Wikipedia:Reference desk/Archives/Science/2012 August 4

= August 4 =

Farts
Not trolling—is it possible to fart in your sleep? 71.146.0.138 (talk) 01:26, 4 August 2012 (UTC)


 * I would assume so based on the various TV shows with characters farting in their sleep. Futurist110 (talk) 01:48, 4 August 2012 (UTC)
 * Does this count as original research? Yes.  I've been told I do it all the time. Mingmingla (talk) 01:50, 4 August 2012 (UTC)
 * Thanks. 71.146.0.138 (talk) 03:49, 4 August 2012 (UTC)
 * Flatulence is caused by the buildup of gases in your gastrointestinal tract, usually as byproducts of secondary digestion by your gut flora. Their movement down your intestines is also controlled by the peristaltic movement of involuntary smooth muscles, which does not depend on you being conscious. So yes.-- O BSIDIAN  †  S OUL  03:40, 4 August 2012 (UTC)
 * Thanks. 71.146.0.138 (talk) 03:49, 4 August 2012 (UTC)
 * Thanks. 71.146.0.138 (talk) 03:49, 4 August 2012 (UTC)

The most common thing to wake me on long car trips where I am not driving is the rush of air as the windows are rolled down in panic. My grandmother's favorite story was of the woman from the next county over who, when looking for the pepper at the church kitchen while cooking pierogies on a Sunday, instead of asking, Gde póper déla? with a fixed Polonic penultimate accent asked Gde popér(-)dela? with a free Ukrainian oxytonic accent. μηδείς (talk) 05:13, 4 August 2012 (UTC)
 * As a non-speaker of Polish or Ukrainian (aplogies for this lamentable deficit) I'd be quite interested in understanding this semantic joke, any chance of a translation? Richard Avery (talk) 06:49, 4 August 2012 (UTC)


 * Certainly. The past tense of East Slavic verbs is formed by the past participle, which is declined for gender and number, with an implied form of "to be" which is usually deleted.  (English retains the archaic perfect forms "Christ is risen" and "The time is come" which are parallel, except that East Slavic drops the "is" as implied.  French has Elle est venue, "she is (has) come", with the feminine past participle of venir, "to come") The past participle of delati "to do, to put" for women is delala, shortened by haplology to dela.  (One generally adds -la to the verb stem to form the Slavic feminine past participle.)  "She put the pepper on the table" is Wona de(la)la poper na stol.  The verb perdeti, "to fart", (perd-, following Grimm's Law, is cognate to the English; the root is PIE) like many verbs, takes the prefix po- to imply a single, completed action, as opposed to a continuing action: poperdeti, "to make a fart" whose feminine past participle is popérdela.  Hence, the only difference between "Where did she put the pepper?" Gde póper déla and "Where did she fart?" Gde popérdela? in my grandmother's dialect is one of where the stress falls.  Her friend's dialect, however, had a different stress pattern, where poper was stressed on the final syllable, as opposed to most of the ladies at the church who pronounced the word póper with initial stress.  Hence their humorous reaction to her innocent question. μηδείς (talk) 07:26, 4 August 2012 (UTC)
 * :-) Thankyou. Richard Avery (talk) 14:10, 4 August 2012 (UTC)

Race and Running Speed?
This is a serious scientific question. I'm not trying to be offensive or racist. I've noticed that there are a lot of black people in professional (such as Olympic) running events. I have two questions:

1. Is the % of black people in professional running events disproportional to their % of the population? 2. If this is disproportional and a favorable proportion to black people, do black people have a genetic ability to run faster?

Thank you. Futurist110 (talk) 01:55, 4 August 2012 (UTC)


 * East Africans in particular, right? —Tamfang (talk) 02:46, 4 August 2012 (UTC)


 * Well, skin colour isn't going to make any difference at all. And different groups of people from many parts of the world have black skin. I doubt if the OP was thinking of Australian Aboriginals, Polynesians and south east Asians when he wrote that question. Some groups of people seem to have a higher proportion of members who can sprint faster than many (West Africans), or run longer distances better than others (East Africans), but one has to take social, geographic and economic factors into account too. If you live in a poor country, you're more likely to choose running as a sport than swimming or equestrian. If you live at high altitude, you can have an advantage in endurance sports. HiLo48 (talk) 03:04, 4 August 2012 (UTC)

See Kalenjin_people. Members of the Kalenjin tribe of Kenya win about 40% of marathons world-wide. μηδείς (talk) 04:56, 4 August 2012 (UTC)

By black, I meant the U.S. census definition of black, meaning of Sub-Saharan African descent. Futurist110 (talk) 06:29, 4 August 2012 (UTC)


 * And HiLo pointed out that having black skin itself is irrelevant to running, it's probably only a chance marker (for US Americans...) for a certain genetic, cultural, geographic and economic background that is relevant. Black skin is as relevant to running as is white skin to building high skyscrapers. The two things simply have nothing to do with each other causally, they are only associated by common economic, cultural and educational traits (that for example favor "white" architects to build many skyscrapers). --TheMaster17 (talk) 07:48, 4 August 2012 (UTC)


 * So you're saying it has to do more with lifestyle and exercise and that it has nothing to do with race? Gotcha. Futurist110 (talk) 07:56, 4 August 2012 (UTC)
 * HiLo: Sources please. And scientific ones for this Science desk, not social commentary. Rmhermen (talk) 14:07, 4 August 2012 (UTC)
 * Sources for what? If we demanded sources for everything posted here this would be a very different place. I'm not trying to deceive anyone. I just can't be bothered hunting down sources right now. Ignore my comments if they don't fit your belief structure. HiLo48 (talk) 18:11, 4 August 2012 (UTC)

There was a BBC Horizon documentary about this issue quite some time ago about the long distance runners from Kenya and Ethiopia. The conclusion was that the most relevant factor here was that these runners have longer legs in relation to the rest of their body (or certain parts of their legs are longer), and that means that for the same effort they will go faster. It is basically the same reason that explains why bipedal motion is more efficient than walking on 4 legs. A human can outrun a horse on the long run, hunter gatherers in Africa run for hours persuing antilopes eventually catching up with them...

For the sprint the type of muscles tissue you have is important, apparantly people of West African ancestory have the right stuff. Social effects can't be of much relevance here, because of the huge gap between the best white 100 meter personal best and the average best season's best time over the last decade. Only one white athlete has ever run faster than 10 seconds and none of the athletes from East Africa or Asia, see 10-second barrier:

"Nearly all the sprinters who have beaten the 10-second barrier are of West African descent. Namibian (formerly South-West Africa) Frankie Fredericks became the first man of non-West African heritage to achieve the feat in 1991 and in 2003 Australia's Patrick Johnson (who has Irish and Indigenous Australian heritage) became the first sub-10-second runner without an African background.[5][6][7][8] Frenchman Christophe Lemaitre became the first white European under ten seconds in 2010 (although Poland's Marian Woronin had unofficially surpassed the barrier with a time of 9.992 seconds in 1984).[9] In 2011, Zimbabwean Ngonidzashe Makusha became the 76th man to break the barrier, yet only the fourth man not of West African descent.[10] No sprinter of predominantly Asian or East African descent has officially achieved this feat."

Count Iblis (talk) 15:46, 4 August 2012 (UTC)


 * Keep in mind as well that you are talking also about the very bleeding edge of the bell curves, here. The bell curves for all populations in terms of running performance are going to look nearly identical; where they vary are going to be maybe tiny, almost imperceivable shifts in the median, and tiny, tiny differences on the far fringes. The Olympics and whatnot are pitting the far fringe of one country against the far fringe of another. The tiniest of differences in genetics, training, and so forth make the differences in such situations. The lesson here isn't that the population genetics don't matter for these sports — they do seem to — but that you shouldn't read racing performance (or sports in general) as telling you too much about population genetics. It is not likely the case that your average Ethiopian is genetically a better long-distance runner than, say, your average Swede, but over a large population of Ethiopians and Swedes, your handful of gifted Ethiopians will be better at this sport than your handful of gifted Swedes. (It is also obviously the case that the countries that spend more time and more money on searching out talent end up with more of it. There is likely no genetic reason that Americans, Russians, and Chinese dominate gymnastics and Africans do not — finding and cultivating gymnastic talent is just a much bigger deal in the former countries, so they are able to find those who reside at the end of the bell curves and devote enough resources to them that they go to the Olympics as opposed to doing other things with their lives.) --Mr.98 (talk) 17:48, 4 August 2012 (UTC)


 * In terms of long distance running again certain people from East Africa have a slight advantage - hence the dominance of Ethiopeans, Somalis and Kenyans in these competitions - they tend to have longer heel bones calcaneus than most other people. This difference gives then a slight leverage advantage to the transfer of power frome their achilles tendon's to the ball of the foot - in long distance races this small advantage adds up to result in a disproportionate number of marathon champions. (The same leverage advantage comes into play with Maasai men's traditional jumping dances.) Roger (talk) 18:26, 4 August 2012 (UTC)


 * I missed where Futurist attributed running speed to skin color. Has anyone ever heard of the Kalenjin people, who win 40% of marathons world wide?  I wonder what percentage of the world population the Kalenjin are?  Something near 40%?  Nothing statistically improbable going on there.... μηδείς (talk) 21:22, 4 August 2012 (UTC)
 * See second paragraph of first post. HiLo48 (talk) 00:14, 5 August 2012 (UTC)
 * The user is American, I expect he would have said races with dark skin if he had been referring to Australian Aborigines or other dark skinned races, and given his clarification, I think my expectation was correct. μηδείς (talk) 18:12, 5 August 2012 (UTC)
 * I guess I missed the part where anyone here claimed that the genetic and social opportunity were equally distributed. Fighting strawmen with strawmen is a waste of everyone's time. --Mr.98 (talk) 21:34, 4 August 2012 (UTC)
 * So your point is that the Kalenjin are pampered rich brats? This is the wikipedia reference desk.  If you think this place is about arguing you are mistaken.  Provide links and refs, not ideological OR and ad hominem. μηδείς (talk) 22:19, 4 August 2012 (UTC)
 * Are you just trolling? Because you don't seem to be addressing anything I — or anyone else here — has actually written. --Mr.98 (talk) 02:03, 5 August 2012 (UTC)
 * Everything you have provided above is OR, Mr.98. I'd love to see your graph of Inuit vs Kalenjin running ability.  Talk about straw men, as for "social opportunity", what are you on about?  The 1% and how they monopolize running shoes while the barefoot rest of us can't afford the price of running down the street, perhaps?  Who brought that issue up?  Was there a paragraph on it I missed in the Kalenjin article? μηδείς (talk) 18:12, 5 August 2012 (UTC)
 * "Social opportunity" just means the fact that they have folks who search out the talent and put them in there. It's a necessary prerequisite, obviously, to getting to any competition. Again, I don't think you're actually reading anything anyone else writes with the intention of making sense of it — which is a pretty good sign of a troll. What you get out of it, I'm not sure, but feeding you probably isn't going to help much. (My stuff isn't OR, it just isn't cited. I could awash you wish boring academic books about sensible ways for thinking about the biology and sociology of race, including books on sport and race in particular, but why bother? You aren't going to read them; you can't even be bothered to read posts on here that are contrary to your pre-held beliefs.) --Mr.98 (talk) 15:12, 6 August 2012 (UTC)

Body build is also important, for long distance running your BMI has to be very low while you can still eat 5000 Kcal/day or more. Take e.g. Mo Farah, his height is 1.75 m but he only weighs 56 kg. Many people from East Africa have this type of "walking skeleton" body build. Count Iblis (talk) 19:27, 5 August 2012 (UTC)

Usain Bolt says that the Jamaican food that he eats makes him run fast. Count Iblis (talk) 15:23, 6 August 2012 (UTC)

Neurology and music
Is there any neurological basis to the moods associated with different types of musical scales, or is it entirely cultural? --108.206.7.65 (talk) 01:59, 4 August 2012 (UTC)


 * See Cognitive neuroscience of music.—Wavelength (talk) 02:36, 4 August 2012 (UTC)
 * That article doesn't discuss my question specifically. --108.206.7.65 (talk) 17:37, 4 August 2012 (UTC)
 * Can you perhaps elaborate a bit on what prompted the question ? Do you think there are different moods associated with different types of musical scales and if so what are they, for example ?  Sean.hoyland  - talk 17:51, 4 August 2012 (UTC)
 * For example, major scales are associated with positive emotions while minor scales are sad. --108.206.7.65 (talk) 17:16, 5 August 2012 (UTC)
 * This Nature article and it's sources may interest you. And there are these articles about the minor third and sadness in speech (for speakers of American English).  Sean.hoyland  - talk 17:49, 5 August 2012 (UTC)


 * It certainly must have a cultural dimension, as listening to squealing Chinese music must be more pleasant for them, or they would have executing all of the musicians long ago. StuRat (talk) 03:36, 4 August 2012 (UTC)


 * The short answer is that yes, there are absolutely strong innate underpinnings to the emotional influence of certain tones, chords, prosody, and many other features of music, many of which are universal across cultures (in neurologically healthy individuals, anyway). Though of course culture does have some influence at the same time.  If you're interested in exploring this concept in depth, but want something that is (fairly) accessible to a non-cogntive-science-expert, then I can very strongly recommended both Daniel Levitin's This is Your Brain on Music and Oliver Sacks' Musicophilia.   If memory serves, Steven Pinker also treats the subject, albeit much more briefly, in his books How the Mind Works and The Blank Slate, which are great reads in any event. If you're looking for something especially light, I stumbled across a documentary sometime back called How Music Works which, from what I saw, seemed to put a good deal of examination into this subject as well, but I did not watch it at length.  I believe it was a BBC production, but don't hold me to that. Snow (talk) 03:57, 5 August 2012 (UTC)

Hydrotriiodic acid
Since hydroiodic acid contains the iodide ion, I don't see why combination with elemental iodine should not produce the triiodide ion as with iodide salts.--Jasper Deng (talk) 04:10, 4 August 2012 (UTC)
 * http://pubs.acs.org/doi/abs/10.1021/j100810a041 207.224.43.139 (talk) 05:48, 4 August 2012 (UTC)

Involuntary Change of Sexuality?
I know the one's sexuality is not a choice, but is it possible in extreme cases for one's sexuality to (somewhat) change over time due to factors out of this individual's control? For instance, could it be possible for a bisexual gay who initially strongly preferred women when it came to sexual attractiveness to strongly prefer men later on? Personally, I was always straight, but the characteristics and types of women that I found attractive have changed over the years. My question is if it is scientifically possible for such a change in one's view of sexual attractiveness to be much more extreme over the years, as in my example above? Futurist110 (talk) 07:35, 4 August 2012 (UTC)


 * That's a minefield of a topic. See Sexual orientation for a brief and extremely simplified overview; and the Kinsey Reports and the Klein Sexual Orientation Grid for two studies which have attempted to find out. But the answer is yes from the results of the Klein Grid and from personal observation.


 * The why, however, is problematic. It may be prison sexuality, latent bisexuality (in the traditional sense or the innate bisexuality sense), situational sexual behavior, coming out or finally accepting repressed homosexuality, self-enforced conscious rejection or adoption of an orientation (however ineffective that may be), experimentation, peer pressure, the result of personal trauma, positive or negative reinforcement over long periods, dissonance between gender and very strong emotional attraction (affectional orientation), hormonal, genetic, cultural, etc. Add to that the questions surrounding gender and sexual identity, and the religious and cultural conventions that attempt to control or classify them, and you end up with only one conclusion:


 * Sex is complicated.-- O BSIDIAN  †  S OUL  09:51, 4 August 2012 (UTC)


 * Tom Robinson describes himself as "a gay man, who happens to have fallen in love with a woman". Go figure. --TammyMoet (talk) 12:28, 4 August 2012 (UTC)


 * I am not sure about the issue of control (who would say their sweet tooth is voluntary?) but I can attest that my polarity, for lack of a better word, has varied over the years. Before I knew what sex was I had crushes on males and females.  From puberty to 18 I was primarily homosexual.  From 18 to 24 primarily heterosexual in action, and homosexual in dreams.  (My boyfriends and girlfriends have always known I was bisexual.)  Then the reverse.  Then back again after some time.  I must say, the most shocking development was when I dreamt of having sex with Britney Spears.  (And this was even after the South Park episode.)  She is not at all my type physically or musically.  But it was a dream, and I don't blame myself for acts of my subconscious.  (And it was fun!) I can offer no explanation.  But I recommend everyone try both ways lest they never know what they are missing. μηδείς (talk) 21:19, 4 August 2012 (UTC)


 * The recent scholarly history on this subject has presented an interpretation of sexuality as a largely innate (and to a large degree unalterable) psychological/cognitive feature. This trend, perhaps unsurprisingly, co-evolved with increasing social tolerance for, and understanding of, LGBT drives, and the overturning of the previous reigning paradigm that gay and lesbian desires were almost entirely learned (and thus "correctable".   Even more recently, however, some researchers are starting to question whether we may have over-corrected a bit might not be a bit more of a spectrum or "continuum" in which some (though certainly not all) individuals may have the propensity to slide from one category of sexual preference to another over the course of their lives, or under certain circumstances.   This view is slowly gaining some traction in terms of research geared specifically towards human neurology, but it's worthwhile to note that this interpretation of sexuality in many social species has been uncontroversial for some time.   All of that being said, there is at least some degree of innate preference in the vast majority of individuals and we're starting to understand the developmental mechanisms that go into forming them a bit more.  For example, it's now fairly well-established fact that men who were born as the third son or on are markedly more likely to self-identify as gay upon reaching sexual maturity (even adjusting for social home life during upbringing; that is, whether they were raised along side those siblings or not).  The popular explanation for this phenomena being that somehow the hormonal influence of past pregnancies somehow influences the development of these males in utero to result in children who (in our past evolutionary context) would have been able to assist their siblings in raising their progeny (who would share at least some of their genes, afterall), without further straining the demand on limited resources with their own offspring or becoming competitors for limited mates.  This is just one of many small but convergent facts that point to innate biological mechanisms influencing sexual preference long before the cognitive machinery is up and running to directly make these "choices".   But then there are some who, as they mature, will bounce back and forth between these preferences - Medeis' seems to be one such, from his description.   Honestly, most modern researchers are not likely to be surprised by this, I would think -- the concept of malleability, but only within certain constraints, is a pretty common refrain in a number of different sub-disciplines of the cognitive sciences these days.


 * All of this deserves one big caveat though -- while a small proportion of people may change their predilections over the course of their life, all research on the idea of "triggering" such a change suggests that, by and large, it cannot be done; that is to say Conversion therapy and similar methodology for "forcing" a gay person straight (or, theoretically, vice-versa) will have no substantive effect (unless perhaps that person's neurobiology was already swinging them into that new state).   Needless to say, many of the findings presented above are highly contentious (and as Obsidian noted, subject to interpretation via context), but I've tried to synthesize and represent the currently most common views by scholarship on the issue.   As regards the concept of a sexual orientation spectrum that I opened with, there has been a fair amount of both speculation and research in the last couple of years in particular and I'll see what I can't do about re-locating some of it for you. Snow (talk) 03:42, 5 August 2012 (UTC)

I just want to take clear--the change in sexuality has to occur naturally without a person wanting it. Futurist110 (talk) 07:36, 5 August 2012 (UTC)
 * That is actually not clear at all. There is a difference between something that is not voluntary, and something that is against one's wishes. μηδείς (talk) 23:33, 5 August 2012 (UTC)
 * Just see Sexual_orientation. 112.215.36.172 (talk) 10:09, 5 August 2012 (UTC)

Getting wet
It is raining. The rain is coming at me at 45 deg. I have no raincoat. Will I be dryer when I get home if I run through the rain or if I walk? --89.243.128.176 (talk) 14:04, 4 August 2012 (UTC)
 * If it's coming towards you, then running will result in less water falling on you. If its hitting your back, walk at the same speed as the rain is moving horizontally.-- Gilderien Chat&#124;List of good deeds 14:05, 4 August 2012 (UTC)
 * I agree with the first part, and in the second part, that strategy will indeed minimize the rain hitting you from the side, but it depends on the vertical velocity of the rain whether that is more important than minimizing the time rain is hitting you from above, which you would get from running as fast as possible. - Lindert (talk) 14:19, 4 August 2012 (UTC)


 * There was actually a recently released study on this in the European Journal of Physics. (See news coverage, , and freely available research article ). The short answer is that you'll be drier in almost all cases if you run instead of walk, although there are exceptions. -- 71.35.119.233 (talk) 18:14, 4 August 2012 (UTC)


 * Is it just me or has this all ignored the fact that if you run home, you spend less time in the rain? Yes, you may make complicated alterations to the raindrop-per-second rate and those are interesting deductions. But as long as rain is subject to gravity, you're going to be dryer for having spent less time in it. BigNate37(T) 18:48, 4 August 2012 (UTC)
 * Indeed. I expect everyone knows from personal experience that you can avoid getting as wet by running home. If you have to be outside for a fixed period of time, then all of this might make a difference, but if you can get home in half the time, you'll be drier. It's important not to over-think problems! --Tango (talk) 19:09, 4 August 2012 (UTC)
 * In a first approximation, speed doesn't matter. You have a certain density of raindrops in the air, and if you cover a certain distance, you will sweep out a certain volume (cross section times the distance covered), and that volume contains a certain amount of water. Count Iblis (talk) 19:37, 4 August 2012 (UTC)
 * We're not ancient Greeks - we don't ignore empirical evidence in favour of pure reason. We've all been caught out in the rain and know what happens. If you run, you don't get as wet. If your reason doesn't fit with the empirical evidence, they your reason is wrong. Now, it is possible that I'm simply wrong as I get just as wet either way - there is a natural human tendency to overestimate the amount of control we have over our lives. The way to find out isn't with maths, though. It's with people running and walking in the rain and seeing what happens. --Tango (talk) 20:38, 4 August 2012 (UTC)
 * Actually I think Count Iblis's approach is the best way of visualizing this problem, but you need to think of it in the rest frame of the raindrops, not the rest frame of the street. If the raindrops are falling at a 45° angle downward and to the right, then with respect to their rest frame, you, the street, and the shelter you're trying to reach are all moving at a 45° angle upward and to the left:

.........._........                   ........|\.........                     .........\.........                      .........\.........                       ..........#........                        .........#.........                         ........#..........
 * The ### is you, the dots are (stationary) raindrops, and the dotless areas on either side are shelters. You want to sweep the # figure in any upward/sideways direction, minimizing the number of dots you intersect. If you "stand still", you're moving up and to the left and intersecting more and more drops without bound, so that's bad. If you want to reach the shelter on the left, it appears that the most efficient way of doing it is to go directly to the left, which corresponds to running as fast as possible. If you want the reach the shelter on the right, the most efficient way appears to be straight up: since you're 1/3 as wide as you are tall, you intersect about 1/3 as many raindrops that way than if you went horizontally. This corresponds to running at the horizontal speed of the rain. But if the rain were falling more vertically, the shelter edges in this picture would be closer to vertical and going straight up wouldn't look so attractive any more. Once the slope of the sides exceeds 3, you're better off running as fast as possible. This approach still works if you add a third dimension and replace the rectangle with a more accurate human shape. -- BenRG (talk) 21:28, 4 August 2012 (UTC)

I asked a slightly more complicated version of this question here at the math desk: How wet will the windshield get? μηδείς (talk) 18:59, 4 August 2012 (UTC)


 * It is also important not to underthink the question. A tall skinny person moving at a certain speed with his body inclined at a certain angle will only get the top of his head wet, while at a faster speed he will run into the rain in front of him.  The cross section, angle of attack, and relevant speeds all matter.  See the link above for the definition of the variables in the formula ρ·s·A·(u·sin(Θ)/v+cos(Θ)) μηδείς (talk) 19:32, 4 August 2012 (UTC)


 * Time to bring in the Ultimate Authority: Mythbusters. They tested it and found you get wetter by running (at least for the way they set it up). Clarityfiend (talk) 00:34, 5 August 2012 (UTC)
 * They seem to have done only one trial per configuration, and there are no error bars.
 * The theoretical model predicts that when the rain is vertical the amount you absorb should be very similar whether you walk or run, but when walking a much larger fraction of it falls on your head. Their coveralls had no hoods.
 * Running might splash more water from the ground onto your legs.
 * They seemed to have no theoretical understanding of the thing they were studying, and they made no attempt to isolate possible causes of their surprising result. Yet they pronounced the myth busted. Very poor science. -- BenRG (talk) 02:07, 5 August 2012 (UTC)
 * Your graphic does seem to be an excellent proof of the fact that standing still in diagonally falling rain will get you infinitely wet. Does anyone have an opinion as to the validity of the formula I reposted? μηδείς (talk) 03:12, 5 August 2012 (UTC)
 * It looks correct to me. It's not the same problem, though. For an arbitrary rain direction I think it would be $$\rho (s/v) \vec A \cdot (\vec u + v \hat x)$$ where $$\vec A$$ is the directed area (unit normal times area). For an arbitrary shape (like a human figure) you'd need to replace $$\vec A$$ with a function that returned the cross-sectional area. -- BenRG (talk) 04:40, 5 August 2012 (UTC)
 * Having seen parts of episodes of Mythbusters before, I'm not exactly surprised. I'm sure they've done some okay stuff, but whenever I've seen they often seem to be pronouncing some myth busted or confirmed on the flimisiest of evidence. The lack of repetion or real theoretical understanding of what they're doing seems to be a common problem. This shouldn't exactly be surprising, it's a TV show and a lot of the nitty-gritty of real science isn't exactly exciting. It does seem to me people give way to much credence to them, particularly in complicated cases where things could easily have gone wrong. Nil Einne (talk) 05:34, 5 August 2012 (UTC))
 * That's disappointing even for Mythbusters. They specifically said in their intro that walking gets you head wetter and running gets your front wetter and then they only measured the water on their front. Of course they concluded the running gets you wetter... The show is obviously intended to be entertaining rather than rigorous, but it is usually a little better than that. --Tango (talk) 11:25, 5 August 2012 (UTC)
 * Well at least they didn't just fake the results when the actual results weren't cool enough I guess Nil Einne (talk) 19:05, 5 August 2012 (UTC)
 * If we're using Brainiac as our point of reference, then Mythbusters deservers a Nobel Prize! That show was ridiculous. --Tango (talk) 23:51, 5 August 2012 (UTC)
 * Count Iblis' approach only works if you're running at least as fast as the downward velocity of the raindrops (or even faster?) (i.e. never). When running slower, the raindrops you sweep out will be replaced by additional raindrops falling on you before you get out from underneath them.
 * Another consideration is how much more you will sweat when running than when walking and whether you would rather be drenched in sweat than in rain.--Wikimedes (talk) 06:50, 6 August 2012 (UTC)

Sweating only takes place if you are hot an the raindrops would nicely coole you. in addition running decreases the great differense between your speed and that of the raindrops meneing that the amount of water displaced while running is very slitely graiter then the amount of water that replaces it, if you are walking the amount of displaced water will still be very slitely greater then the amount of water that replaces it but less so. And don't forget that while the cerfase area of that portion of your body that gets wetter if you run (your front) is much greater then that of the portion of your body that gets wetter if you walk (the top of your head) remember that running gets you home much faster then walking.Aliafroz1901 (talk) 12:06, 8 August 2012 (UTC)

How many strings make up a quark?
I don't know if this question has a meaningful answer, but I'll throw it out there anyway. ScienceApe (talk) 16:21, 4 August 2012 (UTC)


 * String theory was originally a theory of strongly interacting quarks, in which a quark was the end of a string (thus explaining why single quarks never appear in isolation).


 * In superstring theory as a theory of quantum gravity, I think a quark would be "one string". Quarks are complicated even in the standard model, though, so take this with a grain of salt. -- BenRG (talk) 16:30, 4 August 2012 (UTC)