-, and the best result I got was this: http://www.austehc.unimelb.edu.au/tia/269_image.html#7 Good luck. Have you tried looking for a book on it? --Black Carrot 12:55, 13 January 2006 (UTC)
A few months back I went to a sheep and wool festival which was basically a big gathering of people at the local fairgrounds who brought their sheep to show off as well as maybe sell some wool that they had made into yarn. At the show there were a number of people selling spinning wheels/jennys. So, what I would suggest is trying to find people who sell hand spun wool, then asking them where to get diagrams and such. There are also message boards on the net for those who are interested in raising livestock. You could ask on one of those. Dismas| 00:43, 14 January 2006 (UTC)
You wouldn't have much luck. As one of those aforementioned wool festival people, I have to say that I don't know anyone that makes spinning jennies or sells plans for one. A spinning jenny is an industrial machine that lead to the end of hand-spun yarn and so is rather the opposite of the ideal of those using spinning wheels. (Of course there are those electric spinning wheels...) Basically the spinning jenny is just a massively multiple spinning wheel. Rmhermen 02:06, 14 January 2006 (UTC)

neurological question

Hello, I would like to know which chemicals (neuro-chemicals) are released from the skin, or the tissue under the skin, when a person is massaged. I know that massage is good for the immune system and other things however I would like to know what happens, chemically, preferably also the route this takes. Hope I have explained it sufficiently - I cannot find anything on the subject! best wishes Anneloes

It's not just under the skin; what a massage does (or so some calim), is to activate the lymphatic system, facilitating its circulation. Mariano(t/c) 13:28, 13 January 2006 (UTC)

Neurotransmitter is a good start. Many pleasurable things act on either the chemicals or receptors. --Zeizmic 13:58, 13 January 2006 (UTC)

Formation of the Patella

Hello! I think I read somewhere that the 'Patella' or bones of the knee joint fuse and take proper form not at birth, but later on, as the human body develops. Is this true? I cannot seem to find this information anywhere at present. Thank you for taking time to answer this question.

Kamalini Mazumder

Hi Kamalini. I found this text -- while it's not specific to the knee joint, it does talk to the issue you're interested in:
The skeleton of a newborn baby is made up of more than 300 parts, most of which are made of cartilage. Over time, most of this cartilage turns into bone, in a process called ossification. As the baby grows, some of its bones fuse together to form bigger bones. By adulthood, your skeleton contains just 206 bones.
--Quasipalm 20:03, 13 January 2006 (UTC)

The patella is cartilaginous in early infancy. The first appearance of bone occurs at 32 to 76 months in boys, and 20 to 40 months in girls. The bones of the knee change size and shape enough throughout childhood that an x-ray of the knee can be used to assess bone age. alteripse 23:48, 13 January 2006 (UTC)

Windows NT Workstation 4.0 Inbound Network Connections Limit, and Existence of Any Such Limit in 2000 and XP

Windows NT Workstation 4.0 was limited to 10 inbound network connections, something about lack of client-access licences. How did this work? How was a connection marked as inbound or outbound? Was the connection per program, per port, or something else? Could this be changed in the Registry? Do any such limits exist in Windows 2000 or XP? Thanks.

MSTCrow 13:50, 13 January 2006 (UTC)
This is probably too specialized for this forum. I know from my own personal nightmares that Windows networking carries a lot of baggage from the early days. They were competing with Novell at the time, so there is the issue of a sever/client list being constructed and replicated on each individual machine. This became a big mess with many servers, so Win NT may have limited things. Bottom line is that we can't help you. --Zeizmic 17:54, 13 January 2006 (UTC)

search engines

What is "offline searching" ? searching offline!!!--212.72.15.118 14:40, 13 January 2006 (UTC)

This is a good question that passes the preamble test. The term is probably marketing buzz. Computer searching used to be always 'offline' because nobody was on the Internet (long time ago!). Think of the 'Find' command in Windows. Then came the big Internet search engines (Google was not the first!), with all sorts of different algorithms to improve the search process. Now, these algorithms are being applied to either files on your PC, or inside a corporation. Our company just started with a new one with mixed success, since it is difficult to use the Google method of link-rating on this internal cruft. --Zeizmic 16:08, 13 January 2006 (UTC)
It may mean "searching your PC" (as Google Desktop Search does) or "searching your intranet" (as a Google search appliance does). But as Zeizmic says, it's likely a marketing term that hasn't achieved enough currency to mean a specific thing, if anything. -- Finlay McWalter | Talk 01:06, 14 January 2006 (UTC)

how can i loose weight

i am 106 Kg but my weight is 172 cm,,, and i am over wieght and i love eating what can i do to loose weight and not stop eating? there is only one word for the answer--212.72.15.118 14:38, 13 January 2006 (UTC)

You have two options:
  1. Increase the amount of calories you burn (exercise).
  2. Decrease the amoung ot calories you eat (diet).
--Quasipalm 19:59, 13 January 2006 (UTC)
As to strategies to help you achieve those things, there are well-known services that provide calorie-controlled food (such as Weight Watchers and Jenny Craig; anecdotally, I've heard that those services tend to help you lose weight but people tend to put much of it back on again); there are also certain drugs available on prescription from your doctor that can help control your appetite in various ways. For exercise, if you can afford it you might consult a personal trainer or sign up for aerobics classes if you find exercising by yourself unsatisfactory. But there's no magic solution. If there was, I'd be considerably lighter than I presently am. --Robert Merkel 00:17, 14 January 2006 (UTC)

Just Eat better and Exercise dude, i lost 116 lbs in 5 months.

If you're really desperate, you could try hormone treatment, but it's not a large problem it seems yet unless it escalates further, but you should just see your doctor if you're worried about anything. If it's just genes and metabolism, your doctor would probably be able to aid you in something (ie. give you mild stimulants). Elle vécut heureuse (Be eudaimonic!) 04:20, 14 January 2006 (UTC)
You say you love eating. Do you like food or do you like stuffing your face? Maybe a change from junkfood to tasty food could help. Alternatively, start smoking. :) DirkvdM 07:48, 14 January 2006 (UTC)
I second that. Smoking less than 10 cigarettes a day helped me to lose a lot of weight. Granted, now I smoke, but I look better. I think it can be safely argued that the net change in my lifestyle as a result of smoking has led to increased health. And quitting smoking is a lot easier for me than losing weight any other way. On a side note, diet can definitely help you lose weight; but if your goal is also to look good, then you will need to exercise. I only dieted, which led to me looking great fully-clothed, but less than super whilst nude. Any way of changing your weight is going to have a profound impact on your lifestyle, so I urge you to examine your motives before you begin any one path. The worst thing that can happen is not just that you won't lose weight, but that failing to do so will cause you to give up trying. It's important to stay realistic with yourself. Bethefawn 04:47, 15 January 2006 (UTC)

comp problem

i keep on getting this error "about some weird thing called "kernel 32"any hints on what it is and how i can remove or treat it--212.72.15.118 14:15, 13 January 2006 (UTC)

The thing about error messages is that they might look like rubbish, but they often contains details that matter. Also, there are so many possible messages that just picking one word could be about anything. There is a very important file in windows with Kernel32 in the name. I recommend you post the exact error message, word for word, and details of what you are doing when it happens. Notinasnaid 16:30, 13 January 2006 (UTC)
And mentioning the OS would also help. DirkvdM 07:48, 14 January 2006 (UTC)

i use windows 98 it happens when i switch on my comp any program that i open is closed due 2 it

Size

How to increase the size of penis

take a a bowl filled with spaghetti and pour some sauce(soy preffered).add some valium and swirl a drink in a gulp for better results take one gran of the metal penisenlargium--212.72.15.118 15:26, 13 January 2006 (UTC)
More seriously, see penis enlargement. There are many methods; in general, they:
  • don't work, or
  • do work, but have serious side effects, or
  • don't work and have serious side effects
Then there's the MAKE PENIS FAST!!! method. . . :) Mirv 16:10, 13 January 2006 (UTC)
Simple fact of life... If there was a method of penis enlargment that worked without serious side effects, nobody would be asking about penis enlargment. --Kainaw 01:20, 14 January 2006 (UTC)

Watch some hard-core porn, that should increase the size dramatically in just seconds. StuRat 06:50, 14 January 2006 (UTC)

Human Genome Project

Following the question asked yesterday I started thinking. Their stated goal in the Human genome project was to map the genes in a human body. So whose genes did they map? Presumably they mapped the genes from one individual as if they had used genes from more than one individual they may have missed some (say a gene that is present in Chinese but not Causasians, etc). So does anyone know? AllanHainey 16:38, 13 January 2006 (UTC)

Someone asked Celera bigwig Craig Venter who they were, and I believe he said there were seven or eight people used, with a range of "races". He confirmed that one of the "caucasians" was himself. I believe the HGP did much the same thing. -- Finlay McWalter | Talk 17:37, 13 January 2006 (UTC)
  • You might be interested in this FAQ from one of the National Labs invoved in the US govt effort. Basically, the explanation they give is that they took samples from a large number of people, then mixed a few of them together, so that no one who donated a sample can be sure if any of there genetic material was used or not. That source also confirms that Venter's DNA was among that used in the private effort. This source provides a similar, but slightly different answer. You might also want to keep in mind that this project is never "done" in the sense that additional sequencing of additional people continues. The additional sequencing helps identify variations, links between variations and diseases, etc. Johntex\ 03:03, 14 January 2006 (UTC)

Microsoft XP Controversies

Did microsoft lose sales of windows XP due to the activation thing and will it be included in Windows Vista? Additionally, will just having an AMD Athlon 64-bit processor will be enough to be able to get the Windows Vista 64-bit version? Finally, how well does WOW64 work (for those who have the preview edition or Windows XP x64)? Ilyanep (Talk) 17:08, 13 January 2006 (UTC)

This is politics, not science. Read the thing at the beginning. Sorry. --Zeizmic 20:58, 13 January 2006 (UTC)
Oh, sorry. I was thinking Computer Science (because of the latter part of the question). Ilyanep 23:35, 13 January 2006 (UTC)
For the second question, the 64-bit versions of Windows will run on an Athlon 64 so long as you have adequate memory and disk space, and compatible hardware. By compatible hardware I mean a normal PC, not something with an incompatible BIOS or video card, for example.
I understand the current 64-bit XP doesn't run existing 32-bit Windows software at all well, but I don't know to what extent this problem may have been overcome in 64-bit Vista. This is just my impression, I have never actually run 64-bit Windows.-gadfium 02:37, 14 January 2006 (UTC)

Pendulum

Can any body refer me to links/resources that explain how pendulum is used in alternative medicine. I want to know how pendulum can be used to diagnose and treat a disease. I know there is an article about pendulum in Misplaced Pages but it does not tell what i want to know. Thanks a lot

Have you also read the article on alternative medicine? And personally, I'd suggest pseudoscience. Dismas| 00:35, 14 January 2006 (UTC)
I seem to recall an old wives tale about using a pendulum to determine the gender of an unborn baby. StuRat 06:46, 14 January 2006 (UTC)
It's called radiesthesia. --Shantavira 12:08, 14 January 2006 (UTC)

LCD Vs CRT

I use the computer monitor mostly for reading only. I just want to know which monitor is best for using it for reading- CRT? or LCD? All these days I thought LCD was better, but I read in a magazine yesterdaythat CRTs are better and one of the reasons for that is CRTs have less glare. Is it true? Finally, which do you think is the better?

If anything I would've thought that LCDs have less glare since there isn't that piece of glass at the front to reflect light off. I personally find LCDs much sharper when reading text. enochlau (talk) 01:13, 14 January 2006 (UTC)
With an LCD, you get: Less glare, straighter lines, and more contrast between colors.
With a CRT, you get: Possibility of a brighter image, a wider range of screen resolutions.
The problem with the CRT is that a cheap one will commonly have a curved and blurry image compared to a cheap LCD. However, an expensive CRT will have a picture that is possibly better than an expensive LCD. --Kainaw 01:18, 14 January 2006 (UTC)
They are both fine, but many people do not know how, do not care, or do not choose to adjust them for optimimum confort when reading. Often, monitors are too bright, and reading black on white for a prolonged period is uncomfortable. In my opinion, this sends people off on many wild goose chases, like seeking to change to white on black, rather than fixing the monitor. Notinasnaid

Internet through satellite phone

Some companies offer 2.4 kbps and 10 kbps Internet access via satellite phones which can be connected to a PC for browsing. How much does a 2.4 kbps unlimited and 10 kbps unlimited Internet plan cost per month? I was not able to find this in Iridium's website.

I don't think they sell the service directly themselves. http://www.satphonestore.com/servprod/iridium/ sells phones and service packages. Their price for 1000 prepaid minutes (note that's not minutes-per-month, that's use-once and gone forever minutes) is $990.00 USD. So a full month's worth of continual connectivity would, at that rate, come in at over $42,000 USD. Cheap, huh? -- Finlay McWalter | Talk 23:12, 13 January 2006 (UTC)
I'm fairly certain that if you email or call Iridium, they could give you plenty of information about their pricing structures. Dismas| 23:45, 13 January 2006 (UTC)

McDonalds accounting sales figures

How does McDonalds do accounting? If I eat a burger which costs $2, will $2 add up in the sales figures of McDonalds or will only royalty got by McDonalds from store franchisee add to McDonald's sales figures?

If royalty is 10% of sales and cost of burger $2, then, will $2 or $0.2 add to its sales?

In this case "sales figures" can mean two things: a figure used for publicity (pertaining to the whole McDonalds "family") and a strict incomine figure, reported in a government filing. The former is an informal thing, something they might put into a press release; how they calculate this is up to them. The latter is an actual reflection of the real income received by the parent McDonald's company, and is calculated according to strict accounting rules set out by the government (and sometimes the market). In this case the turnover of the franchisees won't be reported. So you might read "in 2004 McDonalds restaurants sold 500 million burgers for 1.2 Billion US dollars, and McDonalds corporation reported turnover of 211 million dollars". -- Finlay McWalter | Talk 01:03, 14 January 2006 (UTC)

Endorphins

I know that working out at night can keep you up late at night due to the Endorphins keeping you up. I was just wondering, how long do the endorphins effect your body for to keep you awake?

I don't have a good source on this, but I remember that endorphins clear in a matter of minutes; the half-time is probably 5 or 10 minutes. However, everything in metabolism is interrelated, so your wakefulness has a lot to do with blood sugar, the amount of protien versus carbohydrates in your gut, how much sleep you've been getting, how much caffiene, alchohol, and other drugs you've had, etc. But from experience, if you break a sweat every half hour, it helps to stay up until a critical point when working out just makes you more tired. --James S. 07:23, 14 January 2006 (UTC)

January 14

Firefox tabs problem

I use Windows XP (sorry :)), and I seem to have an annoying problem when opening new tabs in Firefox. Sometimes, when I open a new tab, the whole Firefox window "restores" from its maximised state to that "restored" state where you can drag the window around. I then have to maximise it again. This doesn't happen very often, but it usually happens when I open a new tab just after Firefox starts up or when an external application opens a webpage in a new tab. Any suggestions on how to fix it? -- Daverocks 01:47, 14 January 2006 (UTC)

Not really a Science ref desk question, but anyway, it may be the pages you're opening have Javascript code to resize the window. You can prevent this by going to Tools > Options > Content > Enable Javascript (Advanced) > and untick the "allow window resize option". Tzarius 06:10, 14 January 2006 (UTC)
You'd think that (and I do know some pages which have JavaScript that resizes), but the problem occurs even when I press Ctrl+T to open a new tab consisting of a blank page. I don't think there's any JavaScript code on a blank page. :P
Also, I have seen many computing-related questions on the Science ref desk. It even says on WP:RD that the Science ref desk is "To ask questions about science, medicine, computing, and technology". -- Daverocks 07:13, 14 January 2006 (UTC)

Stars lifespan

The stars are big balls of gases (helium, I guess). Being so, why does it take billions of years to burn (fusion) all that gas, thus making a star extinct, in stead of burning it all at once, as when we light a fire next to a balloon full of inflamable gas, making it explode? Thanks for any help.--201.28.77.123 01:50, 14 January 2006 (UTC)

Firstly, a typical star is full of hydrogen, not helium. Although it may seem as though your balloon explodes "instantaneously", it just appears so because the volume is so small. A star, being much bigger, takes a longer time to go through its fuel. enochlau (talk) 01:52, 14 January 2006 (UTC)
That's not really an explanation, though. We need to understand why the whole ball of hydrogen doesn't all go into fusion pretty much at once. There has to be a process which prevents this, keeping the star roughly at equilibrium (with only a tiny proportion of its hydrogen being fused at any time). I don't know, so I did some digging around. Our nuclear fusion and stellar nucleosynthesis articles don't really explain this mechanism but Image:Nucleosynthesis in a star.gif says "nuclear burning occurs at the boundaries between zones". Star says "A variety of different nuclear fusion reactions take place inside the cores of stars, depending upon their mass and composition". So I think this means that the heat inside the star isn't enough to cause fusion, and that the pressure due to gravity is needed too. If that's the case, you'd expect a fairly thin hollow spherical shell deep within the star to be the locus of fusion - above that shell the pressure (I dunno if "pressure" is really the exactly right word here, but you get the idea) is too low to cause fusion. Below that layer the material must already have undergone fusion. Thus (if this handwavery conjecture is right) the mechanism that slows fusion to a steady rate is that only so much hydrogen is available at the fusile pressure zone, and that the rate of transport of fresh fuel down to that layer is limited by the viscocity of the plasma. So, if this is correct, you'd expect a young star to be laying down a roughly spherical helium core, with fusion occuring only at the boundary sphere between it and the hydrogen. As far as I can tell, we don't have an article that explains this (and I have to stress this is me thinking out loud, not an answer at all) - we really should have one. -- Finlay McWalter | Talk 02:14, 14 January 2006 (UTC)
If you're asking why it doesn't actually catch on fire, that's simple. There's no oxygen. Superm401 | Talk 04:15, 14 January 2006 (UTC)

Gravity causes matter (mostly hydrogen) from space to gather together. Momentum causes stuff to circle each other rather than all go staight away into one big clump. Over time clumps get bigger due to gravity. Eventually some clumps of mater get big enough that the pressure at the center causes fusion. The fusion creates energy that counteracts the gravity. The size of the star is all about the balancing act between the force of gravity and the force of the energy created by the fusion. More matter in the star produced more gravity causing more fusion creating more energy thus balancing the more mass. When the balancing act is disrupted by something the star can colapse or explode. WAS 4.250 04:30, 14 January 2006 (UTC)

To clarify, this energy causes the star to expand (because hot gases vibrate and force each other away). This retards nuclear fusion, as the further apart the atomic nuclei are, the less often these nuclei will strike each other and fuse. StuRat 06:37, 14 January 2006 (UTC)
In other words, there is an incredibly small chance that an atom will hit another one exactly the right way (head on with the right speed) to cause the two to fuse. It's just that there are so damn many that so much energy is produced. But it will take a long time for all atoms to have hit another one just the right way. DirkvdM 08:07, 14 January 2006 (UTC)

1800

Hi, What was the background of quantum mechanics that dates to 1800? and with what equipment could they possibly study it back then? thanx. :) --Cosmic girl 02:04, 14 January 2006 (UTC)

I think you are refering to the particle/wave duality of light. See Double-slit experiment for more information. —Ruud 02:09, 14 January 2006 (UTC)

thank u :) --Cosmic girl 02:51, 14 January 2006 (UTC)

Or see wave-particle duality. StuRat 03:17, 14 January 2006 (UTC)
The very first idea of quantum mechanics was given in a lecture in December 1900 by Max Planck on his idea for explaining the black body radiation law, by quantizing the allowed energies of the oscillators. Of course reality itself has been quantum mechanical since the Creation. GangofOne 16:11, 14 January 2006 (UTC)

Claims of Scientific Evidence Against Evolution

In your website, you talked about scientific evidence for evolution.But then, how come I've heard Christians and creationists claim that there are scientific evidences against it? I'm confused! How can there both be evidence for evolution(or any other theory) and against it?

Exactly what are these claimed-to-be evidences against evolution and are they really evidences against it? Can you please make an article about these claims of scientific evidence against evolution?

You would be interested in creation science and intelligent design. Superm401 | Talk 04:18, 14 January 2006 (UTC)
Easy, they don't know what they're talking about. There is plenty of evidence for evolution. "Evidence against it" is a stupid and terribly misleading way to put certain gaps on our knowledge, which is entirely alright. Besides, I wouldn't listen to these people: they don't need "scientific evidences" to believe in their God, so they should just keep their mouth shut on this whole "scientific evidence" subject. ☢ Ҡieff 04:19, 14 January 2006 (UTC)

One can find evidence for and against almost anything. For example the Flat Earth Society collected all kinds of peculiar and isolated "facts" they would claim as evidence against a round earth. Likewise if your a priori commitment is against evolution you can find some "evidence" against it. The latest fashionable evidence (now termed irreducible complexity) is a re-tread of William Paley's 19th century observation that the eye is really complicated and he just couldn't imagine any stepwise development of the eye; likewise Michael Behe just can't imagine that various complex molecular systems could have developed in steps. The other major "evidence" cited against evolution is that we don't have fossils of many intermediate forms of animal that would seem to have been in a lineage (we have many but not all). We have many articles on the controversy (see all the articles linked to evolution, creationism, and intelligent design). Despite these pieces of evidence, unless you have a prior faith commitment to the late 19th creationist scenario, the more you learn about biology the more it becomes overwhelmingly obvious that evolution in some form has certainly been occurring for millions of years, that all forms of life on this planet share a genetic ancestry, and that there a zillion pieces of evidence supporting it for every one that someone claims opposes it. alteripse 04:29, 14 January 2006 (UTC)

Because they lie to save souls. See Kitzmiller v. Dover Area School District. On 20 December 2005, Judge Jones found for the plaintiff and issued Wikisource:Kitzmiller v. Dover Area School District et. al. in which he wrote:

"Throughout the trial and in various submissions to the Court, Defendants vigorously argue that the reading of the statement is not “teaching” ID but instead is merely “making students aware of it.” In fact, one consistency among the Dover School Board members’ testimony, which was marked by selective memories and outright lies under oath, as will be discussed in more detail below, is that they did not think they needed to be knowledgeable about ID because it was not being taught to the students. We disagree." (footnote 7 on page 46) - WAS 4.250 04:41, 14 January 2006 (UTC)
  • I can't imagine how X could occur naturally
  • In fact, no one can imagine how X could possibly occur naturally
  • Therefore it is impossible for X to occur naturally
  • Therefore it must have came about by supernatural means
  • Therefore God/Allah exists and have create X
  • X of course is "earthquakes in the 18th century"
  • It is a fact that no one in the 18th century could imagine how X could possibly occur naturally
  • Therefore God/Allah must have existed in the 18th century

Ohanian 10:33, 14 January 2006 (UTC)

To answer you quite plainly, there is no evidence against evolution, it is an undisputed fact of nature. There is still debate over the precise nature of evolution, its historical trajectories, etc. but no one takes seriously the idea that evolution does not occur. Creationist arguments are based on religious beliefs and have no ground in reality. --Tothebarricades 11:58, 14 January 2006 (UTC)

Probably the best listing of such things: An Index of Creationist Claims (With a rebuttal for each.)--Fangz 18:55, 14 January 2006 (UTC)

The Rate of Global Warming

I've heard some scientists say that it is likely that global warming is occurring much more quickly than most scientists had originally thought.They say that many things scientists predict global warming will cause by the year 2050 will actually occur much more earlier, by only ten to fifteen years later.Excatly why and what's the reason they believe this?

This smells like homework, but you should read the preamble to this forum. --Zeizmic 04:20, 14 January 2006 (UTC)

Read these. The first one includes:

Today, the alarm bells are being sounded by scientists themselves. In a meeting in Brooklin, Canada, last month, they revealed the following: 2005 was the hottest year in modern times; the impact of climate change was coming faster than expected; satellite photos show there is 20 percent less Arctic ice today than in 1978, a speed of melting unprecedented in history ("the Arctic is a major driver for the earth's weather cycle"); a study shows over half of the northern hemisphere's permafrost would melt by 2050, unleashing billions of tons of methane, a greenhouse gas more potent than carbon dioxide, which would dramatically accelerate global warming; Greenland lost 162 cubic kilometers of ice each year from 2002 to 2005, higher than all previous estimates, contributing to rising sea levels; and so on. WAS 4.250 04:53, 14 January 2006 (UTC)

Draw a circuit diagram for a frequency generator unit

The efficiency of solar cell

That information is available at Solar cell (in fact in several different places in that article...). —Keenan Pepper 06:03, 14 January 2006 (UTC)
The current technology is extremely inefficient. Passive solar energy, like heating a house via windows, is far more efficient. StuRat 06:11, 14 January 2006 (UTC)
Yeah, that's an example of how our attitude towards our surroundings has changed. People used to look at the lie of the land and build their houses accordingly (ie on a sunny southern slope in a cold climate). Our powerful technology has made us so cocky that we think we can stuff our will down nature's throat. Which is true to some extent, but it comes at a price. Such as overconsumption of energy. DirkvdM 08:18, 14 January 2006 (UTC)

Need to urinate after drinking

After drinking quite a bit, I find I need to urinate. What's strange is that shortly thereafter, I get this constant urge to urinate, no matter how often I go to the bathroom. It's like an uncomfortable feeling, like I need to pee, but doesn't go away even after I do my business. Any ideas what causes this? --24.231.16.6 05:56, 14 January 2006 (UTC)

Frequent urination after consumption of alcoholic beverages is quite normal; the ethanol suppresses the pituitary gland's production of the hormone vasopressin. Vasopressin triggers the kidneys to concentrate urine and retain water in the body; in its absence urine is much more dilute and has greater volume. It's possible that the reduced vasopressin concentration in the blood also triggers a psychological need to pee, but I'm speculating at this point. (Vasopressin has been implicated in certain aspects of memory formation, and the closely related compound oxytocin is definitely psychoactive.) TenOfAllTrades(talk) 06:02, 14 January 2006 (UTC)
I appreciate that. Maybe I can add another idea (though this is speculation also). I understand that one of the symptoms of a diabetic is the desire to drink more water and the urge to urinate more. Maybe an excessive consumption of alcohol leads to a higher blood sugar level. I'm 230lbs, 6'2", my ideal weight, I believe I'm about 40lbs overweight. Could this be somehow related? In any case, even directly after urination I still get the uncomfortable feeling that I need to conduct my business with nature. Could this be linked with the excess sugar level (if my speculation is correct)? --24.231.16.6 06:21, 14 January 2006 (UTC)
Yea, that speculation sounds reasonable to me. Alcohol is quickly metabolized into blood sugar by the body. An overweight heavy drinker is quite susceptible to diabetes. You should have your blood glucose level checked. StuRat 06:56, 14 January 2006 (UTC)
My friends and I refer to this as "breaking the seal". Once you urinate the first time, you have to keep getting back up to visit the bathroom again. Dismas| 13:50, 14 January 2006 (UTC)
I've noticed when I really have to urinate badly, that after I go, a few minutes later, I have to go again, with perhaps 1/3 the original volume. I attribute this to urine "backing up" into the kidneys, although the term "backing up" isn't quite right, since the urine does go backwards, it just fails to move to the bladder. StuRat 14:01, 14 January 2006 (UTC)

The frequent urge to urinate can also be a sign of some type of urinary tract obstruction-- for example, Benign prostatic hyperplasia, prostatitis, neurogenic bladder, or other functional derangement of the urethral sphincter. This often manifests as urinary retention, or the sense that the bladder retains residual urine after urination.--Mark Bornfeld DDS 15:30, 14 January 2006 (UTC)

mountains are cold

We know mountains are cold and kavir (salty desret) is hot. why?

Altitude and rainfall. Night Gyr 08:56, 14 January 2006 (UTC)

homosexuals

can homosexuals be treated through psychiatry???

If a homosexual has mental health problems, psychiatry might be helpful. The same is true for heterosexuals, by the way. David Sneek 09:23, 14 January 2006 (UTC)
I think the question presupposes that homosexuality is a mental condition that needs to be treated. It is a perfectly normal way of being for a significant proportion of humans, and is not any kind of condition. The question is based on a false premise. JackofOz 09:32, 14 January 2006 (UTC)

Ask yourself if your heterosexuality can be "cured" thru psychiatry ... then you will know how homosexuals feel when they hear such a suggestion. StuRat 09:58, 14 January 2006 (UTC)

Homosexuality is not considered a disorder, and most people would be offended by the suggestion. There are places where far-right religious groups attempt to do this, but it basically amounts to psychological torture. The Nazis spearheaded similar efforts. The result is usually the creation real psychological disorder (for obvious reasons) or at least personal trauma of some kind, not a change in the person's sexual orientation. --Tothebarricades 11:53, 14 January 2006 (UTC)

The answers are certainly politically correct, but not entirely factually correct. There are people with homosexual orientation who have sought treatment to change it and there are doctors who have sought to help them. Treatments in recent decades in Western society have been voluntary not involuntary and have not involved anything that would commonly be considered "torture" (i.e., no involuntary unpleasantness to the body). The success rates for these treatments do not seem to be large and "relapse" (for lack of a better word) is reportedly common. The arguments above that (1) homosexuality is not a disease, (2) one should not attempt to change this orientation for oneself, and (3) that it would be unethical to attempt to help someone change his/her orientation reflect a reaction to historical social mistreatment of people with homosexual orientation, are political attitudes which should not be presented as "facts", and are in logical contradiction to the general social POV that humans shuould be able to own and develop their own sense of sexuality found throughout Misplaced Pages and educated western society. This is exactly what political correctness is: socially enforced maintenance of a single political viewpoint on an issue for which more general ethical principles would allow a different or more than one opinion. Those who feel compelled to rebut, please address what is said here rather than supplying me with opinions I do not hold. alteripse 14:42, 14 January 2006 (UTC)

  • Well said! And you actually used political correctness correctly, which is as rare as an original simile. --jpgordon∇∆∇∆ 17:08, 14 January 2006 (UTC)
    Huh? The way I read the political correctness article intro, it seems he used the term incorrectly and redefined in a way that supports his personal viewpoint of political correctness (although perhaps unintentionally). According to it, the term "political correctness" usually applies to language ("firefighter"/"fireman") and not really to things like whether homosexuality is a disease (which falls within how Alteripse defines it). The way Alteripse uses the term, he is including (liberal) political viewpoint in his generalization of "political correctness" - not that it's "wrong" (it's his POV), but that's not really factual since the term usually doesn't include anything about something so non-lingual as whether homosexuality is a disease.
    In either case, though, the debate over what is "political correctness" doesn't belong here - the more important thing I wanted to note is that a question like this will attract lots of POVs, and everything should be taken as opinion whether it is stated with "I think"s or not. --AySz88^-^ 05:10, 15 January 2006 (UTC)
Good point, AySz88, about everything here being opinion. However, political correctness does include ideas that have been deemed to be "inappropriate". Depending on whom you ask, this might include a belief in white supremecy, speaking against immigration, men oppening doors for women, wishing people a "Merry Christmas", saying that one doubts that many top femal golphers could beat a top male golpher, pointing out that in order for some kids to be "above average" there must be other kids that are "below average", or any other idea that is deemed to be potentially offensive to a group of people. Johntex\ 05:20, 15 January 2006 (UTC)
This is a topic of some debate. The overwhelming consensus of the psychiatric community is that 1) changing sexual orientation is either exceedingly difficult or, more likely, impossible, but 2) that's fine, because no sexual orientation needs treatment anyway - it is society's oppressive views that need changing. A very few professionals disagree with this opinion in one way or another. Some believe that people should be allowed to seek therapy to change their sexual orientation if they choose because it might work, while a very few believe that non-heterosexuality is a problem per se and so should be treated. (This view, however, is much more common among people who aren't mental health professionals and particularly among people who have religious reasons for disapproving of homosexuals.)
Research on changin sexual orientation has been done for years, though it is very uncommon these days for the reasons mentioned above. Unfortunately, most of the research is of a rather low quality; further, there has been no research that I'm aware of on converting htereosexuals to homosexuality, so it's hard to give a definitive answer to your question. Suffice to say that it seems that a few people can change, but probably not the overwhelming majority of people. --George 20:53, 14 January 2006 (UTC)
  • I'd like to add a note about how and why various psychological conditions become "disorders" or "diseases" (or have such classifications taken away, as in the case of homosexuality) in the field of medicine. The main reasons are usually bureaucratic rather than political. The way modern medicine works is that every medical condition, procedure, problem, disorder, etc., must have a code. Without said code, insurance companies (and/or the government) will not pay the doctor's or hospital's bills. Thus, every time a new edition of the standard manual of psychological disorders is published, it is much larger than the last (as are the manuals for all other fields of medicine), because it's the only way psychiatrists, psychologists, therapists, and other health professionals can get paid for the latest and greatest treatments. As a result, there is tremendous pressure on the commitees responsible for such manuals to accept almost every newly coined term in medicine, regardless of how many people actually may qualify as having any such new given condition, or even whether it's been generally accepted throughout the entire medical commitee. In short, it's a very, very political process, and always has been. Usually the politics are driven by business interests, but sometimes they're politics of a far more ideological nature, which is what happened in the case of homosexuality being dropped from the DSM-IV. Does the fact that homosexuality was removed from the DSM-IV truly mean that homosexuality is unquestionably not a mental disorder (in the purely clinical sense of "not being the norm")? Or that it unquestionably is? Not at all. Even now, in the early 21st century, we know very little about the way the brain works, and even less as to what truly causes a given person to grow up to self-identify as belonging to a particular sexual orientation. It s entirely possible that, at some point in the future, someone will come up with some sort of gene therapy that will cause all humans to whom it is given to lose all homosexual urges. Likewise, someone could come up with a therapy to make all humans gain homosexual urges. Maybe it will never happen. We just don't know. And these possibilities will remain no matter what the psychological establishment deems to be The One Truth on this, or any other, psychological issue. --Aaron 04:16, 15 January 2006 (UTC)
  • Another very informative answer! What is a "disorder" is somewhat in the eyes of the beholder. Overeating, smoking, and flying on the space shuttle are all unhealthy in the sense that they reduce one's life expectancy, statistially speaking. There are certainly clinical efforts to help people quit smoking and overeating - not sure about the shuttle. :-) Should they all be considered disorders? Johntex\ 04:49, 15 January 2006 (UTC)

As a person who does not discriminate by gender, I take great exception to Alteripse's implication that "homosexuality is not a disease" is a political stance. There is far more evidence that homosexuality is a natural phenomenon than a disease/disorder. To "wait for findings", as it were, would be like questioning the holocaust because you've never visited Germany. It has far reaching social, not political, consequences. I know what you are proposing doesn't necessarily imply homophobia, but it fosters it terribly.the preceding unsigned comment is by Bethefawn (talk • contribs) 22:44, 14 January 2006 (UTC)

computer science projects

what kind of process power is used for artificial intelligence? please explain

from julie

thank you, ps i need this asap

Your question is far too generalized. Most video games have AI in them now. The bad guys you run around and shoot are operating on AI. Also, there are very small AI devices that do things like judge if someone has entered a room and then turn on the security camera. If you are looking to re-create a human brain with electronics, you'll have to wait about 15 years and be very rich or wait another 30 and buy a basic home PC. --Kainaw 14:34, 14 January 2006 (UTC)
Ugh. I hate this watered-down use of the term AI to refer to things that could never pass even the simplest Turing test. We don't have actual artificial intelligence (machines that can think and learn as we do) yet, and it will probably be a long time before we do. —Keenan Pepper 23:39, 14 January 2006 (UTC)
Years ago, after an AI class in college, I suggested that the big problem in creating artificial intelligence is that nobody really knows what intelligence is. On ther other hand, everybody knows what stupid is! So let's start first with artificial stupidity. To my great surprise, that's kinda what happened: expert systems are artificial stupidity! --jpgordon∇∆∇∆ 04:57, 15 January 2006 (UTC)

Twistors?

I'm reading a book on string theory but its slightly outdated. There are several chapters on twistors, and I'm wondering if the notion that the concept of the twistor may aid the quest for a theory of everything is still taken seriously in the scientific community. Because I don't want to waste my time otherwise. --Tothebarricades 11:56, 14 January 2006 (UTC)

I can offer only a partial answer (due to my own knowledge limitations). Depends on which scientist you ask. Roger Penrose who came up with twistors still likes them, but he seems to admit that they are not on the mainstream, see his book The Road to Reality. However, you must decide why you ask-- Do you wish to be expert on what others think? or do you seek the truth? Since fundamentally NOBODY knows what the right answer is, nobody knows if twistors will be part of the RIGHT TOE of the future. So nobody knows if it's a waste of time. GangofOne 15:48, 14 January 2006 (UTC)

Methamatical brain

I have been asked to prepare a methamatical model of brain can u help me by telling me how to prepare it?

Could you be more specific? And, if this is school homework, we really aren't supposed to do it for you. But help I guess is fine. --Tothebarricades 12:01, 14 January 2006 (UTC)
Good preparation would be get PhDs in Math, Computer Science, and neuroscience. Then read On Intelligence by Jeff Hawkins, Sandra Blakeslee ISBN 0805074562 . They seem to have some new insights on just this problem. GangofOne 16:03, 14 January 2006 (UTC)

mass media

is cellphone a mass media?

I believe this was already asked and answered. StuRat 13:54, 14 January 2006 (UTC)
Here it is. David Sneek 17:04, 14 January 2006 (UTC)

Volcanos

Is there any sort of connection between Mount St. Helens and Augustine Volcano? The reason I ask is because of the recent activity at MSH and now in the last few days there have been eruptions at AV. Are they connected to the same "vein" of lava or anything like that? I mean, I know that the center of the Earth is liquid but am unfamiliar with the interconnectivity of volcanos if any exists. Dismas| 13:56, 14 January 2006 (UTC)

They are both near the boundary of the Juan de Fuca Plate. Plate movement influences seismic activity, which in turn is believed to influence volcanic activity. To claim that the Juan de Fuca plate is influencing them, you would have to show an increase in activity of some sort along the plate and then show that that activity has increased volcanic activity in the past. --Kainaw 19:43, 14 January 2006 (UTC)

i have AMD sempron 64-bit processor(2500+) to install xp 64-bit or not

i have AMD sempron 64-bit processor(2500+) my doubt is weather to install windows xp 64-bit or to install windows xp 32-bit

system configuration AMD sempron 64-bit processor(2500+) 1400 MHz L2 CACHE: 256 kb L1 CACHE: 64 kb 256 MB DDR 400 MHz RAM ASUS TEK K8V-MX MOTHER BOARD 40 GB SEGATE 7200 RPM HARD DISK


IF I WAS ABLE TO INSTALL WINDOWS XP X64 DOES IT SUPPORT MY 32-BIT APPLICATIONS,

PLESE SAY SOME THING...


You could install Windows x64 and it should supposedly run faster, but the problem is that many consumer applications aren't written to support 64-bit natively. It will support your 32-bit applications, because of WOW64, but I don't know how stable it is. You may see a slight performance boost, but personally I am waiting for Windows Vista to come out until I get a 64-bit OS, and I'm running an AMD Athlon 64 3200+ — Ilyanep (Talk) 18:55, 14 January 2006 (UTC)

iTunes

Automatic synchronization can be turned off in favor of manually copying individual songs or complete playlists; however, iTunes supports only copying music to the iPod but not from it, which has inspired third party software for the latter purpose. -itunes What are some good programs that do this?

Also, what is the key combination that prevents auto-synchronization from ocurring (so as to not wipe out an iPod if the computer doesn't have the same files). Thanks -Jian — Preceding unsigned comment added by JianLi (talkcontribs) 13:27, January 14, 2006 (UTC)

You don't mention whether this is on a Mac or a PC. So as far as programs, I would suggest going to some shareware site like http://www.shareware.com or the like and searching for a program for your particular platform. Although I can't testify to the legality of this since you could be trying to bypass copyrights by putting music that you bought onto your iPod then putting it on someone else's system who hasn't paid for the music. So, to borrow a phrase from another of my past times... Tread lightly... Dismas| 21:18, 14 January 2006 (UTC)
There's nothing inherently illegal about wanting to copy from an iPod back to a Mac or PC. Most people want such a feature purely for backup purposes; if something happens to your computer's hard drive, at least you can use such programs to copy the data back to the new hard drive you install in your computer. --Aaron 04:55, 15 January 2006 (UTC)
JianLi: The key combination is CMD + Option on the Mac and Shift + Ctrl in Windows. Please read this page before connecting your iPod to the other computer just to be on the safe side (it's just two short paragraphs). As for programs to copy from the iPod to the computer, I personally like Senuti and iPodRip for Mac OS X and iPod Access for Windows, but there are plenty of programs that perform this function. Visit Versiontracker for Windows or Versiontracker for Mac OS X and run a search on "ipod copy" or "ipod sync" if you'd like to see what other programs are out there. --Aaron 04:55, 15 January 2006 (UTC)

Neurology

Can neurology ( meaning my brain's chemistry and structure) and my experiences, acount for all my feelings and thoughts? even my most abstract ones? I need to know this, because I am a psychology student torn between the phisicalist theories and the theories that say that my brain is some sort of radio reciever and my mind is something more ethereal or whatever... I particularly don't prefer one or the other...well I think I'd rather be just a mamal that can be explained by neurology, but the other theory doesn't bother me too much, what bothers me is not knowing which is true, so I was wondering if there has been any conclusive neurology breakthrough that settles this question.--Cosmic girl 17:57, 14 January 2006 (UTC)

That is a fairly hot topic these days. Consciousness covers the issues pretty well. Bottom line, there is no right answer on this one unless you already have a preconceived notion.--Puck 18:02, 14 January 2006 (UTC)
Mind-body problem is another article that discusses the issue.--Puck 18:04, 14 January 2006 (UTC)

what to u mean by there's no right? there's no right yet maybe... but I'm confident there will be! :D... I've already read those, but are u sure there's no consensus yet? because I think that the phisicalist view is ahead of the mystical one, because of the advanes of neurology and how some regions of the brain correspond to certain habilities and senses, but I've also read some weird stories that maybe are true but I find it hard to believe... one is that a guy had almost no brain because he had hidrocefalia (I misspelled that I guess)and he functioned normally...so, but I can't believe everything I read so ...--Cosmic girl 18:12, 14 January 2006 (UTC)

In my opinion the materialist perspective is a tautology. It is the best approach to those things that are susceptible to empirical analysis--hence the wonders of science--but it dismisses anything that cannot be so analyzed as non-existent rather than just saying they are beyond its scope. Gnosis is often outside the realm of objective analysis and cannot be subjected to materialist investigation. However, any claims regarding its objective truth are subject to investigation and should be tested rigorously.--Puck 19:00, 14 January 2006 (UTC)
Many have been the claims that "X cannot be subjected to materialist investigation". Such claims stimulate research; scientists take them as a challenge. If you have not seen it, you might want to read Crick's book The Astonishing Hypothesis. --JWSchmidt 19:27, 14 January 2006 (UTC)
I think what that person means by "no right answer" is that, as you say, there's no right answer yet. Certainly the view that mental phenomena are explicable entirely in terms of physical phenomena is the one currently most widely accepted by experts - neurologists, philosophers of mind, that sort of person. But like just about every other opinion in philosophy, that view has its problems and there are some people who don't believe it. I think most philosophers who buy the physicalist view do so becaus 1) it has fewer problems than the dualist view, and 2) science seems to be pointing in that direction. The answer to your question, though, is that there is no answer yet. I suggest reading on the topic and making up your own mind. --George 20:45, 14 January 2006 (UTC)

thanks a lot,you all gave me very useful responses. --Cosmic girl 22:54, 14 January 2006 (UTC)

What does /opt in UNIX stand for ?

In UNIX operating systems, there is a standard directory by name /opt. Is it an acronym ? What does it stand for ? Filesystem Hierarchy Standard has got meanings of all standard directories except /opt. Jay 18:17, 14 January 2006 (UTC)

See . Its name stands for optional. – b_jonas 18:34, 14 January 2006 (UTC)

why do a needs assessment?

I Googled "needs assessment" and this was on top of the list: --Mattopaedia 23:50, 14 January 2006 (UTC)

Baryons 2

Is there such a thing as a Theta (Θ) baryon?

Google search for "theta baryon" - it is apparently an Exotic baryon. If your question is "is their existence widely accepted or are they merely conjectured" I can't help you. -- Rick Block (talk) 21:24, 14 January 2006 (UTC)

Automated time updating for *n*x

I currently use ntpdate tick.usno.navy.mil to set the clock on my slakware box when I think about it. The problem is I don't often think about it. It's been up for 85 days and I just reset the clock because it was off by about 10 minutes. Would it be better to run it as a cron job or with at? Or is there some better way? Whichever way you suggest, a clue about syntax would be appreciated as well.--Puck 20:44, 14 January 2006 (UTC)

The standard way to do this is to run a Network Time Protocol client. You might want to google "ntp slackware". -- Rick Block (talk) 21:11, 14 January 2006 (UTC)
I thought ntpdate was an ntp client. But I did do the google search you suggested and found the syntax for adding it to root's crontab. Thanks.--Puck 23:32, 14 January 2006 (UTC)

Fibrinolysis

Hello I was jus wonderin if you can give me a simple explanation of fibrinolysis as i am very confused on this matter. Thank u very much Lawrence

Have you read the article on it, see Fibrinolysis? -- Rick Block (talk) 21:03, 14 January 2006 (UTC)
Its a pretty simple article if you ignore the heavy biochem in the second paragraph Mattopaedia 00:14, 15 January 2006 (UTC)

January 15

Involuntary movement in the face

Sometimes I get involuntary small movements on my face, usually either near my eyes or lips. They feel like one small muscle is flexing at its own will. What is this called? Lapinmies 00:24, 15 January 2006 (UTC)

Try tic. --69.154.179.63 01:05, 15 January 2006 (UTC)
Technically it is a fasciculation rather than a tic. The distinction is a fine one. alteripse 03:18, 15 January 2006 (UTC)

malnutrion

Are you looking for malnutrition? If you need spelling help, please use Google or dictionary.com next time. --AySz88^-^ 03:25, 15 January 2006 (UTC)

Ships

Why do ships float? Can you provide data about ships such as cruise liners - weight, volume, etc? Thank you, in advance, for your assistance.

Robert Bost

The float because of Archimedes' principle. -- Finlay McWalter | Talk 03:12, 15 January 2006 (UTC)
See also List of cruise ships for info on tonnage, etc. Johntex\ 03:30, 15 January 2006 (UTC)