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Bomb detection

What methods/devices does the military currently use to detect explosive devices? For that matter, what are most explosive devices (for instance those made by insurgents in Iraq) made of? How could they be detected? Is anyone developing an all-purpose IED detector? This has puzzled me, since it seems like a high-priority question for a budget-rich military, and not obviously infeasable. Some kind of radar or sonar device for scanning the road ahead? Thanks, --Bmk 00:26, 22 June 2006 (UTC)

My (limited) understanding about explosives detection is that you do it by chemical analysis of one form or another, either by having a bomb-sniffing machine of some sort or a bomb-sniffing animal of some sort (i.e. a trained dog). According to the "detection" section of our article on IED's (Improvised_explosive_device#Detecting_and_disarming_an_IED) attempts have been made at remote universal IED detectors but have not yet been successful despite a lot of funding going into it. --Fastfission 00:55, 22 June 2006 (UTC)

Living on a military base, I've seen a lot of cool stuff. The best they could do is a chemical sensor that senses certain chemicals commonly found in IEDs. But that would take a stationary explosive, that has a self detonation, instead of one where the bombmaster can detonate when he chooses. — The Mac Davis] ⌇☢ ญƛ. 01:37, 22 June 2006 (UTC)

I wonder if some kind of sonar-imaging with some computer-aided pattern recognition would do the trick. Thanks for the replies. --Bmk 01:46, 22 June 2006 (UTC)

There are many people around the working on this, the problem is that there is no way to tell exactly what explosive someone will use. While you can look for traces of common chemicals used in bomb making (that is what they are doing in airports when they 'swab' your baggage), you need to get close enough to take a dust sample, which, on a battlefield isn't going to help you much. For a simpler case, look at some of the methods and equipment used in mine detection - there is not 100% reliable way to detect mines still. A major issue with IEDs is that you have to be able to detect them before you get within the effective blast radius for the information to help you. It's a difficult problem indeed. I doubt sonar would help, because it's not very accurate, and you don't know in advance what shape the explosive is. Trollderella 02:11, 22 June 2006 (UTC)

It woiuldn't work fast enough. I think you are talking mainly about rockets and such? That's the problem. Projectiles move way too fast for detectors, even with today's best technology. — The Mac Davis] ⌇☢ ญƛ. 02:31, 22 June 2006 (UTC)

No, I was thinking of buried or concealed explosives, like those used to attack convoys along roads. --Bmk 12:13, 22 June 2006 (UTC)

The difficulty in spotting IEDs with a visual method (like sonar) is that by definition they are improvised and probably non-standard in shape (though I suppose if you could x-ray something you would have an idea of its internal structure and texture and perhaps do something with that...). Using a chemical method improves on that a bit since there are a limited number of materials they are made from. It'd be really awesome if you could combine the two -- if you were able to "see" certain chemical concentrations in a visual way ("Gosh, an awful lot of ammonium nitrate over in that area..."). But I am not a scientist. :-) --Fastfission 16:55, 22 June 2006 (UTC)

A different, but related topic you may also be interested in missile or airborne threat detection. The standard techniques for detection of such threats include radar (bouncing a radio wave off of the reflective metal); infrared detection of heat (hot gases from a jet or rocket engine); or optical surveillance. Often, several tracking systems are combined to maximize detection of the threat. Finally, automated systems attempt to follow and destroy the target. Such areas are actively researched and advancements are continuously made. Nimur 19:04, 23 June 2006 (UTC)

Need help in physics

If this is house that has vents And there are also vents at the soffits then what is the difference in pressure if the wind 65 mph comes from the side of the house. Say wind comes form North to South then what is the difference in pressure between North and South part of the house. Plus how can I figure out the difference in pressure between attic and exterior. Hope you will be able to help me. Kind regards. Thank you You can write to me directly at address removed to prevent spam Your help is greatly appreciated.

What the heck are "the soffits"? --Bmk 01:44, 22 June 2006 (UTC)

Soffit. --LarryMac 17:58, 22 June 2006 (UTC)

Oh my god, why do you have 65 mph winds? Are you just meaning "hurricane speed winds?" I can't imagine you regularly experiencing them. As for your question, there is no way to tell without measuring because it would be tough for you to convey to use the schematics of your vent system and erm... soffits. The pressure will be greater on the north side of the house than the south. — The Mac Davis] ⌇☢ ญƛ. 01:49, 22 June 2006 (UTC)

HA! I KNEW this would come in handy some day! *gets out his pocketbook because he he's had 3 Palms and they all sucked*

Force = 0.004 x (The area of the wall) x (Windspeed)²

That's F=0.004Av² --mboverload@ 02:18, 22 June 2006 (UTC)

Nice formula, but I was thinking he ment air pressure. Now that I read it again, you may be right. — The Mac Davis] ⌇☢ ญƛ. 02:35, 22 June 2006 (UTC)

If you simply the problem a bit, ignoring compressibility (reasonable at these windspeeds) and sofftis (which I have no idea what they are) it boils down to stagnation pressure, which is ${\frac {1}{2}}\rho V^{2}$, where $\rho$ is the air density and $V$ is the wind speed (in metric units, please!). The result will be in pascals. So the pressure on the upwind side of the house will be the ambient pressure (current atmospheric pressure) plus the stagnation term I just quoted, and the pressure on the downwind side will be the ambient pressure - thus, the pressure difference is the stagnation term. The difference in pressure between the attic and the outside will be the same. — QuantumEleven 06:20, 22 June 2006 (UTC)

As to what soffits are, there is a good reference source on the web for all kinds of things. Here is a link to its entry on soffits: [1]. --Lambiam^Talk 09:15, 22 June 2006 (UTC)

Leg length

Once in a while one leg will feel longer than the other. The effect will pass in a few hours, but what could be the cause? - RoyBoy ⁸⁰⁰ 01:53, 22 June 2006 (UTC)

Some kind of pinched nerve is my guess. Like it says at the top of the page, asking a real doctor - your doctor - is 10000x better than here =D --mboverload@ 02:13, 22 June 2006 (UTC)

Then again, some of us are doctors. — The Mac Davis] ⌇☢ ญƛ. 02:36, 22 June 2006 (UTC)

Was that an implication that you were a doctor, at 14? Philc _T^E_C^I 13:26, 22 June 2006 (UTC)

I heard that one of legs is actually shorter than the other (I think it is the right leg that is shorter). That is supposed to be the reason why the guys lost is desert go in big circles, even if they think they are walking along a straight line. I am not sure about this, though -- Wikicheng 04:00, 22 June 2006 (UTC)

One leg is almost always shorter/longer than the other. Usually the difference is quite small, and it can change from day to day as the soft tissue in the joints is stretched or compressed. Differences can also arise due to differences in the lengths of the major bones of the leg; in those cases corrective orthotics or even surgery may be required for a normal gait and to stave off posture-related problems down the road. TenOfAllTrades(talk) 10:52, 22 June 2006 (UTC)

How long should a man's legs be? Long enough to reach the ground.

Long enough to reach his torso.

Whose legs are you feeling? --Dweller 13:30, 22 June 2006 (UTC)

Biological Evolution versus Intelligent Design

A recent revival of the anti-evolutionary "argument from design" holds that biochemical pathways are too complex to have evolved, because all intermediate steps in a given pathway must be present to produce the final product. Critique this argument. How could you use the existing diversity of metabolic pathways that produce the same or similar products to support your case?Patchouli 02:17, 22 June 2006 (UTC)

Similar to the "How do different animals have different number of chromosomes"? There might not be an answer, but good luck. I'm a believer in Evolution but it does have some problems because we still know quite little about biological systems. In fact, I think they just had to revise how they thought some part of a cell worked a few months ago. --mboverload@ 02:20, 22 June 2006 (UTC)

Is this a homework assignment?--72.78.101.61 02:49, 22 June 2006 (UTC)

• Yes.Patchouli 03:24, 22 June 2006 (UTC)

Congrats on the honesty. --Dweller 11:43, 22 June 2006 (UTC)

The fact that we do not know everything about biological systems does not mean "evolution has problems". Almost everything we know about the workings and inheritance of biological systems we have learned since 1860. Every major new discovery since Darwin has supported or is compatible with the basic concepts of evolution. You cannot name a single important new aspect of understanding of animal physiology, cell biology, or genetics that is incompatible or contradicts it. It is the single most useful concept about biology introduced in the last 2 centuries. alteripse 03:40, 22 June 2006 (UTC)

The Talk.Origins Archive website has a huge collection of standard creationist claims and refutations thereof...might be worth a visit. DMacks 04:07, 22 June 2006 (UTC)

You are correct Alteripse...I'm not sure what I was trying to get at. Hm. --mboverload@ 07:19, 22 June 2006 (UTC)

Second reading the TalkOrigins Archive. Two points to start you off:

• A particular pathway might not produce the same endproduct if a component is removed - but perhaps the resulting product is nearly as good at the task - or is useful for something else entirely.
• The creationist argument assumes that the only way for evolution to operate is to add components to a pathway - but there are other ways for mutations to occur: joining existing pathways, stitching pathways together, altering steps; in particular, removing steps from longer pathways.

EdC 11:06, 22 June 2006 (UTC)

That should read "One creationist argument is to assume...". There's no shortage of creation arguments and no shortage of refutations. And vice versa for evolution. That's what makes is so much fun. All you need to remember is that both are correctly called "theories". Could be that neither is right, thought about that yet? <grins> --Dweller 11:43, 22 June 2006 (UTC)

Creationism isn't a "theory" – certainly not in the scientific sense – as it is not falsifiable. It's arguments against the legitimate theory of evolution almost always amount to pointing to the next gap in scientific understanding, and saying "Oh yeah? I bet you can't explain this! Therefore, there must be a Creator (ahem...Intelligent Designer...)." When an explanation is forthcoming, creationists can just point to the next gap in understanding. See God of the gaps. TenOfAllTrades(talk) 11:55, 22 June 2006 (UTC)

Not sure what you mean by "legitimate". Do you mean there's one evolution theory that's correct and many others that are wrong, or do you (as I suspect) mean that evolution is Truth? As I understand it, you want to have your cake and eat it. You want to decry creationism because it cannot be disproved and you want to knock creationist attempts to disprove evolution! Let's face it. It's an argument neither side will win. Probably because neither is true and really the world was made by Slartibartfast. --Dweller 12:12, 22 June 2006 (UTC)

"Legitimate" probably being an actual "theory" in the scientific sense. Note the context is as a counterpoint to creationism not being a "scientific theory". An oft-seen creationist ploy is to say "see? even scientists themselves admit that evolution is just a 'theory', so our competing theory is just as valid", forgetting (to be generous about their motives) that the scientific meaning of "theory" is different than the common-language word. DMacks 15:30, 22 June 2006 (UTC)

Why are you so sure that creationism could never be disproved? --Dweller 16:29, 22 June 2006 (UTC)

Because it generally doesn't allow for testable questions. (See our article on falsifiability to understand the specific relevance of this to the definition of a "theory") Many individual statements of Creationists can be disproved, of course, but as a whole when you have a system predicated upon an omnipotent agent then you can explain away anything. --Fastfission 16:50, 22 June 2006 (UTC)

(moving back here, cos I'm not a right-winger)

You couldn't explain away Slartibartfast's home movies?

It's a pointless argument anyway. It doesn't matter how good either sides proofs are... the creation lobby will never concede that evolution is truth and the upholders of evolution will never concede that the world was created by a mysterious omnipotent being. With or without a long, white beard.

If creationists ever came up with a "winning" argument, science would be just as slippery as you aver creationists are... I doubt you'd see blokes in white coats rushing out to their nearest church/synagogue/mosque/long pole in the middle of the desert. The scientists would at best acknowledge that evolution was a flawed theory and they'd then sit back and wait until someone came up with a better one, while continuing to insist that creation isn't even a theory. --Dweller 18:42, 22 June 2006 (UTC)

Not quite. The ends of scientists and creationists are markedly different. Science is looking for understanding and predictability. If god or UFOs or the Flying Spaghetti Monster appeared and explained that they were soley responsible for every species on Earth and all of our evidence for Evolutionary Theory was fabricated, scientists would think that was great and they'd want to understand how the "designer" did such an amazing thing. We would take the new evidence (which would have to be extraordinary) and try to figure out every little detail of its operation. Creationists do not have that end. They just don't want there to be thoughts and ideas that contradict the word of their god as presented to them in form of the bible.

Additionally, it's really not quite that funny—in the United States, at least. It's really more along the lines of shocking and horrifying. Here we have ignorance versus reason and in the minds of the masses the winner is not clear. What will the creationists see as the next threat to their way of life? —Bradley 19:11, 22 June 2006 (UTC)

biochemical pathways are too complex to have evolved is an assertion with a precise mathematical requirement. Without the math proving that it's "too complex" and identifying all conceivable intermediate steps, the argument is a merely a failure of the human imagination without scientific merit. But hey, if the creationists could prove it, then we'd have to say they might be on to something... Peter Grey 22:39, 22 June 2006 (UTC)

It's possible that you might want argument from poor design, an opposite (somewhat) observation for the opposite conclusion. —AySz88\^-^ 04:34, 23 June 2006 (UTC)

You could make a point with yourself: For you to exist an incredible amount of steps of procreation must have been completed successfully. That means that every single one of your ancestors must have survived until they were able to procreate in spite of all the illness, disasters and so on that have happened throughout time. Just going back 31 generations means that 2^32-1 (roughly 4 billion) specific persons must have survived for you to exist - and yet you do! Hamstro (Talk) 17:17, 28 June 2006 (UTC)

Equation out of the Middle East

I: Since at least the year 1300, no human out of the Middle East has ever contributed a mathematical equation or formula.

Joe: You are wrong; this can't be. You are offending the intelligence of Middle Easterners.

I: This is the bitter truth. I never said there are no mathematicians or scientists who understand every equation or formula that has been discovered. I just say that there is not been an original contribution since at least 1300. To prove me wrong, I ask that you name a specific person with the specific equation that he came up with like the Schrodinger equation.

Joe: I am at a loss.

I wish to verify with more knowledgeable people whether I am correct. I appreciate any response in advance.Patchouli 02:25, 22 June 2006 (UTC)

May be right, since around then they have not contributed much to world society. — The Mac Davis] ⌇☢ ญƛ. 02:37, 22 June 2006 (UTC)

Hmm, let's see... the Turkish mathematician Cahit Arf has some things named after him. Does that count? —Keenan Pepper 02:41, 22 June 2006 (UTC)

I couldn't find a specific equation. I don't want principles. In addition, Turkey is generally considered European according to the Middle East article.Patchouli 03:18, 22 June 2006 (UTC)

Mergelyan's theorem is named after Armenian mathematician Sergey Mergelyan. —Keenan Pepper 02:45, 22 June 2006 (UTC)

And don't forget Israeli cryptographer Adi Shamir, the S in RSA. —Keenan Pepper 02:49, 22 June 2006 (UTC)

Do half-Middle Easterners count? Michael Atiyah is half Lebanese. --ColourBurst 04:52, 22 June 2006 (UTC)

I personally believe Michael Atiyah is one of the greatest living mathematicians; nevertheless he was neither born in Lebanon nor received any substantial schooling in the Middle East.Patchouli 05:20, 22 June 2006 (UTC)

I have a little trouble with this. The original statement was "no human out of the Middle East...", not "no human born and trained in the Middle East...". One implies something about the people; the other implies something about their circumstances. --ColourBurst 07:16, 22 June 2006 (UTC)

In the vein of literalnesss, a person born in Great Britain has not sprung out of the Middle East. One could even argue that Martin Van Buren was Dutch, Steve Jobs is Syrian, and so on.Patchouli 08:11, 22 June 2006 (UTC)

• I am interested in the Middle East composed of Arabs, Persians, and Afghans. Definitely not someone from a former USSR state; while Israel is in the Middle East, I should have said excluding Israel.Patchouli 03:18, 22 June 2006 (UTC)

Until now, I've assumed good faith but since Israel IS in the Middle East, your question is undermined. Are you asking about anyone born in a Muslim country and if you are, why not say so? Sadly, you've given me evidence to subdue my good faith assumption and suspect your motives. --Dweller 11:52, 22 June 2006 (UTC)

• Yes; a Muslim country in the Middle East — since I do not fear betting that no one born and educated in Indonesia, Senegal, Nigeria, Sudan, et cetera ever came up with an equation. I made the mistake in good faith because I should have said a Muslim country in the Middle East. Therefore, I apologize for this error. I thought maybe there is an obscure equation that I know nothing about and I have no motives to belittle any nation. I basically wanted to extract a fact since I am not infallible and don't know every equation.Patchouli 02:11, 23 June 2006 (UTC)

• No equation is going to be fairly hard to verify, but Mac Davis is correct above: there's a marked shift from possibly the most advanced civilization mathematically around 1000 CE to a near-complete lack of scholarly interest by 1300 or 1400 CE. I would expect that blanket statements today are incorrect, though, as (even if the culture in the Middle East isn't yet shifting) students from the region are increasingly studying at European and American (and other) institutions where good mathematical work is being produced. I would expect that such work also continues in regional institutions, and that it has to some degree or other all along.

  Quick summary: the absolute is almost certainly false. The general case (the decline of Middle Eastern contributions to mathematics) is almost certainly true. — Lomn | Talk 04:33, 22 June 2006 (UTC)

• I already know about Mahmoud Hessaby, for instance, yet over the past few weeks my sporadic research on him did not unearth a single equation.Patchouli 05:20, 22 June 2006 (UTC)

Ahmed H. Zewail Egyptian, Nobel Chemistry. Abdus Salam, Pakistani , is that close enough? Nobel, physics, ElectroWeak theory --GangofOne 06:37, 22 June 2006 (UTC)

• I didn't know who Ahmed Zewail was; this anwer is on target especially since Egypt is always classified as a Middle Eastern nation.Patchouli 07:24, 22 June 2006 (UTC)

• I thank everyone for its responses notwithstanding my further request that if there is a specific equation discovered by a Middle Eastern individual that you provide a link for it or paste it hereon.Patchouli 07:32, 22 June 2006 (UTC)

A non-Israeli Middle Eastern, you request (above). What about a Jew born in, say, Iraq? Or a Christian born in, say, Oman? --Dweller 16:33, 22 June 2006 (UTC)

• Fundamentalism & mathmatical advances don't exactly go hand-in-hand. Mayor Westfall 12:25, 22 June 2006 (UTC)
  • It is worth differentiating between authoritarianism and fundamentalism in the case of the Middle East. Much of the Middle East is under some form of authoritarianism which is not rooted in religious fundamentalism (i.e. Syria). --Fastfission 16:46, 22 June 2006 (UTC)

Many pioneers who came up with equations were born and raised in the authoritarian regime of the Soviet Union.Patchouli 06:06, 23 June 2006 (UTC)

• • • Well it was the collapse of early Islamic philosophy at the hands of opposition from key scholar/theologians like Al-Ghazali that triggered a return to theological fundementalism and the abandonment of scientific thought circa early 12th century AD. Just as a form of Christian fundamentalism might be said to have ushered in the dark ages in Europe, fundementalism played a key role is impeding the progress of science and mathematics in the Islamic world as well. Dragons flight 21:45, 22 June 2006 (UTC)

• Even Al-Khwarizmi in 800s CE did not contribute an equation that I can find. I have concluded that he simply rehashed Diophantine's Arithmetica in Arabic.Patchouli 00:33, 23 June 2006 (UTC)
  • I think he contributed a technique (or several) for solving equations. You should remember that equations are not a particularly important output product of math research. If anything, theorems would be what you'd want to look for. Someone like Galois who is very important, contributed the fact that there's no equation of a certain form, and so if he happened to be middle-eastern you wouldn't ve counted him either, I take it? --Ornil 03:55, 23 June 2006 (UTC)

No; I wouldn't count Galois notwithstanding his enormous accomplishment. As I stated first, I am simply interested in a meaningful equation with a principle - like a theorem - tied to it like the Einstein photoelectric equation or the Compton wavelength equation. This is what I am searching for.Patchouli 04:37, 23 June 2006 (UTC)

Is there any relevance to this question? Or is it just a very contrived way to point out that the heyday of mathematics in the Islamic world is a thing of the past? Formulating it as a question suggests sincerity. Similar question then. How does Russian scientific literature fare since the fall of the Soviet Union? It used to constitute 1/3 of the world's scientific literature. But I don't know what it's like now. So a legit question? Or am I trying to make a point, whithout actually making it, so that that can not be held against me? (sneaky, sneaky) DirkvdM 08:16, 23 June 2006 (UTC)

• Not necessarily since I learned who Cahit Arf and Ahmed Zewail are as a result of this conversation. I will close this discussion because it is becoming very lengthy without achieving any intellectual purpose.Patchouli 10:19, 23 June 2006 (UTC)

Oi! I'll decide when this discussion is over! Ok, it's over now. :) DirkvdM 17:56, 23 June 2006 (UTC) No, it isn't .... DirkvdM 06:08, 24 June 2006 (UTC)

The biggest problem is that you're mistaking two claims:

1. No equations were developed in the Middle East
2. No Western educational system teaches about Middle Eastern mathematical developments.

I have heard from reputable research historians who specialize in the History of Mathematics that an entire career can be made simply by learning Arabic and proceeding to translate literally thousands of archived documents which are essentially un-studied by Western historians. The biggest problem is that concurrent developments in the Middle East during the 12th through 19th centuries went largely untranslated because of the animosity and xenophobic divide between Arab and European cultures. To claim that no mathematicians (or equations) came from that region is a very strong argument based solely on the premise that we do not know of them. Nimur 19:21, 23 June 2006 (UTC)

Of course, something similar goes for Russian scientific literature, and I forgot to mention that. Chinese literature too, and that's 1/5 of the world's population. Now China has always stuck to its own affairs, so it's not that likely they will translate it themselves (who for?). And with the way thingsa are going in Russia, it doesn't seem likely it will happen there either. But many Arabic countries have plenty money, so they can afford to hire people. But then I suppose that is what you are saying. I'm unemployed and good at languages. Thanks for the tip! Where do I apply? :) DirkvdM 06:08, 24 June 2006 (UTC)

The original question is an obvious (and obnoxious) troll, but I can't pass up the opportunity to mention that some of the most remarkable theorems in modern mathematics come from Saharon Shelah, who was born in Jerusalem and whose extraordinary contributions have been widely recognized. See also this archive Shelah's papers. The question specified "formulas", but I am guessing that he doesn't know enough about modern mathematics to know that he probably meant "theorems". But in a sense too technical to explain here, Shelah's work is related to combinatorics, a subject well known for its beautiful formulae.

There are many, many other examples. To mention just one which comes to mind, one of my former professors was born in Turkey, and he is a leader in his field. I am sure that if I bent my mind to the task, I could come up with other examples. ---CH 08:57, 26 June 2006 (UTC)

Of course, five seconds after I sent that I remembered that Branko Grünbaum (who was on my thesis committee) was also born in Israel. Grünbaum has enjoyed a long and very distinguished career in convex geometry and allied subjects. Much of his work has involved hard classification theorems in geometry, but his well known book on convex polytopes contains plenty of nice combinatorial formulae. Even nonmathematical readers might know his book with Shephard on tilings. ---CH 09:03, 26 June 2006 (UTC)

Yeah, but the poster specifically excluded Israelis from this, thus excluding Shelah and Grünbaum. --Dweller 09:25, 26 June 2006 (UTC)

Most effecient device

What is the most effecient device for converting electricity to light? I heard that they use LEDs in some torches which give light of brightness comparable to the incandescent bulbs. Are the LEDs most efficient? -- Wikicheng 04:13, 22 June 2006 (UTC)

I don't want to commit to most efficient, but LEDs are more efficient than incandescent bulbs. LEDs also have an advantage in being practically unbreakable. — Lomn | Talk 04:18, 22 June 2006 (UTC)

The nuclear bomb. (In addition to electricity, a minimal amount of mass is also converted to light. There is also considerable heat by-product.) Hope this helps.

But like you said, a minimal amount of mass is also converted to light, so they would be terribly inneficient. Philc _T^E_C^I 10:36, 22 June 2006 (UTC)

I don't know how efficient they are, but arc lamps are fucking bright. That article also has a nice table at the end, which is a template I'll insert here:

You might want to look through those. You should also consider the fact that it probably matters to you what frequencies energy is concentrated in (for example, reflective biker gear I heard is brighter because it takes many ambient frequencies and redirects the energy into one bright [say, orangey] wavelength, obviously not reflecting more energy than it absorbs however seeming much brighter). In theory, of course, any electricity you're not producing heat with is 100% converted to "light" but is this enough to tell you how efficient it is at the part of the spectrum you're interested in producing light at?

I was looking at a device which can probably used in a hand torch (flashlight). I can not include a nuclear bomb in this. Moreover, I an trying to convert electricity and not mass to light. Anything close to white light is welcome -- Wikicheng 11:38, 22 June 2006 (UTC)

Could you fit some glow worms in your hand torch? --Dweller 11:55, 22 June 2006 (UTC)

Not a bad idea though! :-) -- Wikicheng 12:56, 22 June 2006 (UTC)

Apparently Organic light-emitting diodes can be made almost 100% electricity-to-light, but very much "in development". Otherwise low pressure sodium Electric lights are the most efficient, but the light is pure yellow - no other colours - and the tube is large. For torch size the white torch LEDs are reasonably cheap, but seem to be less efficient than flourescent lamps (40 lm/W vs 50 lm/W). I haven't seen a standard torch-size flourescent source that gives bright enough light though, they all use pretty long tubes. So LEDs seem the best for smaller torches, fluorescent tubes for larger battery powered area lighting. A 2 or 3-cell (1.5 V cells) torch can be converted to LED by buying an LED and fitting it in the reflector without any other conversion (not a bright light though). --Seejyb 22:58, 22 June 2006 (UTC)

Well, that very much depends on the brand of light. :) Some of the tactical flashlights have LED conversion kits that are still very bright flashlights. :) kmccoy (talk) 10:32, 23 June 2006 (UTC)

Amount of water in dew

In a cubic meter of air with a humidity of 70% how many liters of water would they be in it? and what is the formula for calculation?

Regards, Albert W Howard

Well, since 70% means a relative humidity, it's going to depend on the temperature. A cubic meter of air can hold more liters of water if it's warmer. There's some information at Humidity, but probably not all that you need. Melchoir 04:25, 22 June 2006 (UTC)

I googled "how much water can a cubic meter hold" and one of the results is this everything2 write-up (remember everything2? Ah, the days before wikipedia...):

         Air temp,   Water content of
         deg C       saturated air,
                     gram/cubic meter
         --------    ----------------
         -10               2.1
           0               4.8
          10               9.4
          18              15.4
          20              17.3
          30              30.4
          40              51.2
          50              83.0
                         .....
          90             423.5

so as you can see, you need to know the temperature. Read the writeup I linked, it's very interesting. Unfortunately, I don't know if "70% humidity" or saturation is just 70% of the gram weight of the water, since it's conceivable that another scale (logarithmic or something, or volume, or...) is used. This is what relative_humidity says: "Relative humidity is the ratio of the amount of water vapor in air to the maximum amount of water vapor that could be in the air if the vapor were at its saturation conditions." I wish it would explicitly state that this is the same as grams of liquid water, or volume of liquid water, or mols of h2o or whatever. Anyway, I think it's safe to just multiply the gram/cubic meter by 70% to get 70% relative humidity, after deciding what temperature you want it at. Be sure to convert to liters of water / cubic meter, since that's what you asked for! 82.131.191.135 10:29, 22 June 2006 (UTC)

Actually relative humidity is the ratio of the actual vapor density vs the saturation vapor density. Getting the amount of water vapor in the air is not as simple as multiplying the water content at saturation by the relative humidity. If you are just interested in getting the result, google "psychrometric calculator" and you'll find links to numerous online calculator where you'll be able to input dry bulb temperature (the temperature of the air, T) and relative humidity. Results are usually expressed in g/kg of dry air in mass or % of volume (%vol). If you are looking for the amount of water in 1 cubic meter of air, use the result in %vol, multiply it by 1000 to get the liters of water vapor in your air (V). You then have to convert this value to normal conditions (0°C, 101325 Pa) using Vnorm = V * 273.15 / (273.15 + T). The mass of water you have in your air is given by M = Vnorm / 0.0224 * 0.018 (using 22.4 l/mol as an approximation of the normal volume of 1 mol of perfect gas and 18 g/mol for the molecular weight of water).

Meaning of "MMgy"

Please expand MMgy; apparently it is a unit of measure of liquid fuel.

From Google, it appears to mean "million gallons per year". Melchoir 05:34, 22 June 2006 (UTC)

Update: I've created Million gallons per year and MGY, with appropriate redirects. Melchoir 05:52, 22 June 2006 (UTC)

...and if someone knows which kind of gallon is implied, that would help. Melchoir 05:57, 22 June 2006 (UTC)

Binoculars

How can I measure or calculate the magnification factor of my binoculars?--Shantavira 07:11, 22 June 2006 (UTC)

It's going to be an even multiple, so maybe if you taped a piece of paper vertically to the wall opposite of you, after drawing a small rectangle at 1/10th size (for example, if your sheet of paper is 8.5 by 11 inches you could draw a 0.85 by 0.11 inch rectangle) in the same orientation, then you could look at the rectangle from one eye and the whole sheet of paper from the other eye and see if the apparent size is the same. Repeat with different ratios until you get the same apparent size. (It should be easy to judge, since if you do it right, the images come to different eyes but from the same plane and so they should line up nicely.) Try it and let us know.

Thanks. Yes, using both eyes makes a lot of sense. I hadn't thought of that. Rather than experiment with different sized rectangles I could use a whole line of sheets of paper as a scale, but in that case I might as well use the slats of my garden fence as a scale to compare with the magnified width of one slat. I have another pair of binoculars of known magnification, so I will try it using those first.--Shantavira 12:00, 22 June 2006 (UTC)

Yes it works. The paper rectangle idea turned out to be the simplest solution after all. --Shantavira 07:37, 23 June 2006 (UTC)

Environmental Question

Can you tell me about destructive distillation of wood?With Pictures please.--Saksham Sharma 11:03, 22 June 2006 (UTC)

This is an experiment that we do with our Year 8 classes (12-year-olds). The pupils heat some wood chips in the bottom of a test tube, and light the flammable gases which emerge at the mouth of the tube. Soon the flame dies down, and what is left inside the tube are fragments of charcoal and some brown tar. I believe that the flammable gas given off at the start is mainly methanol.G N Frykman 21:09, 22 June 2006 (UTC)

The Ultimate Speed Limit

I've heard that the Special Theory of Relativity's Ultimate Speed Limit applies not only to matter and material objects but to influences,disturbances,forces, and signals,etc of any sort.

I don't understand.I know that special relativity says that all matter and objects undergo changes as they move or travel and that they change back into their original state when they stop moving or stand still.I know that one of these changes is an increase in mass and that the mass of objects become infinitely large when they approach the speed of light.But that doesn't explain how things that are not material objects can't travel faster than light.

So how come things that are NOT matter can't travel faster than light?I mean, how can it and how does it apply to anything, not just matter and substances?

One way to look at it would be that if a signal could move faster than light, it would violate causality. Suppose you have two events, at different times and places: A) a person sends a signal, and B) the signal, arriving at its destination, causes a phone to ring.

Now, suppose you have some observers witnessing these two events. They're not all at the same place; some are moving at different, near-light speeds and in different directions. Because one's velocity affects time, according to special relativity, different observers will disagree about how much time elapsed between A and B. To one observer, there might be two seconds between A and B, while another observer might measure five seconds between A and B. However, as long as the signal traveled at the speed of light or slower, all observers will agree that B happened after A.

If the signal traveled faster than the speed of light, however, the math works out such that to some observers, it would appear that B happened before A! And it's not so much that B appears to happen before A; since observations in all reference frames are equally valid, B does occur before A for that observer. The effect would happen before its cause! Chuck 11:59, 22 June 2006 (UTC)

And this is the reason we have call waiting Mayor Westfall 12:18, 22 June 2006 (UTC)

The problem is that the non-matter things that carry forces, disturbances, influences, etc. are all either light or its cousins. Light, radio waves, x-rays, et al. are all photons with different energies—by definition they travel at the speed of light. Photons are actually responsible for all electromagnetic effects; all electric and magnetic fields are the result of photons being passed back and forth between objects, explaining why those influences can't travel faster than light—they are light.

Gravity is believed to be mediated by the exchange of particles called gravitons: massless particles that are like photons, but carry the gravitational force between bodies instead of the electromagnetic. The two other fundamental forces (the strong and weak nuclear forces) are similarly mediated by the exchange of particles. (There's funny stuff about the weak force and its associated particles that I don't want to go into; it doesn't affect the validity of this explanation, however.)

So we've got the 'stuff' of the universe that's made up of particles with mass that are limited (by relativity theory) to speeds less than the speed of light, and we've got the massless bits that mediate forces (interactions) which travel at the speed of light. All of the fundamental forces are associated with particles, so there isn't any way to generate an influence without using those particle intermediaries—all of which are limited by the ultimate speed limit. TenOfAllTrades(talk) 14:04, 22 June 2006 (UTC)

See faster than light, especially section "Apparent FTL". Conscious 18:36, 22 June 2006 (UTC)

This might not quite be revelant to the question asked, but if you were "travelling" at the speed of light, consider the Lorentz contraction of the rest of the universe - everything would be at zero distance. Then faster-than-light would mean you would have to start thinking about how to go zero distance in less than zero time. Peter Grey 22:53, 22 June 2006 (UTC)

But I was asking about how can and does it, I mean such a rule like that, apply to anything and everything, not just matter.Couldn't there be some kind of massless force-mediating particle, or some other unknown and undiscovered influence, which the changes associated with special relativity, and therefore the ultimate spped limit, doesn't apply to and occur in?

You can never conclusively know something undiscovered isn't there, but they haven't found any signs of one yet i.e. no known phenomena where an undiscovered faster than light effect is the best explanation. Peter Grey 04:14, 23 June 2006 (UTC)

Food

It seems like everything we eat is something that is made from a living soruce--e.g. animal/plant. Can anyone think of an example where this is not true? Also, why is this? Mayor Westfall 12:30, 22 June 2006 (UTC)

yeah, salt is the exception. I guess you could trace it back to the fact that humans don't do photosynthesis. (or, needless to say, organic atomic power).

The simple answer to your question is that the source of energy for animal metabolism is the energy released by breaking down energy-rich molecules such as glucose in cellular respiration, and some plant or animal has to create these energy-rich molecules (a.k.a. food) in the first place. Gandalf61 12:45, 22 June 2006 (UTC)

Some argue that petroleum is not from a living source(see abiogenic petroleum origin), though many believe it is from a living source. Many foods are made with petroleum. HighInBC 12:53, 22 June 2006 (UTC)

What foods are made from petroleum?! -Quasipalm 14:41, 22 June 2006 (UTC)

Pub grub. --Dweller 12:55, 22 June 2006 (UTC)

I wouldn't recommend it myself, but in Ancient Rome, lead salts were used as sweeteners. I have also read that in some countries, pregnant women eat clay as a supplement to their diet.--Tachikoma 16:56, 22 June 2006 (UTC)

What about something like Diet Coke? Both artificial flavors and sweeteners, but I'm not sure from what constituents these are produced from—could be peroleum distillates for all I know. —Bradley 17:49, 22 June 2006 (UTC)

Another bit of trivia: gold leaf is apparently non-toxic and can be eaten. I believe it was popular in the bad old days of Thatcher / Reagan. --The Gold Miner 18:08, 22 June 2006 (UTC)

Yes, E175 in Europe, see E number. You'll find a fair few inorganic substances on that list. Arbitrary username 18:49, 22 June 2006 (UTC)

But everything that was named is not nutritious. Conscious 20:39, 22 June 2006 (UTC)

Apparently there are bacteria that live in caves that no organic matter (or sunlight) reaches, which eat rock. Don't know about the metabolism details, though. DirkvdM 08:57, 23 June 2006 (UTC)

Perhaps you are thinking of SLiME? (Subserface Lithotrophic Microbial Ecosystem)Tuckerekcut 16:54, 23 June 2006 (UTC)

No, that's not it, but it reminds me of a different bacteria, fittingly named snottite. They corrode rock with their acidic drip, but don't eat rock. However, they eat sulphur, so it's still an answer to the question. DirkvdM 18:07, 23 June 2006 (UTC)

Well, if you're opening this up to non-humans, think of the ecosystems that have developed around undersea hydrothermal vents. These vents are also known as black smokers, and a variety of archaea and extremophile bacteria survive either from the dissolved chemicals in the magma-heated water itself, or even the faint glow that emanates from the black smoker.--Tachikoma 03:43, 24 June 2006 (UTC)

Water is not from a living source. It might contain living organisms or formerly living organisms, but it's not alive.

"not from a living source" ... I've done the math once and given the total volume of animals through time, I concluded that all water on Earth has at one point been piss. DirkvdM 06:12, 24 June 2006 (UTC)

Define "temperature equilibration"

Can someone please point me to a clear and concise definition of "temperature equilibration?" And specifically, does it occur when, say, a connecting door between two spaces--one warmer than the other--is opened, and the air allowed to flow between the two spaces? Thank you. --129.71.112.32 13:55, 22 June 2006 (UTC)

Temperature equilibrium is achieved between two bodies when their temperatures are the same, or equivalently, when both bodies' temperatures are no longer changing --198.125.178.207 14:03, 22 June 2006 (UTC)

I think you did not realize that the poster said "temperature equilibration". Look at the first few hits and see if the poster had the right definition. (Also, could pressure-temperature equilibrium of a gas figure in the definition?) 82.131.189.199 14:09, 22 June 2006 (UTC).

Buffalo Coin Value

On the Main Page there is a link to the article about the new Buffalo coin. It is a solid gold coin worth $50, but it is an ounce of gold. How can an ounce of gold be worth $50? Wouldn't it be easy to melt it down and sell it for pure gold? --Chris 15:18, 22 June 2006 (UTC)

The face value of the coin and its selling price are different things. The external links in the article mention the US Mint will sell the coin at price of gold + small premium; at today's price that would be in the USD 600 range. Later the "street price" will be what collectors are prepared to pay each other for the coin. 84.231.33.34 16:07, 22 June 2006 (UTC)

At $1.13 dollars per gram of gold, this thing weighs 31 g, so you would lose money by melting them and selling the gold. Philc _T^E_C^I 16:53, 22 June 2006 (UTC)

I don't see how thats possible. Mostly because gold is currently USD18.72[2] per gram or USD582.30[3] per troy ounce (which is 31 g). --Russoc4 17:51, 22 June 2006 (UTC)

My bad, I rephrase, at $582 per 31 g, this thing weghs 31 g and costs $800, so good luck on making a profit, you'll need it. Philc _T^E_C^I 23:55, 22 June 2006 (UTC)

Currently, the article mentions that its face value is $50, but it's issue price is $800. That means you have to pay $800 to get one American Buffalo coin from the U.S. mint. The $50 is not what you pay to get one from the mint; it's what the coin "counts as" if you use it as a coin. If you wanted to buy a $250 stereo, and for some strange reason you wanted to pay the store in American Buffalo coins, you'd need 5 coins. (This would be stupid, of course, since the market value is going to be at least the value of the actual gold in the coin, currently $582.30. But you theoretically could.) It's a bit confusing because with ordinary coins, the two numbers are the same--it costs $0.25 to get a quarter, and a quarter counts as $0.25 when you spend it. But those two numbers are not the same for all coins. Chuck 20:20, 22 June 2006 (UTC)

If you tried that at Best Buy, they'd probably have you arrested. --LarryMac 20:33, 22 June 2006 (UTC)

Thank you for explaining, Chuck, and thank you for making me laugh Larry :) --Russoc4 20:54, 22 June 2006 (UTC)

God that links funny, especially “It’s a sign that we’re all a little nervous in the post-9/11 world,”, what was he going to do with his smeared two dollar bill, give a policeman a paper cut!? I'm pretty sure a piece of paper has considerably less impact than a 777. Philc _T^E_C^I 00:04, 23 June 2006 (UTC)

Why does insulin stimulate glycolysis

I just read that insulin stimulates glycolysis - essentially the breakdown of glucose into energy. Why is this? It seems to me that this goes against the "normal" anabolic effects of insulin. Or is this simply what occurs in cell metabolism after glucose has been pushed into cells by the insulin? I'm confused. Anyone? Jack Daw 16:36, 22 June 2006 (UTC)

Insulin is reponsible of making energy ot of glucose found it the body. This is why you inject it to yourself if you have that specific illness (do not know the exact english name of it). Please consult the Book : Human Anthology for more specific answers. The brakdown of Glucose to Co2 happens in the cells, by ensims, so this has nothing to do with insulin, except that it is needed for it to happen. Ensims NADP and NADPH (if I remember correctly, couse I have learned it more than 8 years ago and have not used this knowlage since then) are responsoble of turning sugar into energy wich your body uses.--Mike

Let's try another explanation. In healthy people insulin rises when there is plenty of glucose around, like when you are digesting a high-carbohydrate meal. Insulin serves as a signal for many types of cells, stimulating some processes and inhibiting others. In general the processes stimulated by insulin are those that consume and store excess glucose, while the processes that are inhibited are those (in the liver) that produce glucose and release it into the blood. Glycolysis is an example of a process that consumes glucose, transforming it into energy and into substrates for storage or further synthesis. The opposite of glycolysis is the process of glucose production, gluconeogenesis, which is inhibited by insulin. alteripse 00:11, 23 June 2006 (UTC)

Got it. Related question: Is glycolysis more efficient in some people than in others? (Efficient as in how alcohol dehydrogenase can be more or less efficient...) [Btw, is glycolysis pronounced with emphasis on the O or Y :D] Jack Daw 20:38, 26 June 2006 (UTC)

Firstly the effect of insulin on the rate of glycolysis (specifically phosphofructokinase(PFK) activity, PFK being the rate limiting step of glycolysis ) is independent of the effect on Glucose uptake by cells that insulin has. While insulin stimulates the breakdown of Glucose (Glycolysis) it does not stimulate the Krebs Cycle, this leaves the breakdown products of Glucose - in the form of acetyl-CoA, an intermediate which can then go on to be used in the synthesis of lipids, so if as alteripse suggested you view the actions of insulin as being to promote processes which consume glucose then you can see that all the effects of insulin are in fact pulling in the same direction.

Data Flow Diagram

Question number1: What is the dataflow diagram to prepare a library management software?

Please post all of your homework questions at the same time so we only have to respond once with DYOH. --Kainaw ^(talk) 17:34, 22 June 2006 (UTC)

jvc video tape

←→§hello, could someone please help with my question.Iam trying to find out when JVC first launched its SX E-30 video tape many thanks –—…°≈±−×÷Alan Fry--80.41.71.23 17:58, 22 June 2006 (UTC)

You could start by asking JVC, rather than us? --Dweller 18:27, 22 June 2006 (UTC)

US Experimental High Speed Recon Crafts

I have been given the VERIFIED information, that a US military Recon Fighter Called "Aurora" exists. It has a speed of around 8 MACHS and uses RAMJET engines. I would like to ask if you have any information on this plane developped by france and sold to the US for use (france is currenly updating it as AURORA-II, with estimated speeds of around 10-12 MACHs. Please be warned, that this information was very hard to acquire and took me a couple contacts to get. What I found otu, is that it probably has a triangle shape and all engines are housed on under the wing. I am also missing the technical study aircraft of the russians (made by Mig)wich had a stealthy design and was capable of lifting weapons in it's two bays, each holding an A-bomb or 2 Aphid Heat seeking missiles. Both programs were considered Black, so no public informations were published.

Your answer can be posted to (blanked for privacy), due to the fact, that my other email addresses are probably being monitored.

Yours sincerely: (blanked for privacy).

Have you considered seeing what has already been written by people here at Aurora aircraft? --Kainaw ^(talk) 19:25, 22 June 2006 (UTC)

As it says at the top of the page, Wikipedia content is distributed widely on the internet, and putting your e-mail address here makes it very public. If you are concerned about your e-mail addresses being known, posting them on Wikipedia was probably not the best move.--Tachikoma 19:37, 22 June 2006 (UTC)

Browsing v Downloading

Forgive my ignorance of all things IT, but quite simply, is there a difference between Browsing and Downloading, or are they one and the same thing? Answers in non-techy speak please.

If you want to be anal, to browse something, you must download it first. Even if you are using remote browsing (ie: Remote Desktop), you have to download the image of what you are browsing locally. But, in common terms, browsing means you are just looking. Downloading means you are saving a copy for future use. --Kainaw ^(talk) 19:28, 22 June 2006 (UTC)

Thanks Kainaw, that's most helpful - but I will pass on the anal methinks.

Even some politicians don't seem to know this. In Dutch politics, there was a proposal to make the downloading of information that could be used for terrorist purposes illegal. The problem is, if you follow a link to a page that holds such info, you've already downloaded it. So you have to download the info before you can tell it's something 'illegal' (unless it's marked as such). DirkvdM 09:04, 23 June 2006 (UTC)

OK DirkvdM, to pursue your point: if a Dutchman innocently clicks on any link, and another webpage opens on his screen (whether legal or illegal), has he in fact downloaded it such that it will always be retrievable from his hard drive, even though he did not save it as per Kainaw's earlier explanation?

That depends on the web browser. 99.999999999% of the time, the answer is 'yes'. The page is stored in a "temporary" location on the harddrive and can be viewed later directly from the drive. I quoted "temporary" because web browsers tend to keep the files for a very long time. I've worked on people's computers that have "temporary" files that are over a month old. --Kainaw ^(talk) 16:31, 23 June 2006 (UTC)

OK and thanks. But what does our innocent but now worried Dutchman do after he has innocently clicked on the link and finds himself reading a notice from the Dutch Government that he has broken the law by doing so. Can he eliminate all evidence of his "crime", or does he destroy his hard drive, before they come knocking on his door to arrest him for his so called illegal activities?

All popular browsers have a way to delete temporary files. It is different for every browser. Usually, it is in settings or tools or something similar. --Kainaw ^(talk) 16:55, 23 June 2006 (UTC)

Thanks again. I was getting really worried about our poor Dutchman. I can now relax and let him concentrate on watching his national team win in their game next week against Portugal.

Thanks for rooting for us, but our innocent Dutchman is still not out of trouble. Deleting a file just makes the disk space available for future use. Unless the data is actually overwritten by other data, the info will still be there. You won't find it through normal ways, but there are ways to retrieve it. DirkvdM 18:15, 23 June 2006 (UTC)

Oh Dear. So he's back to destroying his hard drive then, before he can settle down to enjoy the match? And the lesson for the rest of humanity is to buy a crystal ball so that you can predict what is beyond the weblink you are about to click to ensure it doesn't contain anything illegal?

Actually, the trick is to avoid actions that would put you under suspicion to begin with. Is there one single example of a person who was investigated and arrested for visiting a website and doing absolutely nothing else that was illegal? There was a case shortly after 9/11 of a man (Nichols - forget his first name) who was arrested (and plead guilty) on something like 111 counts of child pornography. Nutjobs claimed he was arrested for looking at naked women that he didn't realize were underage. The truth: He was turned in by his mother for sexual assault of a little girl (6 or 7 years old - I don't remember). Police went to his house to investigate and found file cabinets full of photos of children, indexed by the sex act they were performing. After arresting him, it was discovered that the Feds were investigating him for online trade of child pornography. How this became a case of "an innocent guy who was abused by the system" completely escapes me. --Kainaw ^(talk) 23:48, 23 June 2006 (UTC)

Well, the thing is that that is exactly what was proposed in the Netherlands, to make the mere download illegal. The whole world is going apeshit and I'm surprised to find the Netherlands so much at the forefront of it (then again we've got the most right-wing coalition in ages at the moment). Innocent children in jail, people burned alive in a make-shift prison and mass extradition of immigrants (except when it's a party member of course). DirkvdM 06:27, 24 June 2006 (UTC)

There's the case of the guy who was arrested for using a uncommon web browser. --cesarb 17:23, 24 June 2006 (UTC)

Funny thing about those stories... The BBC News article makes no mention of the guy making a donation or using Lynx. However, some anonymous guy with a blog says that he has emails from the guy and we are to trust that he has the truth and everything else is a lie. I never trust anyone who claims to have heard the "truth" from some guy who knows some guy who heard about something from an email someone sent that came from some guy who worked someplace that contracted with someone who knew something... --Kainaw ^(talk) 18:22, 24 June 2006 (UTC)

This report on ZDNet seems more authoritative, with specific information about the trial. It implies that the guy didn't do what he was accused of doing, but the judge found him guilty anyway because he looked a bit shifty. --Heron 21:21, 24 June 2006 (UTC)

Yes, that is a much better article. It makes a lot more sense. From the defendents own statement, he donated money and thought it may be a scam, so he "tested" the security of the site in a manner that was illegal. In my opinion, that does not fall under the umbrella of "being found guilty for just visiting a website." --Kainaw ^(talk) 23:26, 24 June 2006 (UTC)

Now see what all this conflicting comment has done to our poor Dutchman. He took his eye off the ball whilst worrying that he was going to be arrested for innocently accessing a website he wasn't supposed to, and in so doing, he forgot to support his team and that loss allowed Portugal to go through to the quarter finals.

Just to start this one over again - in Australia, many ISPs give you a certain download limit, so you may get an ADSL plan with a 200Mb, 10Gb, or 40Gb limit per month. It isn't such a problem with the larger limits, but many with a 200Mb limit may think that "they haven't downloaded anything - i just check my email and look at web pages" without realising that the email and web browsing does count towards their download limit. I got this a lot when working at an ISP helpdesk (in the dial-up days). -- Chuq 04:02, 26 June 2006 (UTC)

Untitled Windows XP Install Issue

-Added heading to this question -Benbread 21:32, 22 June 2006 (UTC)

hi im trying to install a copy of wondows xp on ly laptop, but the instalation prosess ceeps going round in a loop, as it formats the hard drive then it copies files ot it, then it reebots and then so on in that sequence and i dont knwo what to do there is nothign in the instructions to help me. and i dont understand y it is doing this. (ps there is no former operating systm on the laptop as that was some hoe wiped form the hard drive and the recovery disks for some reason dont work) what should i do to install XP?

When the computer reboots do you press the key it prompts you to press, and if so don't. I always found that to be a stupid thing that seemed to confuse a lot of people. -Benbread 21:56, 22 June 2006 (UTC)

After you install the files, you have to take out the disk before rebooting, I think. Ok, back to Halo.

Teaching myself anatomy

I want to teach myself anatomy, to a doctor's level, profound knowledge. Would you recommend me any sources or good books? Thanks.

• Start here. Memorize every page. There will be a test. --jpgordon∇∆∇∆ 22:39, 22 June 2006 (UTC)
  • Seriously, all? Gaah! Jack Daw 23:04, 22 June 2006 (UTC)
    • Well, you did say "to a doctor's level"... -- Миборовский 07:57, 23 June 2006 (UTC)
• I'll echo Jpgordon's comment and say that Gray's Anatomy is the unquestioned gold standard for anatomical reference texts. From the standpoint of actually learning the anatomy, you could try visiting your local medical school's bookstore and pick up some anatomical colouring books. (Forcing yourself to identify and colour every bit of the anatomy is one of many pedagogical tactics to aid memory.) Practice always helps—for every part of your body that you can see and reach, try to identify all the visible or tacticle bones, muscles, tendons, blood vessels, etc. It's even more fun if you can find a friend who will let you play doctor. :D TenOfAllTrades(talk) 23:00, 22 June 2006 (UTC)
• Video! Anatomy for Beginners. Before you read anything, it's best to have a visual understanding of what's inside the body. It's utterly fascinating. --mboverload@ 23:04, 22 June 2006 (UTC)

I would recommend the Anatomy Coloring book very strongly (ISBN 0805350861), the Physiology Coloring Book is great too.Tuckerekcut 01:21, 23 June 2006 (UTC)

You could try vivisection on yourself. Several mirrors and loads of sedatives are recommended for this method. DirkvdM 18:18, 23 June 2006 (UTC)

And industrial cleaning supplies. --Ginkgo100 ^{talk · contribs} 21:48, 23 June 2006 (UTC)

Thank you very much for the very informative and humorous comments  ;)

human diagram - showings measurements of age groups

Been searching 2 days for a really basic, HUMAN BODY DIAGRAM - showing measurements of body divisions. (as, theigh portion of leg.) Measurements divided into 3 major age groups, (child, teen, & adult)-

Thanks, Boswell --Boswell6 23:15, 22 June 2006 (UTC)

Is this what you wanted? [4] alteripse 23:54, 22 June 2006 (UTC)