Wikipedia:Reference desk archive/Science/2006 July 27

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[edit] Dizzy.

I'm really dizzy. I was watching a medical show on t.v. and I started to feel a bit dizzy, after I put my head up. I figured it was all in my head at first, because I was watching a medical mysteries thing. When the show was over, I turned off the t.v. and sat up. I felt alot more dizzy and began reaching for the remote to see what was going on. I felt really scard for some reason, and I wanted a light back on. I started sweating, mostly from fear. I thought a man was coming at me, but I am guessing this was only because the show was focused on night terrors ect. I went up stairs, I was very distraught and scared. I told my parents, and they said to go lay down and get a drink. So I went back down stair with my water, and laid down on the couch. I felt good again, until I got back up to use the washroom. I could barely finish my urination before I began feeling dizzy again. In fact I had to sit down immideiately after leaving the washroom because I could barely stand. I sat in the corner for a bit until I deceded that maybe they would be able to help me on wikipedia. So I walked up stairs, it was a bit easier than last time. I went on, still a bit dizzy (I am still dizzy) and now I am asking. I lookd under causes of dizziness, but I have a hard time matching my symptoms with the other sypmtoms listed. I am 5'10 and 120 pounds. I am underwieght but Not Anorexic or bulimic. I do use the computer alot. I have no history of epilepsy or anything like that. A few years back I did have a twitch in my eye, and I had brain tests done. For breakfast I had an all bran bar and water. For a snack I had chips and water. For supper I has two mcdonalds cheeseburgers. I drank a few bottles of water throughout the day, and went for a bike ride. I had a few msquito bites (I'm not sure about west nile symptoms or how quickly they appear) and I was by a campfire. I just realized a good example for my dizziness. It feels kind of like I just had a few too many cigarettes, but less stomach sickness and more dizziness. PLease answer ASAP I don't want to sleep really untill I find out whast wrong. And while we're talking about sleep, I only got about 5 hours of it last night, which might be a cause aswell, I don't know.

Oh my. Well, first off, Wikipedia is not a doctor's office. Maybe you could find the reason in our article on dizziness, which lists several causes, but if it continues or worsens you may want to see a doctor. Hyenaste (tell) 04:03, 27 July 2006 (UTC)
That being said, if you're in the northern hemisphere, it can get hot in the summer, and at least for me the most common cause of dizziness is dehydration. Try drinking some more water. --18.239.6.57 04:23, 27 July 2006 (UTC)
Yeah. Apart from general principle, you should definitely ask a qualified doctor about dizziness. It's such a vague symptom, and so common, and caused by such a wide variety of things(including sitting up too fast and, as you say, five hours of sleep), that that alone isn't nearly enough for a diagnosis. If it was more specific, like a bumpy rash or discolored fingernails, we could at least give good odds on something. Black Carrot 04:29, 27 July 2006 (UTC)
You didn't sign your posting, so I can't see what time you wrote this. But if you're in Europe, you're in the middle of a heat wave. The most threatening thing about that is dehydration because thirst is a bad indicator for that, so people don't notice they don't drink enough. You say things improved after you drank some water. Drink some more. And drink at least a few litres per day. See if that helps. DirkvdM 09:33, 27 July 2006 (UTC)

The most common causes of dizziness in teenagers are anxiety, orthostatic hypothension, and hyperventilation, none of which is dangerous. However, there are many other more serious causes. If it does not happen again do not worry about it, but if it recurs see your doctor. Also, get some sleep, get some exercise, and eat less McD. alteripse 11:34, 27 July 2006 (UTC)

Thanks, it turned out to be an inner ear infection. I went to the hosptial the next day.

Ouch. I had an ear infection a little while ago (albeit not an inner ear infection) so I know how much that can hurt. Hopefully you got the treatment in time before the pain got really bad. The dizziness makes sense for an inner ear infection because that's where the balance organ is. The Equilibrioception article mentions it as one of the causes. DirkvdM 06:14, 28 July 2006 (UTC)
Ditto. I've had the opportunity to experience it twice, and it was pretty horrible both times. And that, of course, is exactly why we aren't allowed to diagnose anything - not one person suggested that. Black Carrot 05:01, 29 July 2006 (UTC)
Yeah, but we can still try to help. We're instant (especially important at night, as in this case), for a doctor you have to make an appointment. Drinking water might have helped and it could hardly have hurt. DirkvdM 06:49, 29 July 2006 (UTC)

[edit] Rifle Bullets and Speed of Sound

If a 7.62 x 51mm NATO round breaks the speed of sound when fired from a rifle, why doesn't it hit a target soundlessly?

I have seen metal plates hit with rifle bullets, of this particular caliber especially, and it still goes 'BING'. Shouldn't it hit the plate soundlessly and then be followed by the sound of it hitting the plate a few moments later?

I came up with this question after noticing that when a bullet like this is fired from a rifle, the echo of the report is actually quite a bit behind the bullet actually making an impact against something, depending on how far away the shooter is, sometimes it is a whole second or more. So why doesn't it do the same thing for a target? Thanks, --69.138.61.168 05:06, 27 July 2006 (UTC).

The sound of it hitting the plate is produced.... when it hits the plate. That sound then propagates outward at its normal speed. The report is produced when the cap of the bullet explodes, and does, as you say, lag a bit behind the bullet. Black Carrot 05:13, 27 July 2006 (UTC)
(edit conflict) It doesn't really have anything to do with breaking the sound barrier; it's just a matter of where the observer is standing with respect to the events occuring. When the shot is fired, both sound waves (slow) and light waves (fast) start traveling from the barrel to your eyes and ears. Same thing when the bullet hits the target. If you're standing near the target, the time separation between sound and light for the impact might be too small to detect, but if you're far away from the shooter, you might be able to detect the separation for the report. The shooter herself ought to be able to hear separation for the sound of the target impact, but not for the report. This should all hold true regardless of the speed of the bullet. --Allen 05:15, 27 July 2006 (UTC)
The bullet carries its own sonic boom with it. Just as a little tidbit of info. — The Mac Davis] ⌇☢ ญƛ. 15:34, 27 July 2006 (UTC)
Really? So, if you were to fire a bullet at a sheet of glass, but miss, would the glass still shatter? Black Carrot 19:42, 27 July 2006 (UTC)
Sonic booms don't automatically break windows. They shake them. If it's a big boom they shake them a lot, and that might break them. A rifle sonic boom is not that big, so I don't think it will shake the glass very much. 71.199.123.24 21:17, 27 July 2006 (UTC)
Depending on the round, it can be big enough to blow your eardrums if fired too close to your ears. --Kainaw (talk) 00:17, 28 July 2006 (UTC)
Just as a further consideration, even though the muzzle velocity is above the speed of sound, the bullet may be going quite a bit slower than that depending on how far away the plate is, air density, etc. Matt Deres 14:25, 28 July 2006 (UTC)
I've tended targets on an 800m range where the shooters were using supersonic rifle ammo. The report from the shot was quiet compared to the sonic boom (of course, the report was nearly a kilometer away, the sonic boom - as Mac Davis said - is carried with the bullet. The sonic boom came noticably before report. --Polysylabic Pseudonym 10:28, 4 August 2006 (UTC)

[edit] Protein in Synovial Fluid

Can anyone tell me why there is a high level of protein in the synovial fluid?*****************************************AmberChoate

I'm no biologist, but it seems obvious that since the purpose of the synovial fluid is lubrication, it has to be made of thick, slippery proteins. —Keenan Pepper 20:03, 27 July 2006 (UTC)

[edit] Regardig child Hemoglobin

My baby (1 year and 3 months old) is suffring from problem of less Hb.i am working in cement factory. he stay with me for three months before this he was weak but active .but when he stayed with me in the factory area. he was told that suffring from less Hb. Now doctor gave hin three months therepy.

0n july 1-2006 Hb-7Gram Tcl   6000
on july 10-2006 Hb-8gram tcl- 4200 
on july 27-2006Hb-9gram Tcl   8900

Please tall me how much should be the Hb of child What are the best medicine to increase Hb. Is there ant relation about the bonemero to this if yes tall all. what should be the diet (vegitarian) to give the child . how to increase the quanity of milk.

Pl send reply on <e-mail address removed>

Pankaj kumar
solan (h.p.)
These would be great questions to ask your baby's doctor. — Knowledge Seeker দ 06:50, 27 July 2006 (UTC)

A 15 month old baby should have a hgb of at least 11 g/dl. Anemia at that age in North America is most commonly caused by iron deficiency related to high cow milk intake. The treatment is less milk and more iron. I know of no vegetarian iron source high enough to quickly reverse iron deficiency if that is the problem, but there are inexpensive pharmaceutical iron supplements. There are many other possible causes of anemia in a 15 month old, and I do not know the relative probabilities in south Asia. If the cause is not iron deficiency, then extra iron will not fix it. Thalassemia is a common cause of anemia in which the CBC might suggest iron deficiency but it would not respond to treatment. The rest of the CBC and a reticulocyte count would distinguish excessive blood loss or destruction from most causes of reduced production of red blood cells by the bone marrow. You do not tell us what "therapy" was given. Ask your baby's doctor these questions. alteripse 11:29, 27 July 2006 (UTC)

Dark green leafy vegetables like spinach, kale, and broccoli are good sources of iron, but it may be difficult to get a young baby to eat those things. The most common way to add iron to a baby's diet is with iron-fortified milk or cereals. --18.239.6.57 16:13, 27 July 2006 (UTC)

You need your doctor to give you a better diagnosis of your baby's anemia. Since you work in a cement factory, and the baby spends time there, it might be appropriate to wonder if he's eating clay, a behavior (pica) that can cause iron-deficiency. Your doctor should be able to tell you from the baby's blood test if it seems to be an iron-deficiency anemia or not. The hemoglobin seems to be getting better on therapy, but you don't say what that therapy is. - Nunh-huh 18:32, 27 July 2006 (UTC)

That isn't correct - the clay-eating pica is a symptom of iron-deficiency, not the cause. The most common cause of iron-deficiency is...deficiency of iron, as in not enough iron in the diet. --198.125.178.207 20:27, 27 July 2006 (UTC)
You're mistaken. Current literature is divided over whether pica causes iron deficiency or iron deficiency causes pica; it's certainly something to consider when a child spends his day surrounded by clay. - Nunh-huh 21:16, 27 July 2006 (UTC) (And, of course, the most common cause of iron-deficiency anemia is menstruation.) - Nunh-huh 21:18, 27 July 2006 (UTC)
If this is true, and you can find some citations to support it, please change the article on geophagy or pica to reflect the controversy. --198.125.178.207 21:38, 27 July 2006 (UTC)
Parry SD, Perkins AC, Hawkey CJ, "A case of pica and iron deficiency anaemia in Nottingham", Int J Clin Pract. 1998 Jul-Aug;52(5):354-5. "Current literature leaves uncertain whether pica causes iron deficiency via its proposed effect on iron absorption or, conversely, whether iron deficiency causes pica." - Nunh-huh 22:01, 27 July 2006 (UTC)

[edit] Pharmaceutical color coating

I was trying to understand the pharma color coating industry - what are the technologies that are involved and how is the whole process run...I am looking for color coating for tablets as well as caplets


Thanks Vikram

[edit] Synasthesia

Synasthesia is the condition by which different senses get 'confused', and (for example) sounds can appear as pictures. My question is: If someone experiences sounds as pictures, do they also experience the reverse? Would seeing what is normally the response to a high-pitched beep induce hearing a high-pitched beep? Or is it strictly a one-way phenomenon?

Thanks. —Daniel (‽) 13:15, 27 July 2006 (UTC)

Our article on Synaesthesia may be of some help. Note the spelling, also; it can be spelled synaesthesia, or synesthesia. Tuckerekcut 14:49, 27 July 2006 (UTC)
Synaesthesia is one way, I believe. It's also usually not as general as you describe. The most common form (as far as I'm aware) occurs when specific letters of the alphabet (and sometimes numbers, mathematical symbols for mathematicians, etc) are associated with specific colors such that if you present the person with an A, they will get the sensation of seeing, say, a light brown. If many years later you present A again, they will sense the same color. Multiple symbols may share the same or similar colors, but I don't believe it is usually the case that if you show them a particular color, the symbols associated with it will come to mind. In general there are a lot of different kinds of synaesthesia, so there may be a few rare individuals that would show the phenemona you describe, but the type I'm most familiar with (which isn't terribly familiar) is as I described. Digfarenough 22:20, 27 July 2006 (UTC)
I can say with relative confidence that synesthesia is indeed a more general shift from one sense to the other, but is equisitely variable from person to person. The accounts given in the article cited above do reference the stories of individuals who are effected in the way Digfarenough described, but I believe that this in an instance where wikipedia's article is not as comprehensive as it could be. It is notable that in many of the instances given for that article, the synesthesia is conducive to seeing various types of creative pursuits in new ways (an arguably beneficial set of cases). I am aware of some accounts (related to me personally) where individuals under the influence of certain chemicals could "hear" certain kinds of light, for example one individual claimed that flourescent lights sounded like buzzing insects and incandescent bulbs hummed pleasantly.Tuckerekcut 04:15, 28 July 2006 (UTC)

Thanks, all. Very interesting. —Daniel (‽) 20:27, 28 July 2006 (UTC)

[edit] Laurus nobilis, fertilization of

We have a potted bay tree, very young and small.

I want to know whether to use "all-purpose" fertilizer for it, or would "acid" fertilizer (that we use for potted citrus trees) be better?

(email removed)

(MaryAnn Salo)

We don't have any information on this in our Bay Laurel article, however a google search for "laurus nobilis" turns up a number of links that mention fertilization techniques but don't mention the use of citrus fertilizer. --Robert Merkel 17:57, 27 July 2006 (UTC)

[edit] Pauli's principle Pauli's exclusion principle

In a book, I found out that there is a difference between Pauli's principle is a little different from Pauli's exclusion principle. Is it true? I know in the article of Pauli, It is mentioned as the same thing. But please get it confirmed. I will be grateful to anyone who helps me.

Well, what does the book claim as the difference? Melchoir 16:20, 27 July 2006 (UTC)
I'm not familiar with a Pauli's principle. — The Mac Davis] ญƛ. 20:12, 27 July 2006 (UTC)

The Pauli effect was when Pauli was in town, experiments tended to go wrong! The Pauli Exclusion Principle is a quantum-mechanical effect. It states that no 2 electrons could occupy the same set of quantum numbers in a quantum orbital. Since electrons are identicle, the only difference would be their spin.

Actually, this not only applies to electron but to fermions, particles with half-integer spins. And the occupation not only applies to atomic orbital but to all quantum states.

[edit] science

What is the scientific mechanism that causes you to go blind when you masturbate?-Titanicalastic 15:43, 27 July 2006 (UTC)

There is no mechanism, it's a myth. Dragons flight 15:46, 27 July 2006 (UTC)

Alright so the mecahnism is supernatural not scientific, still, what causes it to happen?-Titanicalastic 15:57, 27 July 2006 (UTC)

God sees you, gets mad, and pokes your eyes out. --18.239.6.57 16:15, 27 July 2006 (UTC)
May we assume you haven't gotten around to trying this yourself? Black Carrot 19:40, 27 July 2006 (UTC)
Dude, you can masterbate all you want. Its fun. — The Mac Davis] ญƛ. 20:11, 27 July 2006 (UTC)
Come on, watch that spelling. Masturbating is so much more fun than masterbating. For one, it's spelled right. - Mgm|(talk) 22:30, 28 July 2006 (UTC)
A sub-question. Ages ago, some people on these pages asked questions about having trouble coming with a woman, and the answer some people gave was that they had experienced it themselves due to excessive masturbation with too firm a grip. Is this a real thing, and are there studies/cites? If so, shouldn't teachers mention it? Just a wonder. Skittle 22:18, 27 July 2006 (UTC)

You ask a question on the science ref desk and then exclude scientific explanations? DirkvdM 12:22, 28 July 2006 (UTC)

Ironically, if Oedipus had masturbated instead of boinking his mom, it might have prevented him from blinding himself. StuRat 19:25, 28 July 2006 (UTC)
Fictional, anecdotal, yet persuasive. Black Carrot 21:52, 28 July 2006 (UTC)

see http://en.wikipedia.org/w/index.php?title=Traumatic_masturbatory_syndrome&oldid=38061888

[edit] Cashew nuts healthy?

Are cashew nuts healthy? The article doesn't say. Thanks, Jack Daw 17:46, 27 July 2006 (UTC)

Well, they're high-caloric, so it's certainly not a good idea to eat too many of them; you'll get fat. Beyond that I don't know. Note that Wikipedia does not give medical advice, so I'm not too upset that the article doesn't say. --Trovatore 17:56, 27 July 2006 (UTC)
A quick Google search reveals some good information. Check out this site, for example. Maybe you'd be willing to add some of the relevant data to the cashew page? -- Scientizzle 18:32, 27 July 2006 (UTC)
Given that most naturally occurring food that has been eaten for thousands of years is perfectly healthy, I wouldn't expect the article to mention health, unless there were specific concerns about health. The article says it's a food, and food by definition is good for you, unless of course you're allergic to nuts.--Shantavira 18:35, 27 July 2006 (UTC)
see also Urushiol --GangofOne 19:46, 27 July 2006 (UTC)
Nothing is healthy or unhealthy, it is the dosage that is healthy or unhealthy. If healthy means edible, than cashews are edible. If you are looking for a low-oil food, than cashews are not a good choice. — The Mac Davis] ⌇☢ ญƛ. 20:05, 27 July 2006 (UTC)
You say nothing is healthy or unhealthy, and that only dosages are healthy or unhealthy. Well, it depends to what you are referring. As a blanket statement, it is patently false. There are not only things one can consume on earth that are unhealthy, but downright deadly - poisonous - that one would only know was unhealthy due to knowledge from the past experience of others. In addition, you mention nothing about the quality of a product (due to plant or animal rearing), as that can and almost always will affect said quality. - Andrew Taylor; 19:10, 06 March 2007 (PST)
There is a belief in my community that cashew nuts are healthy but the seed coat is not (it is supposed to be harmful, as is supposed to be the case with some other seeds too). See the section Sumac Family (Anacardiaceae) in http://waynesword.palomar.edu/ecoph1.htm. The article Urushiol may help. --Wikicheng 04:35, 28 July 2006 (UTC)
I once experienced that last bit when I ate a raw cashew nut. It hurt my mouth so much that I was really worried, but it doesn't seem to be a serious health hazzard. As for the fat, yeah too much of that is unhealthy, but that's a silly remark because too much of anything is unhealty. That's why it's called 'too much'. :) In the US there is a real anti-fat craze, which drove me nuts when I was there because I like fatty food. It's just a matter of balancing it with the amount of energy you burn and the other sources of energy like sugar, which food in the US seems to be full of, which I also hated. The only country that's worse for food is the Philippines, where you can only get hamburgers.
Oh, and nuts in general are healthy. DirkvdM 12:29, 28 July 2006 (UTC)
You must have been in the US a long time ago, the low fat fad was replaced by a low carb trend, specifically the Atkins diet. This craze died off after the fat author of that book dropped dead. I believe in eating healthy vegetable fats and limiting unhealthy animal fats (except for fish) and avoiding trans-fats completely. Hopefully this craze will catch on. But then again, I would likely have to pay $10 per avocado if it did. StuRat 19:11, 28 July 2006 (UTC)
I was in the US in the mid nineties, but the low-fat thing was so pervasive that I thought it was more permanent. Maybe you're talking about a relative change. Low-fat food may still be more popular than in Europe, but that's just guessing. DirkvdM 07:09, 29 July 2006 (UTC)

Any question about whether something is healthy brings up the question "as compared to what ?". As a primary source of protein and fats, most nuts, cashews included, are probably healthier than many other sources of protein and fat, such as meat and poultry, but probably not as healthy as fish (fish without mercury, that is), tofu, beans (for protein), or avocado (for fats). If compared to other nuts, then cashews are somewhere in the middle, with walnuts being perhaps the healthiest due to their high omega 3 fatty acids and macadamia nuts being perhaps the worst for their even higher total fat content. If compared with junk food, like potato chips, then cashews are a definite improvement. One thing to watch out for, though, is that nuts are frequently salted excessively, which makes an otherwise OK treat quite unhealthy, especially if you have to down a soda to compensate for all that salt. StuRat 18:58, 28 July 2006 (UTC)

A question almost everyone fails to ask is "Why is fish somehow good (when not contaminated with mercury) but land animal meats somehow so bad? Aren't they both natural meats?" The simple fact lies much in your reference to Omega 3 fatty acids in asserting walnuts are likely the healthiest of nuts. Omega 3 presence in meats is entirely subject to husbandry of the animals. The fish you refer to as being healthy is wild fish. All farmed fish has been shown to be just as bad as the ever-vilified beef. When put into an unnatural situation and fed an unnatural diet, the balance of omega 3 to omega 6 shifts drastically in the direction of the latter. Cows and chickens are not designed to eat grain. How would they in a natural setting? They are meant to eat grass, and in the case of chickens, perhaps some bugs as well. It has been shown that animals with such a diet (often called "grass-fed") have equivalent if not near equivalent levels of omega 3 as wild fish. -- Andrew Taylor; 19:10, 06 March 2007 (PST)

Cashews and pistachios, as well as poison ivy, poisonoak, poisonwood, and sumac are in the family anacardiaceae. Many people have extreme allergic reactions to many mambers of that plant family. [[] 00:00, 31 July 2006 (UTC)protogeek

[edit] nephrology laboratory terminology

how would you write out 381 mg per gram of creatinine in a scientific formulation?

First of all, we would need to know 381mg of what per gram of creatinine? Rockpocket 20:22, 27 July 2006 (UTC)
Biological exposure indices are often given in terms of "mg/g creatinine". I'm not quite sure what you mean by "scientific formulation"; in words, it's "381 milligrams per gram of creatinine"; abbreviated, it's "381 mg/g of creatinine". In a nephrology lab, you're probably measuring albumin to creatinine ratio as a measure of nephropathy? So "381 mg albumin per gram of creatinine".... or "an albumin/creatinine ratio of 0.381". - Nunh-huh 21:13, 27 July 2006 (UTC)

[edit] prada willy syndrome

Can you direct me to any info on this?? I can't find anything on Google.°

David

It's a joke - at least according to this blog. It says "Prada Willy Syndrome: A disease where women are not interested in a man's willy unless he can keep her in Prada." --198.125.178.207 20:43, 27 July 2006 (UTC)
See Prader-Willi syndrome Richard Taylor 21:06, 27 July 2006 (UTC)
LOL - nice work Richard - is that what you were looking for David? --198.125.178.207 21:08, 27 July 2006 (UTC)
Is it any coincidence that there was a documentary on Channel 4 about this one hour ago!? Iolakana|T 21:47, 27 July 2006 (UTC)
LOL, spelling is so important. Sorry but I can't help point out the corollary: what we might call vagina-hamburger sydrome.--Shantavira 06:59, 28 July 2006 (UTC)
  • This just happened to be on Dr. Phil one or two days ago in the Netherlands. Can't be a coincidence. - Mgm|(talk) 22:28, 28 July 2006 (UTC)

[edit] Sound and Wind

This may seem like a silly question to you, but to me it's a pretty darn good one. Anyways, I was outside recently during a thunderstorm (putting away things that shouldn't get wet) when I saw a flash of lightning. Suddenly, the wind picked up and then thunder came. A few seconds after the thunder ended, the wind died down again. This leads me to my question: can sound waves (such as the ones caused by lightning/thunder) increase wind speed? Thanks --71.117.41.30 20:41, 27 July 2006 (UTC)

I don't know, but I tend to doubt it. It doesn't seem like a lightning strike should kick up wind in any single direction, and it wouldn't be able to blow purely outward either, because the air has to come from somewhere. That leaves the possibility of forming a convection cell, which I guess is plausible since the lightning does dump heat into the air. But enough heat to form a cell a few miles wide?
Either way, I wouldn't point my finger at the sound waves, since a wave alone doesn't displace much material if any. And if the wind picked up before the thunder reached you, then the advancing thunder would have had to launch a supersonic wind, and that just causes all manner of logical problems. Melchoir 21:01, 27 July 2006 (UTC)
No - I'm pretty sure that was just a coincidence. The thunder is a sound wave created by the violent sudden heating of the air near the lighning bolt. If you look over that article on sound waves, you should see that sound waves are propagating pressure variations, so when you hear the thunder, in a loose sense, that is the "wind" from the lightning - any other wind is just a coincidence. --198.125.178.207 21:04, 27 July 2006 (UTC)
Wind is a permanent displacement of air. A flash of lightning also displaces air, but it does that for a very short period. After that, the driving force disappears and leaves a vacuum where the air first was, so it moves back again. This causes a wave with a very short wavelength, which is called sound and in this case thunder. DirkvdM 12:35, 28 July 2006 (UTC)
Here's some speculation. Thunderstorms are powered by the fall of electrically charged raindrops, and this makes the raindrops fall more slowly. (They slow down because they are charged negative, and are being attracted by a region of positive charge above.) But immediately after a lightning flash, the large region of positive charge within the storm cloud is lessened. Until it builds up again, the raindrops will fall more rapidly. And finally: raindrops drag a region of air along with them as they fall, so as the rain speeds up after a lightning flash, the wind should pick up too. --Wjbeaty 17:23, 28 July 2006 (UTC)
On a variation of the above theory, the sound waves may force water particle in the air together to form drops large enough to fall, thus "dragging some air along with them". This would create a downdraft which would eventually spread out as wind. I doubt if this would be a very noticeable effect, compared with wind from other sources, however. StuRat 18:44, 28 July 2006 (UTC)
The sound wave is like a water wave, the particles in the air's displacement is theoretically zero. In a water wave, water molecules are moved up, then down, by energy, because a wave is just moving energy in a medium. Ideally, everything is put back where it was. A concussion caused by say, a nuclear bomb, will move things, but a sound wave is really more like a boost mode for a short time, then the particles move back to where they were. Ever listen to loud music? If you put your hand on top of a woofer you can feel the air being pushed out, and back in again, because the speaker, if you imagine your headphones for instance, the membranes, no matter how far they move and push air out, they always return to their original position and suck that amount of air back in. — The Mac Davis] ญƛ. 18:10, 28 July 2006 (UTC)
A concussion caused by a nuclear bomb would probably be pretty severe. :) DirkvdM 07:14, 29 July 2006 (UTC)

[edit] Stiches and Nosebleeds

what is the best way to stop stitches and nosebleeds? thanks --86.130.255.231 20:45, 27 July 2006 (UTC)

Not sure why you would need to stop a stitch, but here are some nosebleed treatments. Hyenaste (tell) 20:51, 27 July 2006 (UTC)

as in a stitch that u get after running for a long time --86.130.255.231 21:11, 27 July 2006 (UTC)

There is a surprisingly comprehensive article on the side stitch, which gives some possible treatments. Also, a more general article on cramps could be of use. --198.125.178.207 21:31, 27 July 2006 (UTC)
My sports teacher said the best cure was to keep on running. Not sure if he was a sadist. I do vaguely recall it helped, though. DirkvdM 12:38, 28 July 2006 (UTC)
lol, that's the "Just ignore it" treatment. Eventually it would stop anyway, and it may have provided the illusion that continiously running would fix it. — The Mac Davis] ญƛ. 18:11, 28 July 2006 (UTC)

As for stopping nosebleeds, roll up some tissue and put it up the nostril in question to absorb dripping blood until it scabs over. To avoid noseblleds in the future, keep the nostrils moist with a spray bottle or vaporizer. This should allow you to blow your nose instead of picking it. Also note that frequent nosebleeds can be signs of more serious health problems, like high blood pressure. StuRat 18:38, 28 July 2006 (UTC)

Taking the small sample of my family (5), we all had a tendency to nosebleeds at about the age of 14. Those who used Sturat's technique continue to have them into their 20s, those who applied outside pressure and cold until it stop ceased having them in a year or two. The GP was very cross when told the technique the younger brother was using (Sturat's) as it seemed to stretch stuff in his nose and increase his tendency. Just a head's up. But it is a very small sample. Skittle 18:04, 29 July 2006 (UTC)
For stitches, a preventative method is too breathe in a fixed rhythm (ie in in out out). If you concentrate on it you rarely get them. —Daniel (‽) 20:23, 28 July 2006 (UTC)

[edit] billion

how many zeros in a trillion

In ordinary arithmetic the answer is undefined, but there are other possibilities. See division by zero. --Trovatore 21:11, 27 July 2006 (UTC)
I think the question referred to the number of occurrences of the numeral zero in the base ten representation of the number one trillion. The answer is...found in the article names of large numbers. The answer actuallly depends on the culture- in the US, it's 12 zeros. In the UK, it's 18 zeros. --198.125.178.207 21:22, 27 July 2006 (UTC)
Haha, great answer, Trovatore! —Keenan Pepper 01:41, 28 July 2006 (UTC)
It's abit more complicated than that. The large numbers article says the English used to use trillion for the 18 zeroes, but have started to adopt the American system. I had wondered before about the logic of the systems used in English and in Dutch (and other languages). The large number name sequence (and the SI prefix sequence) works with powers of 1000. So it would make sense to use the word 'one' for thousand (to the power one), 'two' for thousand to the power two, etc. In stead billion (two) is used for 1.000 to the power three in English and thousand to the power four in Dutch. But now I see in the article Long and short scales that the Dutch system uses powers of one million. So billion means million to the power two and trillion means million to the power three. Odd that I hadn't noticed that before. The powers of thosuand in between are designated with the ending ard (so million - millard - trillion - trillard, etc). But in English it's a bit more complicated. There powers of thosand are used (which seems better), but you have to add one every time (which is not good). So trillion means thosand to the power three plus one.
I hereby propose a new system, based on the word thousand. bisand is then 10002, trisand is 10003, quadrisand is 10004, etc. Only thou is no word for one, but I don't want to stirr things up too much. :)
Then again, it can be simpler still. Why not simply use 'Kilo' for thousand, 'Mega' for million, etc. That would unify the two system (numbers and prefixes). DirkvdM 17:10, 28 July 2006 (UTC)
That brings up an old question of mine, why isn't there a metric system for time ? While admittedly the number of days in a year won't be an even multiple of 10 until we can strap some rockets on the Earth to change it's rotation and or revolution rates, there's no reason why subdivisions of a day or multiple years can't use metric prefixes. I guess we've just used the current silly system for so many kiloyears we just refuse to spend even a milliday considering alternatives. :-) StuRat 18:31, 28 July 2006 (UTC)
We do use kyr, Myr, Gyr. On the other end, ms, μs, ns, are also fine. It is only the junk in between that isn't very metric. Dragons flight 18:40, 28 July 2006 (UTC)
See Decimal time and Metric time. --Serie 18:46, 28 July 2006 (UTC)
I love how some guy's random question evolved into the reinvention of numbering M@$+@ Ju ~ ♠ 00:00, 29 July 2006 (UTC)
I've proposed some solutions to that too, on my user page: User:DirkvdM#Time. I seem to have an answer to everything. :) DirkvdM 07:26, 29 July 2006 (UTC)
We seem to be in total agreement on this issue. This is evidence that I apparently must now be clinically insane, as well. :-) StuRat 07:53, 29 July 2006 (UTC)
Join the club. It's a very small club. You're number two. I'm no longer unique! DirkvdM 19:06, 29 July 2006 (UTC)

[edit] UV lightbulb vs. UV light bulb

I am a technical editor and I was corrected by a scientist when I tried using "UV lightbulb" instead of "UV light bulb". Since "lightbulb" by itself is a single word, why is UV light bulb different? Convention?

Thanks for the help.

Lorin Fischer

I think "light bulb" is a more common usage for all types, UV or otherwise. It seems that "lightbulb" is acceptable. "light bulb" always seems to be the primary punctuation, for instance in our wikipedia article on Light bulb, and at princeton's online lexical tool. Could be wrong, though --198.125.178.207 21:28, 27 July 2006 (UTC)
It might also be that UV specifically needs to modify the word "light" in his/her mind (it is not a lightbulb which emits UV, it is a bulb which emits UV light). But I don't know, it sounds like a pretty pedantic distinction to me. --Fastfission 01:31, 28 July 2006 (UTC)
As has been mentioned, "light bulb" is more common that "lightbulb" (see this highly unscientific googlefight) but unless there's a good reason it's really just a matter of the publisher's style - for example, The Guardian's styleguide[1] calls for the use of "lightbulb". -- AJR | Talk 12:05, 28 July 2006 (UTC)
I would think that a lightbulb would be the incandescent lightbulb, where as light bulb would mean that light is describing the bulb. "Light" as in weight/mass, value (shade), or if it was literally made of photons. Therefore, lightbulb. — The Mac Davis] ญƛ. 18:13, 28 July 2006 (UTC)

Note that while questions about how light bulbs work belong here, grammatical questions about the usage of the word belong on the Language Ref Desk. StuRat 18:22, 28 July 2006 (UTC)