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March 19

Insanity...

Is the capability to display behavior patterns indicative of insanity in any way proof that the insane entity had a mind of its own to lose in the first place?

Just musing to myself about those neglected, stir-crazy, obsessive-compulsive, self-mutilating parrots at this late hour... --Kurt Shaped Box (talk) 02:42, 19 March 2008 (UTC)[reply]

While it certainly is possible for any creature with a brain to suffer a brain malfunction, I'd expect that complex minds are more likely to have complex malfunctions. So, strange obsessive-compulsive behavior may indeed be a sign of a fairly complex mind. A simpler mind would likely suffer from a more basic malfunction, like walking in circles instead of straight. I suggest you get the parrot in question a companion (or at least a cuttlebone to cuddle with). :-) StuRat (talk) 05:45, 19 March 2008 (UTC)[reply]

Biology: What are these caterpillars doing?

What are the caterpillars doing in this video? - Pureblade | ^Θ 04:46, 19 March 2008 (UTC)[reply]

I would speculate that they are exhibiting a defensive behaviour by co-ordinated action to give the impression of a larger creature. They may also be releasing body hairs containing a very powerful irritant. It is entirely possible that they sense the presence of the video operator and are reacting appropriately. I have experienced a similar effect with pine processional moths in Spain, when I blew on them gently they all jerked simultaneously. This seems to me to be an analogous behaviour. What is slightly odd, if these are pine processional moths, is that they are out feeding in the daylight. Of course they could be a related species demonstrating similar behaviour. Richard Avery (talk) 08:32, 19 March 2008 (UTC)[reply]

To me it looks like a sped-up version of the Macarena. Clearly somebody should tell these little buggers that it isn't cool anymore, if it every was. --Captain Ref Desk (talk) 19:49, 20 March 2008 (UTC)[reply]

But more honestly: I think they are Sawfly larvae. As to how they know to do this, this article is rather evocative. --Captain Ref Desk (talk) 19:49, 20 March 2008 (UTC)[reply]

Science in my gloves

We have to wear latex gloves in the cleanroom that I work in. Under these gloves we can wear a nylon glove liner. It's just a loose fitting liner so the glove isn't directly on your skin. I've noticed that sometimes as the night goes on, stains will develop inside my glove on the liner. The stains are blue like a bit of ink has found its way into the glove but the liners are white and stitched with white thread. There isn't any obvious source for the blue color. Some of the liners can be yellowed, almost as if they have been sitting in the sun, so I tried one of those to see if maybe the blue was due to a reaction between my sweat and whatever was yellowing the liners. I've only tested this once so far but the yellowed liner produced the blue stains while a whiter liner on my other hand did not. So what could be producing the blue color? Dismas|^(talk) 08:16, 19 March 2008 (UTC)[reply]

an off-the-wall guess.... povidone/iodine (from gloves or handwashing) + starch --> blue stain. - Nunh-huh 08:53, 19 March 2008 (UTC)[reply]

I guess I should have mentioned this but we are required to wash our hands using this white foamy soap before putting the gloves on. Dismas|^(talk) 09:01, 19 March 2008 (UTC)[reply]

Hi. This may be unrelated to your question, but usually in winter sometimes I wear normal gloves on the inside and waterproof ones on the outside. If the outside of my gloves get wet, sometimes the inside will too, and I often find disgusting colour marks on my hands afterwards. Talk about a green thumb, eh? Hope this helps. Thanks. ~A H 1^(TCU) 21:20, 19 March 2008 (UTC)[reply]

Two questions

What proportion of the scientific community believes the earth to be less than 100,000 years old and approximatly how accurate is carbon dating?--193.120.116.177 (talk) 11:02, 19 March 2008 (UTC)[reply]

And how old does the pope beleive the earth to be?--193.120.116.177 (talk) 11:18, 19 March 2008 (UTC)[reply]

Age of the Earth might help.

Zain Ebrahim (talk) 11:25, 19 March 2008 (UTC)[reply]

The Roman Catholic church does not have any theological issues with the earth being 4-6 billion years old. See Evolution and the Roman Catholic Church for related information. Specifically note what Cardinal Ratzinger (now Pope Benedict) said in a report: "According to the widely accepted scientific account, the universe erupted 15 billion years ago in an explosion called the 'Big Bang' and has been expanding and cooling ever since. Later there gradually emerged the conditions necessary for the formation of atoms, still later the condensation of galaxies and stars, and about 10 billion years later the formation of planets. In our own solar system and on earth (formed about 4.5 billion years ago), the conditions have been favorable to the emergence of life." -- 14:38, 19 March 2008 (UTC) —Preceding unsigned comment added by 128.104.112.85 (talk)

Do you have a reference for this?Zain Ebrahim (talk) 14:43, 19 March 2008 (UTC)[reply]

Found one: [1]. Zain Ebrahim (talk) 14:47, 19 March 2008 (UTC)[reply]

Carbon_dating#Calibration regarding the accuracy of carbon dating and radiometric_dating#Limitation_of_techniques for accuracy in dating the age of the earth. Lanfear's Bane | t 11:37, 19 March 2008 (UTC)[reply]

Carbon dating is just one kind of radiometric dating. It isn't used for determining the age of the Earth—it is only useful for dating things in smaller time periods than that. Uranium-lead dating is more common for things as old as the Earth.

As for how much of the scientific community believing the earth is less than 100,000 years old, practically none—a tiny number, insignificant when compared to the number of all scientists, and of those small number I imagine even smaller of them are active participants in a field of scientific inquiry that actually informs such assessments, or in what are considered to be real scientific institutions (not the Institute of Creation Research, for example).

There are quite a number of people outside the scientific community who believe that, but there is simply no compelling scientific evidence that the Earth is so "young" and much compelling evidence against the idea. I don't think it's an overstatement to say that the only people who believe the Earth is less than 100,000 years old are people who have a predisposition towards wanting to believe that on account of their religious beliefs.

As for the Pope, I am not aware of the current Pope's point of view vis a vis the age of the Earth. However perhaps you are referencing the work of the long-since-deceased Archbishop Ussher, who calculated that the Earth was only around 2,000 years old. --Captain Ref Desk (talk) 19:32, 19 March 2008 (UTC)[reply]

To be slightly more accurate than 'insignificant', Institute for Creation Research claims around 500 scientists (by which I think they mean those with a PhD in a scientific subject) that subscribe to their views. I'm not sure how many scientists there are in the US, but my guess is that this is substantially less than 1%. Interestingly it probably means that only a tiny fraction of scientists who are also Christians believe that the earth is less than 100,000 years old. DJ Clayworth (talk) 17:46, 19 March 2008 (UTC)[reply]

And it's the sort of number that gets smaller when you take their list and weed out all of those who 1. have degrees from non-accredited universities, and 2. are actively publishing or doing research in subjects related to things like the age of the Earth. I'm betting you'd cut the number down by quite a lot if you just took out the number of engineers—no offense made to engineers, but they seem to always predominate in the "people who think they really understand science deeply but actually have a fairly superficial working knowledge, and as such often overestimate their own competency in subjects they have not really studied seriously" category. --Captain Ref Desk (talk) 19:32, 19 March 2008 (UTC)[reply]

The precise stand of the Vatican on the Big Bang, Creation vs. Evolution, etc., can be found here: [[2]], at the Holy See's website; scroll down to paragraph 62. Other Christian denominations are not nearly so centralized, but in general the Anglican Communion has distanced itself from the notion of a 10,000 year old earth. In fact, in the West, the remaining "literalists" are largely Protestant denominations, many of whom have no fantastic claim to antiquity themselves. Vance.mcpherson (talk) 20:38, 19 March 2008 (UTC)[reply]

How do you poison a dress?

(I'm not sure whether I should post this at the Humanities-desk or here, but I figure since it has to do with medicine than history, Science would be most appropriate)

I saw the movie Elizabeth (the one with Cate Blanchett) a while ago, and something struck me: there is a subplot in it about an attempted assassination of Elizabeth using a dress that had been poisoned, so that when she would put it on, she would die (the attempt failed, obviously). That seems to me to be a not uncommon motif in literature, poisoning a dress. The most obvious other example is Medea killing Creon and Glauce by poisoning a dress.

Is this possible? I mean, can you make a dress that otherwise looks (and smells) normal, but when you touch it or wear it, it will poison you? Supposing you could, could you do it in the 16th century? I mean, if you just dunk it in a vat of arsenic-contaminated water (or something), wouldn't it be all discolored and also smell pretty foul? And is this just part of mythology, or has there ever been an attempt of using this method of assassination? --Oskar 14:45, 19 March 2008 (UTC)[reply]

It would be possible, but it seems to be firmly in the territory of soap opera and mythology. - Nunh-huh 15:43, 19 March 2008 (UTC)[reply]

So say you were a 16th century cardinal who didn't like all this Church of England nonsense, how would you do it? --Oskar 17:38, 19 March 2008 (UTC)[reply]

Get out of town? - Nunh-huh 17:49, 19 March 2008 (UTC)[reply]

Maybe it was soaked in cyanide with a nice almond scent. -- MacAddct  1984 ^{(talk  contribs)} 16:14, 19 March 2008 (UTC)[reply]

Well, the CIA considered giving Fidel Castro a poisoned wet suit, so why not? --Sean 17:11, 19 March 2008 (UTC)[reply]

Coupla drops of dimethyl mercury would do it (but long-drawn-out, not quick-convulse&die), but not sure anyone in the 1500s would be able to handle that stuff. Heck, even today it is hard to handle safely. DMacks (talk) 19:14, 19 March 2008 (UTC)[reply]

Pyrrole might be a good candidate, as it is a permeator. See [[3]]. Have no idea how they'd get the stuff in Elizabethan times, though, the synthesis of it is complex ([[4]]).Vance.mcpherson (talk) 20:50, 19 March 2008 (UTC)[reply]

Lots of things permeate skin, but need something that is reliably toxic in a dose small enough to be delivered that way. The MSDS you cite lists an acute LD₅₀ of 98 mg/kg (mouse, orally), so even if that's the right ballpark for (human, dermal), we're talking several dozen mL to absorb. In smaller doses, it's not that toxic (see note on pyrrole about its use in cigarettes). DMacks (talk) 21:00, 19 March 2008 (UTC)[reply]

I like the idea of having small poison-tipped spikes somewhere inside the dress. Mac Davis (talk) 01:47, 20 March 2008 (UTC)[reply]

How about soaking the dress in nicotine ? It's absorbed through the skin and can cause death if enough is absorbed transdermally. Tobacco farmers must wear gloves when harvesting tobacco leaves, especially after a dew or rain, as concentrated nicotine in the rain drops will pass through the skin on the hands and can cause death. StuRat (talk) 04:17, 20 March 2008 (UTC)[reply]

Of course it works. Just ask Hercules. sho y 16:42, 20 March 2008 (UTC)[reply]

I think the trick is social engineering. Even if the soaking is visible and can be smelt, you could convince the target that it's a "refreshing" or "wellness" shirt or something. – b_jonas 17:21, 20 March 2008 (UTC)[reply]

Here's how I would do it. Get some venom from a Golden Poison Frog. The batrachotoxin from the frog is so lethal that only 100 micrograms (equivalent to 2 grains of ordinary table salt) will kill a 150-pound person. Skin contact with this stuff may be sufficient, but I would mix it with dimethyl sulfoxide (available from drug stores or nutrition stores), a chemical that can be used to carry other substances through the skin. Apply drops of this to parts of the dress that would be touching the skin, shortly before the dress is worn. The wearer may taste garlic just prior to dropping dead. ~Amatulić (talk) 17:40, 25 March 2008 (UTC)[reply]

hey

wats is the common and scientific name for sponges,flat worms, earthworms, bugs, frogs, jellyfish, round worms, clams, and starfish —Preceding unsigned comment added by 165.29.165.253 (talk) 15:14, 19 March 2008 (UTC)[reply]

Well, you just listed their common names. Scientific names will depend of each species of the animal you want; out of those groups there are probably millions(?) of different species. The only group they all fall under is the kingdom "Animalia". -- MacAddct  1984 ^{(talk  contribs)} 15:27, 19 March 2008 (UTC)[reply]

Simple enough eg type 'sponge' into the search box gives the sponge page which tells that they are all of the phylum 'Porifera'. You can do the same for the rest. type 'insects' for 'bugs'.83.100.183.180 (talk) 15:50, 19 March 2008 (UTC)[reply]

Well the whole collection together could be animals! or cold blooded animals Graeme Bartlett (talk) 05:13, 20 March 2008 (UTC)[reply]

Invertebrates? Sandman30s (talk) 07:55, 20 March 2008 (UTC)[reply]

...apart from the frog, of course. Gandalf61 (talk) 10:50, 20 March 2008 (UTC)[reply]

And invertebrates is a fairly silly name based on exclusion rather than inclusion, i.e., defined as animals without a backbone. Proper nomenclature is never based on exclusion it's just a vertebrate (human) bias. --jjron (talk) 14:10, 21 March 2008 (UTC)[reply]

Tantalum hafnium carbide

We don't have any reference in the article Tantalum hafnium carbide, the substance with the highest melting point known (?). Where is the publication on the 4488 K melting point? Thanks in advance. Icek (talk) 15:55, 19 March 2008 (UTC)[reply]

This Britannica article is a very reliable source. --Bowlhover (talk) 16:00, 19 March 2008 (UTC)[reply]

Thank you, but does anyone know where to find the original publication? Icek (talk) 16:12, 19 March 2008 (UTC)[reply]

Google told me that the phrase "The alloy tantalum hafnium carbide. (Ta. 4. HfC. 5. ), with a melting point of 42158C,. is one of the most refractory substances" appears in "11 Hafnium" of doi:10.1002/9783527619634.ch32, but I don't have access to the actual text from here. A publication like that is probably well-footnoted to primary and/or reputable secondary sources. DMacks (talk) 19:12, 19 March 2008 (UTC)[reply]

New car smell

I just found out today that the new car smell is toxic and carcinogenic. So what should we do to avoid it? Would opening the windows help? --Lazar Taxon (talk) 17:26, 19 March 2008 (UTC)[reply]

Do you have a reference for this? It would surprise me (at least, in the US, with all our emphasis on car safety) that manufacturers would sell a toxic product. But, assuming you do want to avoid it.. the easiest way would seem to be, don't get a new car. Letting it air out sure seems like it wouldn't hurt either. Friday (talk) 17:36, 19 March 2008 (UTC)[reply]

I think it's more about the regulatory bodies not allowing a product to be sold that's clearly and undeniably toxic. If a company can plausibly deny a product's harmfulness (see Crisco, Dupont), that's good enough for the feds. Vranak (talk) 20:04, 19 March 2008 (UTC)[reply]

Found a couple sources: From a few years ago, saying it might be toxic, and more recently saying it's not toxic. This is what I get for not checking the wiki first- we have a decent article on this at New car smell. Friday (talk) 17:40, 19 March 2008 (UTC)[reply]

This sounds similar to the more serious problem of "new house smell". Carpets, paint, furniture, etc., all outgas fumes, some of which are toxic if they build up beyond a given concentration. This is more of a problem in recent constructions because they are designed to be more airtight. You'd think they would start to offer a service to air rugs and furniture out before they are installed, so as to allow the toxic fumes to exit. StuRat (talk) 04:10, 20 March 2008 (UTC)[reply]

New Solar Chip

I found an interesting article and forgot to bookmark it. Now I cannot find it again.

I was looking at a new type of photovoltaic device that converts sunlight directly to electricity using a photochemical nano-gate composed of niobium [columbium], gold and silver, interchangeably, on one side of the gate. There was a separate and different word to describe this type of PV cell in its own page, and I cannot remember the word.

I have tried every combination of "solar power energy photovoltaic [columbium niobium] gold silver" that I can think of in your search engine, and in Google's search engine with wiki as the first word, and I can not find the article again.

Please help me find that page again.

The above was posted to the Help Desk recently and responses have not been helpful. Does anyone have any info on the above described chip, now undergoing testing, that was described on a Wikipedia page? External links welcomed.

was it a gratzel cell? 131.111.100.44 (talk) 18:05, 19 March 2008 (UTC)[reply]

Gravity

I was just reading an article on howstuffworks.com and i though came to me, if all the gravity on earth magically disappeared, would everything float up, surely it would just stay put, coz there wouldn't be a force acting on it?Vagery (talk) 19:20, 19 March 2008 (UTC)[reply]

Not exactly. Objects would slowly move away from the Earth and slightly east as the Earth rotated away from them. Drawing a picture of the rotating Earth and the object on it may help. It isn't that the object accelerates up, it's that the Earth underneath accelerates away from the object. anonymous6494 19:27, 19 March 2008 (UTC)[reply]

Thats what i thought would happen... just checking, thnx alot manVagery (talk) 19:29, 19 March 2008 (UTC)[reply]

Um, a person at the equator is traveling with the Earth's rotation, at a rate of 40,000km (earth's circumference) per 24 hours (length of one rotation), or, if my quick math is right, about 360m/s. Initially, said person will appear to stay put, but will in reality start moving 360m/s in a straight line, as will the ground under his feet. It wouldn't take long for things to start spreading out at that speed. Naturally, the velocity will be lower for people not on the equator, but you can do the math for that yourself, multiplying that velocity by a trig function that gives you 1 for the equator and 0 for the poles. -SandyJax (talk) 19:58, 19 March 2008 (UTC)[reply]

Would the entire Earth fly apart? The plates of the crust aren't firmly stuck together, so there'd be nothing holding them down, right? And then the layers underneath are mostly solid only because of pressure, so once the layers above are gone, they'd become fluid again and spin off? Or would they cool down fast enough to remain solid? --Allen (talk) 20:38, 19 March 2008 (UTC)[reply]

If gravity disappeared only in a sphere equal to the size of Earth, then everything within that sphere would move in the same direction relative to the distant stars that it was moving at the instant that gravity disappeared, so yes, it would all fly apart pretty quickly. There would be no more reason to rotate and everything would move in straight (geodesic) lines instead. Electromagnetic forces would still keep stuff stuck together, i.e. rocks would still be rocks and magma would quickly solidify into rocks, all those rocks would continue in a straight line. That's how I see it anyway. Franamax (talk) 21:14, 19 March 2008 (UTC)[reply]

Clarify this, I didn't mean "instead" - everything is already moving along the geodesic, it just so happens that the Earth's mass shapes the local space-time continuum so that the "shortest path" is to spin around in a circle (the shortest path is actually to the centre, but that pesky ground keeps us from getting there). Removing gravity from the sphere around Earth means that the geodesic path is now determined by all the rest of the gravity in the universe, space-time is no longer warped right here, all the marbles will roll down other slopes. That's probably not clarifying anything! Franamax (talk) 22:19, 19 March 2008 (UTC)[reply]

Battleships in space

Years ago I read somewhere that steel retrieved from pre-1945 battleships was an essential component of satellites. The reason given was that all the steel smelted since 1945 (or shortly thereafter) was contaminated with radioactive elements from nuclear explosions to sufficient degree that it would affect the satellite instrumentation.

I'm not sure whether this was only for the Pioneer/Voyager probes and I'm not sure whether it was just one particular battleship, but I know I read it once and I've never been able to find a reference since. Can anyone help me out? Franamax (talk) 20:58, 19 March 2008 (UTC)[reply]

Operation Deadlight 83.100.183.180 (talk) 21:15, 19 March 2008 (UTC)[reply]

Wow, that was fast! Thank you Wikipedia, and thank you all the anonymous editors who help to build it, especially you 83.100. I believe it was the scuttled ships at Scapa Flow that I had read about. Next question: what radiation detectors is this steel used in? All of them? Where can I read up on this some more? And does anyone have a specific reference to satellites? I'm trying to build a killer trivia question here, or maybe even a Wikipedia article. Thanks. Franamax (talk) 21:38, 19 March 2008 (UTC)[reply]

Very old lead is also used. —Preceding unsigned comment added by 58.84.80.184 (talk) 21:59, 19 March 2008 (UTC)[reply]

I had heard that metal from ship wrecks was being used as casing for supercomputers because all metal was slightly radioactive just due to normal cosmic radiation that was only blocked by the deep seas, especially since some of the elements involved have half-lives of several decades. I think it's needed in supercomputers because they have trillions of bits of memory that make the slim chance that a high-speed particle will inadvertently flip one. Satellites have no protection from the atmosphere, so probably all of their delicate instruments/computer parts need this sort of protection. Quantumelfmage (talk) 20:21, 23 March 2008 (UTC)[reply]

Wow, sorry to hijack the question, but am I understanding this correctly? All steel produced since Hiroshima/Nagasaki is tainted with radioactive elements? The Operation Deadlight article isn't very clear, and I'm having a hard time believing it's true. What mechanism causes iron mined on, say, the other side of Japan to become contaminated? Thanks, Icthyos (talk) 11:03, 20 March 2008 (UTC)[reply]

I would guess (but have not been able to verify) that it is the oxygen blown through during the conversion process (see Linz-Donawitz process and Bessemer process) that has atmospheric contamination, not the ore. -- Q Chris (talk) 12:41, 20 March 2008 (UTC)[reply]

Yes, it is the air used smelting the iron and oxygen used in making the steel that introduces atmospheric contamination. Old steel can be hot-reworked so that no new air is incorporated. Incidentally, people born since 1945 can have their age determined (plus-minus a few years) by the radioactivity of their teeth. Franamax (talk) 17:12, 20 March 2008 (UTC)[reply]

It isn't just Hiroshima and Nagasaki—it's the other ~600 or so atmospheric tests as well that took place from 1946-1980 by various nations in the world. It'd be interesting to total up the cumulative megatonnage from the years of atmospheric testing, but it is well over 100MT. It would be wonderful if someone had data for background radiation levels over the 20th century, I'm sure it would be an interesting graph. --Captain Ref Desk (talk) 19:33, 20 March 2008 (UTC)[reply]

Nature Vol.437 p.433 15Sep05 Age written in teeth by nuclear tests Spalding et al has an interesting graph of atmospheric carbon-14 levels. I have a Nature subscription, see if you have access to the article here. There is some info on copyright licensing here which I don't understand, but I doubt it would be released under GFDL. The C14 ratio is stable until 1955 (when above-ground testing really got going), rises quickly to +20% by 1960, dipsy-doodles 'til '62, then skyrockets to +85% by 1965, exponential decay thereafter. We're down to approx. +8% now. Other radiation levels would likely look similar as it is diffusion out of the atmosphere that predominates over radioactive decay. Of course, a lot of the radioactive elements would still be in organic materials, water, teeth, etc. Franamax (talk) 20:00, 20 March 2008 (UTC)[reply]

PS There are little notches at 1972 and 1980 where further tests had been conducted. Franamax (talk) 20:04, 20 March 2008 (UTC)[reply]

That's not bad. Not quite as ideal as having the direct background radiation data, but still not bad. I looked at the supplementary data to see where their data source for the background C¹⁴ levels were from and found a few useful references... will see if there's data I can make a new graph out of. Supposedly all the data from that issue should be at this site but the site is current down. :-( --Captain Ref Desk (talk) 01:19, 21 March 2008 (UTC)[reply]

Actually, now that I look at it, I've seen these graphs before. We have one not too dissimilar even though it's only from the Southern Hemisphere. The data sets above are much more complete (judging from the articles in Radiocarbon) so maybe we can make a more exciting one in the near future. --Captain Ref Desk (talk) 01:24, 21 March 2008 (UTC)[reply]

Nice find on the Commons image! According to Greenpeace, 711 atmos or water tests, 438 Mt total atmos test yield, 4200 kg Pu atmospheric discharge(!!) - Greenpeace of course being a neutral source :) (though there's no reason to think they wouldn't be reliable on this).

I couldn't get at the Radiocarbon journal data, unless Jimbo wants to buy us those issues. I agree that total release of radionuclides and overall radio-persistence would be interesting. Now include decay products, organic persistence, half-lives - add in contaminated steel, dating of teeth, and one more persistent effect we could identify - we've got ourselves a new Wikipedia article: Persistent effects of atmospheric nuclear detonations. What's your diagnosis Doctor Strangelove? Franamax (talk) 02:01, 21 March 2008 (UTC)[reply]

Wiki Myth Busters...

So when you pull the ol' snap your friend in the butt with a towel prank, the snapping noise is caused by the end of the towel breaking the sound barrier. True or false? Beekone (talk) 21:09, 19 March 2008 (UTC)[reply]

Why wouldn't the snapping noise just come from part of the towel moving quickly? Mac Davis (talk) 21:50, 19 March 2008 (UTC)[reply]

According to Whipcracking, at least some whips create a cracking noise by breaking the sound barrier. Whether the towel works that way I don't know; it seems a lot shorter than most of the whips shown as being crackable in the article. --Allen (talk) 21:57, 19 March 2008 (UTC)[reply]

Straight Dope talks about it: http://www.straightdope.com/mailbag/mtowelsnap.html DMacks (talk) 22:05, 19 March 2008 (UTC)[reply]

Seems highly unlikely to me. You can 'snap' a towel (wet or dry) pretty slowly and still get a pleasing noise. The towel changing direction is large enough to compress a sufficient amount of air to create a fairly flat noise. And any ol' Joe can do it pretty much first time every time. The tip, or any other part of the towel, doesn't have to moving anywhere near the speed of sound for this to occur. This is different to cracking a whip where a long whip allows a small tip to achieve a very high speed, greater than the speed of sound, resulting in the loud crack, and it's rather more difficult for people to do without some practice. Move a whip slowly and it won't crack at all. Personally I'd say 'Busted', or at least 'Implausible'. --jjron (talk) 14:03, 21 March 2008 (UTC)[reply]

according to this site http://www.sciam.com/article.cfm?id=true-cause-of-whips-crack even classic whip crack is not caused by breaking sound barrier. Even though the speed of sound is surpassed --Urwald (talk) 18:22, 11 May 2008 (UTC)[reply]

medical terminology, not sure of spelling or existence

I was told to go to "fae" under frequent asked question. I'm trying to find out about physcadose. Possibly something to do with the liver. Is there such a word? I'm not sure of the spelling, can you help me?71.91.46.235 (talk) 22:20, 19 March 2008 (UTC)[reply]

Definitely not a word as you've written it, and no similar sounding word pops to mind. Where did you hear this word? - Nunh-huh 23:37, 19 March 2008 (UTC)[reply]

It's a bit of a stretch, but sarcoidosis? -- MacAddct  1984 ^{(talk  contribs)} 01:43, 20 March 2008 (UTC)[reply]

Turtle identification

I recently took photos (here is one of them) of a turtle on our pond that seems to be a Chicken Turtle (thanks to Joelr31 for pointing me in the right direction). I wanted to use a cropped version of the previously linked image in the chicken turtle article, but first I'd like to confirm the identification here. After looking at a bunch of pictures on the web, I'm not perfectly sure it is, in fact, a chicken turtle. As for geographic info, I live in upstate South Carolina, USA. I don't really have ideas of what else it could be, but some of the coloration/shell ridges of this turtle don't quite seem like the species, although there's probably room for variation. Are there any other species it could possibly be, or is it pretty obvious that it's a chicken turtle? Just wanted to make sure of this to hopefully prevent some misinformation here on Wikipedia. :) --JamieS93 23:41, 19 March 2008 (UTC)[reply]

Well, it could easily be the more common Painted Turtle, or something else entirely. The red coloration doesn't appear to be standard for a Chicken Turtle, and while his/her neck is long, it isn't as long as some pictures identified as chicken turtles. Personally I'd be hesitant, but I don't know a thing about turtles.--Captain Ref Desk (talk) 20:15, 21 March 2008 (UTC)[reply]