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December 5

Has the mass of our sun or things in our solar system ever been measured with gravitational lensing?

Has the mass of our sun ever been measured with gravitational lensing? Normally mass is measured http://imagine.gsfc.nasa.gov/YBA/cyg-X1-mass/mass-of-sun.html http://en.wikipedia.org/wiki/Mass_of_Sun in this sort of pre-Einstein way. I cannot find any source where it's been measured with gravitational lensing. Same for planets in our solar system (I don't mean planets in other solar systems). So anyone know of our sun, planets, or moons in our solar system being measured by gravitatonal lensing? It would be interesting to compare the gravitational lensing vs. pre-einstein-type measurements and see if they match. Are you ready for IPv6? (talk) 00:56, 5 December 2011 (UTC)

Well, Eddington's observational confirmation of relativity during the Solar eclipse of May 29, 1919 showed the lensing effect was as predicted given the estimated mass of the Sun. -- Finlay McWalterჷTalk 01:06, 5 December 2011 (UTC)

Rate equations

Have I derived the following 6 differential equations correctly? This isn't something I've done before and I want to be absolutely sure I'm correct. 184.98.169.135 (talk) 02:17, 5 December 2011 (UTC)

1. A <-> B

   dA / dt = k_r [B] - k_f[A]

   dB / dt = k_f [A] - k_r[B]

2. A -> B + C

   dA / dt = -k_f [A]

   dB / dt = k_f [A] / 2

   dC / dt = k_f [A] / 2

3. A -> B

   dA / dt = -k_f[A]

   dB / dt = k_f [A]

4. A -> A + B

   dA / dt = 0

   dB / dt = k_f [A]

5. A + A <-> B

   dA / dt = k_r [B] / 2 - k_f [A]^2

   dB / dt = k_f [A]^2 - k_r [B] / 2

6. A + B <-> C

   dA / dt = k_r[C] / 2 - k_f[A][B] / 2

   dC / dt = k_f[A][B] - k_r[C]

   dB / dt = k_r[C] / 2 - k_f[A][B] / 2

You're close, but you'll want to check your equations for the second, fifth, and sixth reactions. For example, for reaction #2, each mole of A consumed results in a mole of B and a mole of C formed, therefore dB/dt = dC/dt = -dA/dt. The way that you've written your differential equations assumes that for each mole of A consumed, half a mole each of B and C are formed. TenOfAllTrades(talk) 02:39, 5 December 2011 (UTC)

Wind energy and health

Hi. Recently in Ontario there have been many protests and also legal action against the installment of wind turbines (to verify, do a Google News search). Many rural families claim that the turbines cause effects such as vertigo, dizziness, insomnia, headaches, myalgia, and other complications. Yet why are these cases seemingly limited to Canada, and are there any similar complaints from other countries, and are they covered in Wikipedia? Thanks. ~AH1 ^(discuss!) 02:57, 5 December 2011 (UTC)

You might find your questions answered in one or more of these documents.

• ACOUSTIC ECOLOGY | Special Report: Wind Energy Noise Impacts
• Wind Turbine Syndrome: A Report on a Natural Experiment
• Responses of the ear to low frequency sounds, infrasound and wind turbines
• The Ear, Infrasound and Wind Turbines

See also the article "Environmental impact of wind power”.

—Wavelength (talk) 03:12, 5 December 2011 (UTC)

Ohio's highest point is located in the county where I grew up. A few years ago they tried to put in turbines, but protestors made similarly absurd claims — and even more unrealistic ideas as well, such as the idea that turbines cause seizures and that they're so loud that they will cause deafness. It can't be that often that you find an issue on which hardline Greens oppose the renewable energy source...Nyttend (talk) 04:42, 5 December 2011 (UTC)

Like when those hypocritical eco-Luddites (such as Nina Pierpoint, who apparently wants to send the whole country back two hundred years) demonstrated against the Mojave Desert solar plant on the pretext that "the construction methods used to build the plant involve toxic materials" (even though they don't)? BTW, I'm not a fan of solar power (too many problems with it, both technical, economic and geopolitical), but those people's position on these issues clearly demonstrates that they're not so much interested in reducing pollution as they are in depriving the civilized world of all the benefits of modern technology. 67.169.177.176 (talk) 05:06, 5 December 2011 (UTC)

Presumably you mean Nina Pierpont. -- ToE 11:27, 5 December 2011 (UTC)

I did a very (very) quick search of Polish-language Internet (we have been having literally tens or even hundreds of new turbines installed in recent years and loads more are on the way), and I found local inhabitants' protests appealing to poorly written plans of wind farms, lack of wind, destruction of the landscape (this one was the topic of a protest somewhere in a mountainous region), or without citing a reason - it was just that the people plainly didn't want turbines close to their homes, full stop. No appeals concerning health or related issues (but this was a quick search though). Sorry for the brevity but I've got a project to hand in this morning. --Ouro (blah blah) 06:58, 5 December 2011 (UTC)

Editor 67.169.177.176, wind turbines have caused health problems to many people. Which is more important: technological benefits or human health?

—Wavelength (talk) 17:18, 6 December 2011 (UTC)

Editor Wavelength: No they haven't, except in anecdotal reports from technophobic nutjobs like Pierpont (who are most likely pursuing an agenda to return our country back to the stone age, considering their opposition to all other energy sources, whether dirty or clean). The vast majority of peer-reviewed reports indicate little or no impact on human health. Besides, what's worse, a few cases of insomnia in a small percentage of the population, or worse effects on human health from other energy sources (air pollution from conventional "dirty" coal plants, etc.), or maybe having to do without any kind of energy at all (which is what will happen if the green luddites have their way)? Are you really so dumb as to believe the crazy fanatics, or are you pursuing a political agenda? 67.169.177.176 (talk) 01:49, 7 December 2011 (UTC)

Here are a few points in reply.

• If you see my first post above and read the pages to which I have linked, you can learn about many people in many places with health problems. Also, there are links to additional pages with additional information.
• If you see this page and search for arousal, you can read what Dr Christopher Hanning has said.
• Many humans make inadequate use of human energy.
• Much energy is wasted on the overproduction and overconsumption of non-essential items.
• Many cities can promote energy conservation by improving walkability.
• Nina Pierpont and I do not need to be ahead of our time in recognizing the health hazards of wind turbines. I hope that you have an honest heart and an open mind.

—Wavelength (talk) 03:33, 7 December 2011 (UTC)

Aha, just like I thought -- another Luddite trying to end "overproduction and overconsumption of non-essential items" (i.e. any semblance of prosperity and modernity in everyone's way of life). Very well then, why don't you start practicing what you preach -- get rid of your computer, sell your car for scrap, start using "human energy" in all your household tasks (that means you do everything by hand -- no vacuum cleaners, no washing machines or clothes dryers, no dishwashers, no blenders, no nothing), and use torches instead of electricity for illumination, and let's see how long it will take until you start wishing for your "non-essential items" again. By the way, if your goal is to end humanity's dependence on electric power, how come you're even using a computer and the Internet in the first place, hypocrite?! 67.169.177.176 (talk) 07:48, 7 December 2011 (UTC)

And as far as the linked documents in your first post are concerned, they are all authored by Luddite nutjobs like Pierpont and you, and have zero credibility in the scientific community. 67.169.177.176 (talk) 07:53, 7 December 2011 (UTC)

Here are some comments in reply.

• According to wikt:hypocrite, a hypocrite is "[s]omeone who practices hypocrisy, who pretends to hold beliefs, or whose actions are not consistent with their claimed beliefs." I did not claim to be perfect. You and I are imperfect humans in an imperfect world (that is to say, in an imperfect societal arrangement). We do not need to take an all-or-nothing position in regards to doing good. Each person can do his or her best in an imperfect situation.
• You do not know my net environmental footprint. You do not know what environmental adjustments I have already made. You do not know how I travel or how much I travel. With a few exceptions, you do not know my abilities and you do not know my needs.
• If everyone else in my community wants to drive a motorcar, and if the infrastructure is designed for the motorcar, and if the local government has outlawed the use of horses and buggies on local thoroughfares, then who would expect me to travel by horse and buggy on local thoroughfares?
• One person can not necessarily make a big difference, but one person can still make decisions according to principles. A decision made according to right principles can make a difference for the better. If everyone makes decisions according to right principles, then collectively they can make a big difference for the better.
• Each person can invite and encourage others to make decisions according to right principles, but ultimately each person is an agent of free will. We can lead a horse to water, but we can not make it drink.

—Wavelength (talk) 19:37, 7 December 2011 (UTC)

Here are some comments in reply to YOU:

(1) Regardless of any adjustments you might have made, you have still shown yourself to be a hypocrite by using a technology that consumes electricity on a continuous basis (i.e. your computer), while at the same time opposing the production of electricity even from such clean and renewable sources as wind power. Need I say more?

(2) Is there ANYONE in his/her right mind who would choose to travel by horse and buggy in this day and age, even if the infrastructure and municipal laws allow for it? Traveling by motorcar is so much superior in every practical respect to travel by horse and buggy that only an incurable Luddite would choose the latter.

(3) What makes you think that principles which limit economic development (as evident from your comments about "overproduction and overconsumption of unnecessary items") are the right ones? It is PRECISELY the unrestricted exploitation of our energy resources (among other things) that made the USA into the most prosperous nation in the world, and any principles that would diminish our prosperity (such as those that call for limiting such exploitation, as you are doing) by definition CANNOT be right ones or make a difference for the better. (Not unless by "making a difference for the better" you mean "turning our country into a third-world nation and forcing everyone to travel by horse and buggy instead of by motorcar"!) 67.169.177.176 (talk) 07:29, 8 December 2011 (UTC)

Do you see the differences?

(1) There is a difference between "production and consumption" and "overproduction and overconsumption".

(2) There is a difference between the sound of a motorcar and the sound of a horse and buggy. See The Surrey with the Fringe on Top and OKLAHOMA "The Surrey With The Fringe On Top" with lyrics - YouTube.

(3) There is a difference between ecological extremism versus economic prosperity and economic extremism versus ecological prosperity.

—Wavelength (talk) 06:39, 9 December 2011 (UTC)

OK, watch me demolish your arguments one by one:

(1) First of all, "overproduction and overconsumption" is a purely arbitrary concept -- in reality, every economy strives (and SHOULD strive) to maximize production and expand its production possibilities frontier in order to maximize prosperity for each and every person who is part of that economy. The moment you start placing arbitrary limits on production, you limit economic prosperity for EVERYONE in the country and send the economy back on the way to collapse and destitution (as can be seen from the example of the USSR, where the government outlawed private enterprise and placed arbitrary limits on the accumulation of wealth).

(2) The sound of a motorcar vs. that of a horse and buggy is irrelevant to this discussion -- the practical advantages of a motorcar (speed, comfort, payload) are so overwhelming that to propose replacing it with a horse and buggy based merely on the difference in sound is completely preposterous!

(3) There's no such thing as "ecological prosperity" (unless you invented this concept) -- economic prosperity is what matters to any normal person (unless you prefer to live like a hermit in the woods), so unless you're ready to concede defeat you better at least define "ecological prosperity" AND PROVE that it should matter as much as, or more than, economic prosperity. 67.169.177.176 (talk) 06:58, 9 December 2011 (UTC)

Wind power seems like a bit of a NIMBY issue. That is, while most people like the idea in theory, they don't want huge wind turbines near them. Of course, many other power sources have a similar issue, as nobody wants a coal-fired plant, a nuclear plant, etc. next door, either. However, since wind farms must be spread over wider areas, they are likely to be in more people's "back yards". Solar collectors have the advantage of not being noisy and not having pieces that can fly off at high speeds, so they might be a bit more acceptable. StuRat (talk) 20:24, 5 December 2011 (UTC)

At the price of being much more expensive and less efficient. 67.169.177.176 (talk) 23:55, 5 December 2011 (UTC)

Solar does have the advantage of providing the most energy on sunny days, which, during summer, is when our electrical supply is the most overstretched by air conditioners and subject to brownouts or blackouts. So, while not suitable as a primary electrical supply, it makes a good supplemental source. StuRat (talk) 17:58, 6 December 2011 (UTC)

Perhaps -- but the high production costs still makes them uneconomical without government subsidies. 67.169.177.176 (talk) 01:51, 7 December 2011 (UTC)

Additional nuclear and coal-fired power plants to supply peak-energy needs also require subsidies, usually in the form of approval for higher rates to customers. StuRat (talk) 20:13, 9 December 2011 (UTC)

I should say that there is no doubt in my mind that wind turbines can ruin a neighborhood - for example, there is a formerly very pleasant state gameland near Aristes, Pennsylvania which included a secluded valley, isolated by hills from all roads, one of the few remaining spots in its entire region unspoiled by machine noise, except when planes (frequently) flew over. Now one of those hills is lined with the turbines and the feel of the area is just ruined. That's the sad end of the NIMBY-based decision making - the unspoiled places are singled out for destruction. The big disappointment with wind power for me is that there are vast, vast tracts of empty land blasted by the noise of adjacent major highways, but there is no effort at all to place these things in the area that is already ruined. Like the illegal dumpers who each somehow manage to find a way far from the beaten path so that they can dump their own waste somewhere never before defiled, the noisemakers of wind power apparently take no satisfaction from ruining what is already ruined. Wnt (talk) 20:48, 7 December 2011 (UTC)

See Wind Powering America: Siting Wind Turbines, with a link "Siting Considerations in New England", New England being near to Pennsylvania.

—Wavelength (talk) 21:49, 7 December 2011 (UTC)

Wind turbines are (and SHOULD BE) placed where the wind is strong and fairly constant -- any effort to prevent the best possible sites from being used for wind power production merely on the grounds of it being an "unspoiled place" is nothing more than blatant hypocrisy on the part of environmental activists. I mean just think of it, first they demand that renewable power be used for ALL of our country's energy needs (even though it would be completely impossible for renewables to meet 100% of our electricity consumption, or to be even remotely useful for transportation), but then when it comes time to actually BUILD the dam site (or the windmill, or the solar plant -- not necessarily hydropower), all of a sudden they come up with some moronic pretext (like "infrasound emissions" in this case) to OPPOSE renewable energy?! What hypocrites! 67.169.177.176 (talk) 07:41, 8 December 2011 (UTC)

Sound is also part of the environment. The myriad species of birds, insects, and mammals coordinate their calls, among the sounds of the trees and grasses and wind and rain, like the instruments of a symphony, each with its own frequencies and times and places of transmission to maintain a natural order. The universal and perversely deliberate destruction of this beauty wherever it can be found is not merely a tremendous oppression to the human ear and spirit, but also damaging to human cardiovascular health and intellectual development. And in the long run, I fear it will lead to the destruction of even the potential for nature to sing these songs. When insects and birds and mammals compete with cars and air conditioners and wind turbines to be heard, the old parameters of natural selection are set aside. Each player, without feedback, loses its well-rehearsed talent - and collectively, they will no longer be able to integrate with one another in the old ways. What is being destroyed is not merely the sound of nature here and now for you and I, but in its entirety. Wnt (talk) 03:59, 9 December 2011 (UTC)

And for that reason you want to deprive everyone of electricity, you Luddite? Well, I got news for you -- EVERY aspect of EVERY civilization (whether bronze smelting in ancient Greece, textile-making in Renaissance England, or electricity generation in America today, no matter how clean or renewable) WILL have an impact on nature, so unless you wanna have everyone go back to the stone age, you better get used to it and stop bitching about the "destruction of natural beauty"! It's the price to pay for not having to live in caves and hunt buffalo with flint spears, so get over it! 67.169.177.176 (talk) 06:37, 9 December 2011 (UTC)

But we pick and choose which impacts we accept and which we reject, according to our values. We do that the moment we have any regulation against any form of pollution whatsoever. Just because you don't want to live in a cave doesn't mean you want to have a heart attack or asthma from noise or pollution just so that some rich fellow can ride a lift up a hill and slide down the artificial snow under brilliant spotlights all night long. We make choices about what we value and defend. My values are such that I would accept a line of windmills in public land along a major highway, because the area ruined by noise is reduced, and excuse the toll on migratory birds and the degradation of the visual appearance to passing motorists for the benefit of decreasing imported fossil fuel use and carbon emissions. I hardly consider myself a fanatic - I am more than willing to accept cheap coal power provided that real and serious effort is taken toward reducing all of its environmental impacts, such as carbon sequestration and avoiding acid rain, and provided that the damage done by mining is strictly limited. But the song of the land has been so terribly oppressed, throughout the land and even in the depths of the sea, and those few places where it remains need meaningful respect. Wnt (talk) 15:15, 9 December 2011 (UTC)

The annoying ambivalence of domestic cats

You know the sort of thing: they come to you for a pat, you start doing so, they walk away a few paces then plop down so you have to move or lean over awkwardly to reach them... It doesn't happen every time, but it is a characteristic of every cat I've been friends with. What gives? It's like they all belong to Schrodinger - never in one state or another...

I have my theories, but rather than speculation or original research, I'd rather the answers were actual findings by someone or other - zoologists, maybe?

Thanks Adambrowne666 (talk) 03:17, 5 December 2011 (UTC)

I've noticed the same behavior. StuRat (talk) 03:39, 5 December 2011 (UTC)

We have lots of articles, like Cat behavior, Cat intelligence and Cat communication. One thing to keep in mind is that cats were domesticated somewhere around 10000 years ago, so whatever the answer is, it certainly does not have to be in terms of natural selection. Vespine (talk) 04:46, 5 December 2011 (UTC)

There's a book about this. I personally find that ambivalence one of their most appealing qualities. They make you earn their affection. Shadowjams (talk) 07:16, 5 December 2011 (UTC)

Thanks, all, but I don't feel I have the answer yet - the only thing close to one is in Cat behaviour, about their mistrust of predator species such as humans, suggesting that even when they want to be close they feel an anxious need to be distant at the same time... Still, it's not explicitly stated in the article - I'm still hoping there'll be some research somewhere someone can cite specifically on this subject... Adambrowne666 (talk) 09:28, 5 December 2011 (UTC)

I think the explanation is relatively simple. Cat fur is well known for its electrifying properties. When you stroke a cat for two long, it gets electrically charged up to the point where the cat is experiencing little electric shocks. Maybe cats feel them stronger than we do, or maybe cats are more afraid of them and therefore are particularly keen on avoiding them. In any case, for the cat it's a balance between the pleasant feeling of being stroked and the nasty feeling of getting electric shocks when being stroked too long. Hans Adler 09:40, 5 December 2011 (UTC)

Or maybe I am wrong. See www.ehow.com/how_5877799_rid-static-electricity-cat_s-fur.html for some related information that could help to check my hypothesis. (Certainly not a reliable source, but seems reasonable in this context. Due to the spam filter I can't make it clickable.) Hans Adler 09:55, 5 December 2011 (UTC)

This is a behavioral issue, not an electrical one. Searching for "petting aggression" or "status-related aggression" will provide many (but mainly low quality) sources which share the opinion that [1] cats have a limited tolerance for grooming or petting, [2] individual cats vary in their degree of tolerance; [3] cats learn quickly they can end unwanted petting by biting, scratching, nipping, or if the owner is lucky, just walking away. - Nunh-huh 12:15, 5 December 2011 (UTC)

Yeah. Cats are not quite social animals (unlike dogs/wolves). Males are strictly solitary hunters and females only gather in casual groups with their young (and only if resources and shelter are plentiful). In domestic cats that are wary of being stroked or held, this is simply the remnants of escape behavior. The cat deliberately moves some distance from you as to give him more chances of getting away if ever the stroking turns to a grip and you decide to eat him. :D While they probably trust you somewhat and definitely like being stroked, being confined is still a viscerally unpleasant situation to be in.

A lot of adult cat behavior depends on how you treated them when they were young. Lack of enough human interaction in the first eight weeks leads to adults just that little bit more distrusting of humans than kittens who did. Our article on Cat#Behavior mentions one of the reasons as behavioral neoteny. They are basically retaining childish (kittenish?) behaviors with humans who reared them and who they view as their own mothers.

And lastly, cats are individuals as well, and they do differ in behavior. Some cats are naturally affectionate, some are irritatingly aloof, and some cats get freaked out way too easily. We have two adopted strays here and while they've grown to be very comfortable around humans and like rubbing themselves against people's legs, they can't stand being held at all. Even petting them with curved hands prompts them to pull away (I suppose because it feels uncomfortably close to being gripped). -- Obsidi♠n Soul 14:39, 5 December 2011 (UTC)

If you want a cat to move away you gently 'pat' it. If you not mind it sitting on your lap then you stroke it. Why do you think it wants to stick around if your patting it? Cats don't like that. --Aspro (talk) 16:50, 5 December 2011 (UTC)

I assumed that was a typo and they meant "pet", but perhaps we need a clarification. StuRat (talk) 20:16, 5 December 2011 (UTC)

More likely an WP:Engvar issue. Patting a cat normally means stroking it gently in New Zealand, Australian (like the OP) and probably British English. See [4] [5] [6] [7] [8] [9] [10] [11]. Petting may also be used but is possibly less common. In fact the online OED specifically defines pet as 'stroke or pat (an animal) affectionately'. It doesn't mean to gently smack it or push it away as in the way you may pat someone on the back, which I guess Aspro and StuRat are referring to. Nil Einne (talk) 22:01, 5 December 2011 (UTC)

Found [12] which suggests stroking may be more common in some varities of British English but supports the idea patting is more common in Australian English. Nil Einne (talk) 22:16, 5 December 2011 (UTC)

I saw a bit of the "Nature" program on PBS, which showed a shelter with an elaborate color-coded scoring system for cats. A guy would stroke it five times - some would stay near, some would try to get away before the end of the five strokes. The ones trying to get away were deemed unsuitable for families with children. I should chase it down to reference, but somehow didn't work up the interest. Wnt (talk) 19:53, 5 December 2011 (UTC)

Thanks heaps, everyone - it seems to be a consensus now - certain cats are ambivalent between closeness and freedom, just like us... And yes, the 'pat' thing was a dialect issue - in Aus, pat and stroke are often used interchangeably - amazing detective work, Nil Einne. Adambrowne666 (talk) 05:47, 6 December 2011 (UTC)

And how about "pet" ? Can you pet a cat there ? StuRat (talk) 17:55, 6 December 2011 (UTC)

Not really; it would sound American if someone said that; it's almost exclusively a noun over here. Adambrowne666 (talk) 00:15, 7 December 2011 (UTC)

Is Down Under the land of heavy patting? -- 203.82.66.202 (talk) 03:08, 7 December 2011 (UTC)

At times, I'm glad to say. Though we have no heavy petting zoos.Adambrowne666 (talk)

And does pat mean both stroke and tap there ? (In the US it only means tap.) StuRat (talk) 04:20, 7 December 2011 (UTC)

It does, which isn't all that convenient, actually. Using the word 'stroke' usually results in someone making a double entendre - even though it's a perfectly innocent word, it seems to be used here only in a sexual context...Adambrowne666 (talk) 00:14, 8 December 2011 (UTC)

Heat Transfer (Hollow Fin)

If we have a hollow tube and its one end is at fixed temperature, then, how to calculate the temperature at other end?Anujkumardeo (talk) 06:44, 5 December 2011 (UTC)

Is it hollow and filled with air or hollow and filled with a vacuum? --Jayron32 14:20, 5 December 2011 (UTC)

Yes, to get a specific answer, we need to know more about the initial conditions. In general, this is the kind of question that can be (in principle) answered by setting up and solving a heat equation. SemanticMantis (talk) 14:24, 5 December 2011 (UTC)

Depending on the material's thermal conductivity, we may be able to ignore some of the complexity of this problem. In the simplest case, a hollow tube can be modeled with the one-dimensional heat equation. Our article presents an analytic solution. It may be reasonable to neglect the fact that the object is tube-shaped; or that it is filled with convective or flowing air. All these depend on the specific details of the problem. Nimur (talk) 19:14, 5 December 2011 (UTC)

The other end is open, however, if we can have a easy solution by neglecting the air in the tube, its ok for me. — Preceding unsigned comment added by Anujkumardeo (talk • contribs) 08:23, 7 December 2011 (UTC)

Mass of chick and egg

Does the weight of a “just laid egg” and that of a “just born chick” be the same? If no, what about law of conservation of mass?

If yes, does the chick inside the egg grow without gaining mass?Brahmarishiraj (talk) 11:08, 5 December 2011 (UTC)

Presumably you mean "just hatched chick", as a chick isn't "born", that term applies mainly to mammals. StuRat (talk) 17:51, 6 December 2011 (UTC)

Eggs typically lose about 10% of their mass during incubation, mainly due to evaporation of water.[13] --Colapeninsula (talk) 12:06, 5 December 2011 (UTC)

The simple answer to the first original question is "yes". There are minor inaccuracies such as the one mentioned by Colapeninsula. --Heron (talk) 15:53, 5 December 2011 (UTC)

And the simple answer to the second question is that the chick grows by digesting the contents of the egg. See our article on egg.--Shantavira|^{feed me} 16:05, 5 December 2011 (UTC)

Except the shell, of course, so it's mass isn't added to the chick. StuRat (talk) 16:08, 5 December 2011 (UTC)

And the waste products in the allantois, which stay behind. Wnt (talk) 19:51, 5 December 2011 (UTC)

It seems conceivable that the mass might even increase: the egg is permeable, and air can enter. A similar experiment is to measure the mass of a bean-sprout or other plant, and compare it to the mass of the bean that was originally planted. In the case of the plant, the absorbed carbon and water from the atmosphere ends up undergoing respiration and conversion to starches; the result is that the final plant weights much more than the seed it started from. I don't think the same is true for a chicken that emerges from an egg; but this would make an excellent science-experiment. Nimur (talk) 23:05, 5 December 2011 (UTC)

A fundamental difference is that the bean-sprout is a plant, which extracts carbon and water from the air (emitting a lesser mass of oxygen), whereas the chicken is an animal that would do the reverse, if anything. Mitch Ames (talk) 01:24, 6 December 2011 (UTC)

Agreed. And if the chick did expand, it would crack the egg prematurely, unless the egg was flexible and could also expand, or there was a lot of empty space inside to begin with. StuRat (talk) 17:50, 6 December 2011 (UTC)

Which program prevents sexual harassment the best?

Resolved

Which "one study demonstrated sustained behavioral change" in [14] and where can I read more about that one study? Thanks. 67.6.191.142 (talk) 11:55, 5 December 2011 (UTC)

You'd have to download/purchase/read the entire article, and that particular study will be named in the article (in the references or literature). --Ouro (blah blah) 13:06, 5 December 2011 (UTC)

Yes, I've tried emailing the author and WP:RX without luck so far. I only want to know that one fact. Is there anyone here on the reference desk who can access it and share the pertinent study citation? 67.6.191.142 (talk) 14:10, 5 December 2011 (UTC)

It's Foubert, J. (2000) "The Longitudinal Effects of a Rape-prevention Program on Fraternity Men's Attitudes, Behavioral Intent, and Behavior" Journal of American College Health 48(4):158-63. 67.6.191.142 (talk) 14:53, 5 December 2011 (UTC)

full text 67.6.191.142 (talk) 19:52, 5 December 2011 (UTC)

exact meaning of unit phon

what is the exact meaning of the unit phon in sound?Shrikant chavan (talk) 12:57, 5 December 2011 (UTC)

See Phon (not a very good article). Basically a phon measures how loud a sound is perceived to be, taking into account that human beings don't perceive all frequencies equally. In contrast, measures of sound intensity like the dBSPL only take into account the energy or pressure of a sound wave, not how humans perceive it. Equal-loudness contour shows the differences in perception of different frequencies. --Colapeninsula (talk) 13:44, 5 December 2011 (UTC)

How to progress ...?

Assume I have some technological or anything, ideas and plans, and I have no money. is incubator programs good choice for me,or it's another thing, or it depends on the program? Flakture (talk) 15:46, 5 December 2011 (UTC)

Anyone who will lend you money will want a part of the profits, unless you have generous friends or family who can lend you enough to get started. StuRat (talk) 16:11, 5 December 2011 (UTC)

It's more than just a part of the profits; people with money can and will take over the business in very short order; being the originator of an idea with no capital to bring it to fruition means very little to the venture capitalists that fund your idea. Indeed, it is rare for a broke person with a good idea to make the money on their idea that they think they are due; they rarely end up in control of the company founded to produce their idea; instead that goes to the person who either fronts the bulk of the cash and/or someone with the best business acumen who is good at getting the cash. See Bill and Scott Rasmussen who founded ESPN, but were left out of control of their own idea as Getty Oil, who fronted the cash, very quickly took control of the business. See also Eduardo Saverin, co-founder of Facebook who was edged out of the company by the venture capitalists who funded the expansion. See also Steve Wozniak who was the brains behind building the first Apple computers, but who never had much control over the company's management; that fell to Steve Jobs who probably couldn't have built a computer, but who had the head for business and marketing. There are numerous other examples. It's a catch-22 for someone with a really good idea: if you don't secure the capital, you can't bring your idea to market. In order to secure the capital, you have to give up control of your idea (and the vast bulk of the profits that come from it) to someone that does. A good rule of thumb is that the idea is basically free; you're share of the profit is the same as the share of the company you own. If your company is worth $100,000 and some venture capitalists front $10,000,000 for your "idea", then you can expect to be able to get 1% of the profit from the company. And, likely, no control over it. --Jayron32 18:18, 5 December 2011 (UTC)

I agree with Jayron's sentiment. But this shouldn't be a surprise: it's really the definition of Capitalism - venture or otherwise. "Capitalism" is predicated on the economic theory (...really, on the economic reality) that control of the means of production, via the ownership of capital, directly equates to having the upper hand in negotiations of profit sharing. A good idea is a tiny tiny fraction of a good business, and as a result, it's not really very highly rewarded in comparison to all the other aspects of a good business. Take, for example, a commodity business like PepsiCo. They sell sugar-water, grain-based snacks, and fast-food takeout. Are these "innovative new ideas"? Not in the slightest! Bread and water have been staples of the human diet since prehistoric time! And yet, by market capitalization, this company is among the largest players in the world. The reason for the success of such a business has little to do with their innovation - it's directly a result of the capital that they already own. Pepsi can own the supply-chain that delivers a very large percentage of the snacks and soft-drinks. You don't own that supply-chain: so even if you provided a comparable beverage or snack - even if you innovated and produced a revolutionary better new beverage or snack - you still don't own the means of production (in this case, the retail distribution network). The issue is even more heightened in technology-dominated industries. For example, consider operating system software. A free alternative exists that can drive all types of modern computer hardware; and yet, almost 100% of computers run a commercially-purchased operating system. This is because major capitalists own the distribution networks that provide software for computers. You can't force the owners to use something that is contrary to their own interests. In today's technology industry, the means of production include not only factories and tools, but also access to markets via economic control of critical infrastructure.

The intelligent entrepreneur must realize this limitation: you must find a way to align your innovation so that it benefits the venture-capitalist who finances your project. There is no easy way to make this happen. Various business schools across the country purport to train individuals in skills that are relevant to entrepreneurship; yet, few people actually go out into the real world and start successful technology ventures. It's more difficult than an academic problem; a classroom environment can not really prepare most people to succeed at that task. Nimur (talk) 19:08, 5 December 2011 (UTC)

Would patenting and then selling the patent work? Heck froze over (talk) 18:50, 5 December 2011 (UTC)

In theory, it could. In practice, probably not. In the modern USA, it is quite expensive to secure a patent, and most patents are awarded to companies/universities, not individuals. If you have the money and expertise to patent a technology, you likely have the money and expertise to develop your product/process. SemanticMantis (talk) 19:27, 5 December 2011 (UTC)

Strictly speaking, patents are awarded only to individuals. APL (talk) 20:59, 5 December 2011 (UTC)

I know, my question was whether Flakture could patent and then sell the patent? Heck froze over (talk) 16:32, 6 December 2011 (UTC)

Crowdfunding was missing Crowd_funding#External_links so I added it. 67.6.191.142 (talk) 23:20, 5 December 2011 (UTC) And they were immediately reverted without explanation or discussion. Imagine that! Reversion without discussion or explanation in your Wikipedia? It's more likely than you think! Anyway, they were http://kickstarter.com, http://www.thepoint.com, http://www.ulule.com, and http://www.rockethub.com. Good luck! 67.6.191.142 (talk) 23:47, 5 December 2011 (UTC)

Hello 67.6.191.142. An explanation of the revert would be good but this is not the right place to ask for that explanation. Possibly the explanation is that the purpose of an encyclopedia article is to explain the topic, not provide links to people's fav pages.

Please can you explain what crowd funding has to do with the question asked here by Flakture? Thanks, CBHA (talk) 00:41, 6 December 2011 (UTC)

The connection is pretty clear, if you have a good idea, but no capital, crowd-funding is a way to get capital without giving up control of your idea, or incurring obligations you can't fulfill.

Crowd-funding does have it's limitations, so depending on the nature of the "idea", crowd-funding may or may not be appropriate. APL (talk) 00:56, 6 December 2011 (UTC)

What Vehicle is this?

http://img.photobucket.com/albums/v43/Luigi/Choplifter%203/SPAAV.png --Arima (talk) 23:37, 5 December 2011 (UTC)

Presumably it's supposed to be a Self-propelled anti-aircraft weapon. Mikenorton (talk) 23:44, 5 December 2011 (UTC)

Didn't you ask the same ol' question a few days ago? 67.169.177.176 (talk) 23:52, 5 December 2011 (UTC)

WP:Reference desk/Archives/Science/2011 November 30#What's this SPAAV?. -- 203.82.66.201 (talk) 00:05, 6 December 2011 (UTC)

Technically speaking, that question was NOT answered because no one gave the exact Military Designation of the vehicle. --Arima (talk) 09:25, 7 December 2011 (UTC)

Itinerant has given you the military designation last time -- Self-Propelled Anti-Aircraft Vehicle. What more do you want? 67.169.177.176 (talk) 07:44, 8 December 2011 (UTC)

It doesn't appear to represent any particular model. I'd describe it as a tank modified to carry a four-barreled anti-aircraft turret, something that was quite popular in mid to late World War II. --Carnildo (talk) 02:57, 9 December 2011 (UTC)

Hm. Can anyone at least identify the Turret? --Arima (talk) 04:55, 9 December 2011 (UTC)

Oh, THAT'S what you wanted -- why didn't you say so the first time? In this case, there's no way to be absolutely sure, but it looks to me like either a Chinese Type 95 or its elder cousin the ubiquitous Russian ZSU-23. 67.169.177.176 (talk) 06:40, 9 December 2011 (UTC)

December 6

Ford Model T

December 5th, 2011 Wikipedia To whom it may concern,

I am participating in a program known as History Day. The theme this year is revolution, reaction and reform. The topic I chose was: Henry Ford Companies and Competition. I have focused on when the Model T first came out to when the newer Model A came out.

Explanation of topic; Revolution; the Model T Reaction; cars released from other companies Reform; the Model A's release

Would you be so kind to take the time to direct me to other sources regarding this topic? It would help if you could include other competition/cars that Ford Motors company had or were released in that time period. Thank you for your time and consideration. Sincerely, Ninja98.203.149.12 (talk) 01:14, 6 December 2011 (UTC)

Look at Ford Model T and Ford Model A (1903-1904). There are plenty of references at the bottom of each article. I also suggest reading the articles.

E=MC² and wind up alarm clocks

Something I've wanted to ask a physicist for some time: given that when you wind up a spring-driven alarm clock, you are storing energy in it, and given that E=MC², does its mass increase as you wind it up? I'm well aware that any increase is going to be small, but will it occur, and if so, by how much? (Ballpark figures accepted - obviously it will vary depending on the spring.) AndyTheGrump (talk) 01:35, 6 December 2011 (UTC)

I shouldn't think so. e=mc² is a description of the conversion of mass to energy, which is not what you are doing when you wind up an alarm clock. You're just storing energy when you wind something, energy that comes from your physical efforts (and, I suppose, more remotely, from the use of ATP by your muscles, which ATP is a result of your biochemistry) and not from conversion of mass into anything.- Nunh-huh 01:44, 6 December 2011 (UTC)

(ec) The short answer is yes, the apparent mass of the clock will increase. The mass increase is indeed proportional to the energy. If someone wants to measure the torque required to wind an alarm clock we could estimate the amount of energy/mass increase involved, but I don't have a wind-up alarm clock handy. For comparison, in a longcase clock, weights most often run from 3 to 5 kilograms [15] and descend through about a meter to drive the clock. Five kilograms raised one meter comes to about 50 joules of stored energy, which corresponds to a mass increase of about 5*10^-16 kilograms, or about 500 femtograms. TenOfAllTrades(talk) 01:54, 6 December 2011 (UTC)

My guess is that the energy/mass increase would be somewhat less for a wind-up alarm clock than a longcase clock, like maybe around 100 femtograms. But yes, the mass definitely increases. Red Act (talk) 02:53, 6 December 2011 (UTC)

Thanks - so it seems I was right. Actually, our mass–energy equivalence article seems to state this explicitly: "A spring's mass increases whenever it is put into compression or tension. Its added mass arises from the added potential energy stored within it, which is bound in the stretched chemical (electron) bonds linking the atoms within the spring". Trying to visualise 100 or so femtograms is difficult, but our orders of magnitude (mass) article suggests we are somewhere in the range of the mass of a small single-celled organism, if I understand correctly. Not a lot, but not entirely negligible - though I doubt you could measure it. AndyTheGrump (talk) 03:44, 6 December 2011 (UTC)

You probably couldn't measure the difference because the dust or grease you add or remove whenever you touch the watch has a much higher mass. – b_jonas 19:57, 6 December 2011 (UTC)

Unofficial record temperature

How can unofficial record temperature happen and what is the basic definition of it. Said Kangerlussuaq, Greenland have unofficial record high of 82F on June 27, 2002. The weatherbase said the maximum record is 75F. Is unofficial temperatures mistakes or error on system.--69.228.24.198 (talk) 01:43, 6 December 2011 (UTC)

"Official" weather measurements are kind of a tricky subject. In the United States, official measuring stations are those where official climate records are taken. This is almost always at an airport, with an automated station which measures temperature, humidity, wind and a few other variables at standardized heights and under carefully controlled and standardized conditions (see Automated airport weather station for more info). There are many airports and other municipal buildings such as schools which have similar weather stations which measure the same data, but which are not considered "official" reporting stations. I'm not exactly clear on the reason for this, but I presume that it is due to the fact that there is only so much money available to properly maintain instruments and perform quality control to ensure there are no biases or errors in the data. I'm not sure about the case for Greenland, but I suspect it is a similar situation: the weather station which measured the higher value was not an "official" climate reporting station, so the quality/accuracy of the data can not be guaranteed.

A related issue is that it is well-known that many "official" records from the first half of the 20th century are questionable in their accuracy; unfortunately there is a lot of political junk that goes along with revisiting old climate data, even when there are clearly problems with it. It is likely that most records from before World War II are inaccurate due to sub-standard instruments, record-keeping, and quality control.-RunningOnBrains^(talk) 02:03, 6 December 2011 (UTC)

After analyzing the data provided in your link, if you notice, the moment that the 82F value is recorded, there is a sharp spike in many of the variables; the temperature, dew point, and barometric pressure all go up substantially one hour, only to return to near the previous values in the next hour (seen more easily here). This is a very good sign that the weather station experienced some sort of error, which is why this would not be considered a record. -RunningOnBrains^(talk) 02:08, 6 December 2011 (UTC)

Wait..., can I ask again? Is there virtual difference regarding guarantee accuracy between unofficial vs. official temperatures. Does official record temperatures make higher guarantee of accuracy and less risk of error than unofficial record temperatures. I think Greenland suppose to have automated technology systems around, so I don't think the temperature records is large errors. All measurement across must be close to identical variables. Is there possibly official record temperature even after 1980 can cause similar amount of error bars?--69.228.24.198 (talk) 05:32, 6 December 2011 (UTC)

It's not just technology failures that can taint weather measurements. Exactly where the sensor is placed makes a difference. Both for temperature and wind-speed. Turbulance from nearby structures may give wind readings that are above or below the true reading, being placed near an object that warms in the sun could cause a problem with a temperature measurement. And of course the equipment itself may not be calibrated right. Even digital equipment may be precise, but wrong. Many public facilities and businesses may record the weather for their own purposes, but they may or may not pay strict, scientific attention to the equipment, how it's installed, etc. In fact, if the measurement is being done by a television station it may even be to their advantage to install the equipment in such a way that it gives more dramatic results.

All that said, I have no idea how the specific government agency that handles such things in greenland does things. APL (talk) 11:03, 6 December 2011 (UTC)

I once had the assignment of recording official US temperatures at a location. There was a little white painted standard wooden structure with louvers for ventilation. I was told that this was required, so that for instance a dark colored, poorly ventilated enclosure did not build up high temperature inside. It may have been a requirement that it be a certain height above ground, and that there be a patch of grass rather than blacktop under it. Today I suppose the instruments are electronic, and clearly there is potential for large variations due to instrument or communications errors. See [16]. Edison (talk) 15:46, 6 December 2011 (UTC)

That wooden structure would be a Stevenson screen. {The poster formerly known as 87.81.230.195} 90.197.66.22 (talk) 11:08, 7 December 2011 (UTC)

I wonder if older tradition method like ordinary mercury therometer non-technological instrument would do a more accurate job on tracking temperatures. I used to have a non-technology mercury theometer it is placed on white woods, near the patue, relative distance from whitetop concrete. I am wondering if older day theometer is still used anywhere any countries in the world like in northern Russia.--69.228.24.198 (talk) 01:13, 7 December 2011 (UTC)

Historically there was a shift from a mercury thermometer in a little white-painted louvered box 5 feet above the ground, and 40 feet from a building, over a patch of grass, to the modern digital thermometer in a white plastic cylinder high on a pole. I suggest that there may be a systematic difference in the temperatures measured by the two systems, as much so as when Chicago Illinois moved its "official weather station" from the roof of the Auditorium Building, 200 feet high, downtown near Lake Michigan [17] to Midway Airport miles inland. Chicago has temperatures "cooler near the lake" in the summer if not in the winter. Later the official weather station moved to O'Hare Airport, which records temperatures 1.9 degrees F lower than Midway. I pity anyone who has to rigorously prove global temperature change based on such "official temperature" measurement, or on any measurement with confounding variables such as the siting and enclosure of the thermometer. Edison (talk) 03:08, 8 December 2011 (UTC)

In New York City, the Weather Bureau recorded a record 99 degrees F in 1881, but when the record was broken by a 102 reading in 1918, the NY Times said the 1881 weather station was on a roof surrounded by other buildings with metal roofs, producing a reading higher than at street level, while the 1918 official thermometer was on a building which yielded lower temps than street level. The "temperature reading" must be "operationally defined." It does not exist in the abstract.

How to fit Dfd, Dwd in Trewartha climate classifications

just said Northern Russia like Verkhoyansk, Yakutsk is E climate. They are qualify is Dfd, or Dwd. If we convert it to Trewartha climate scale, what category will they fit into. Iceland should be EO, it is subarctic maritime, now we got EO which is Cfc, EC is subarctic continental that is Koppen's Dfc, Dwc. Then how about Dfd, Dwd class go into Trewartha. Can Dfd, Dwd like Verkhoyansk or Yakutsk get any of desert climates in Trewartha? Its summer frequently get humid and muggy, often get days in 80s or 90s.--69.228.24.198 (talk) 01:55, 6 December 2011 (UTC)

Both these places are classified as EC because of their dry climate (based on precipitation, not atmospheric humidity which is irrelevant for this purpose). 67.169.177.176 (talk) 02:46, 6 December 2011 (UTC)

Mung bean

I want to know some facts about nutritious value of Mung bean. 1. Is the first table in Moong_bean#Uses is for whole beans without skin , or for whole beans with skin? 2. Will I get the same amount of protein (23.86 g per 100 g) if I eat freshly prepared mung bean paste instead of whole beans? --Foyrutu (talk) 05:37, 6 December 2011 (UTC)

2) Making it into a paste shouldn't affect the protein content. However, your figure of nearly 24 grams of protein per 100 grams is far more than the 7 grams I get when I look it up: [18]. StuRat (talk) 16:56, 6 December 2011 (UTC)

This put the number from "19.5 to 28.5 percent". --Foyrutu (talk) 17:20, 6 December 2011 (UTC)

I see the problem. That was for "dry seed weight", that is, without water. My figures are for the prepared product with water, which, I believe is how you would normally eat them. If you weigh them dry, before preparing them, then you figure would be right. However, that 100 grams of dried mung beans might make some 350 grams, prepared, which is a lot to eat in one sitting (I hope you have Beano !). StuRat (talk) 17:42, 6 December 2011 (UTC)

Both red and green mung beans are usually eaten with skin, IIRC. Azuki bean paste is made from red mung bean and often contains a thin edible outer layer. ~AH1 ^(discuss!) 01:57, 8 December 2011 (UTC)

Noise pollution

What is Ld_n index for noise level measurement, what does it signify? — Preceding unsigned comment added by Intr199 (talk • contribs) 16:18, 6 December 2011 (UTC)

That is the Day-Night Average Sound Level. -- kainaw™ 17:38, 6 December 2011 (UTC)

Microwave oven frequency

I've heard that a different frequency of microwaves would preferentially warm ice over liquid water, while the current frequency does the reverse:

1) Is this true ?

2) Why don't we use that frequency ? StuRat (talk) 17:20, 6 December 2011 (UTC)

I do not believe that a different frequency of microwaves would melt ice faster. To explain why in brief, I'll be very simplistic. Water and Ice are both made of H2O molecules. They are dipole or polar - which means they are like little magnets. In the presence of an electromagnetic wave, the little magnets will try to align with the wave. But, being a wave, it keeps shifting back and forth. So, the little magnets end up shifting too. That movement is where the heat energy for everything else in the microwave comes from. The microwaves are selected to be a certain frequency that gets the most efficient wiggle out of the little magnets.

Why this doesn't work on ice? The little magnets in the ice are frozen in place. They can't wiggle as easy. It doesn't matter what frequency of microwaves are used. They still can't wiggle very well. The only argument that I'd take as a possibility is that a lower frequency might try to make the magnets wiggle slower and, in ice, wiggling slower turns out to be more efficient. But, I'd need to see a real experiment, not just some back-of-the-envelope scribbles. -- kainaw™ 17:35, 6 December 2011 (UTC)

I suspect StuRat is getting confused by the common but inaccurate claim the frequency of microwave ovens is chosen because of resonance of water molecules at that temparature. As we've discussed before on the RD and as microwave oven mentioned, this isn't true and some microwaves don't even operate at 2.4ghz. Nil Einne (talk) 18:16, 6 December 2011 (UTC)

According to our article: "Microwave heating is more efficient on liquid water than on frozen water, where the movement of molecules is more restricted." and "Penetration depth of microwaves is dependent on food composition and the frequency, with lower microwave frequencies (longer wavelengths) penetrating further." So, would lower frequencies lessen the common problem of the food being burnt on the edges with a solid block of ice in the center ? StuRat (talk) 18:45, 6 December 2011 (UTC)

There is a section about the frequency choice in the design section of the microwave oven article. In short The microwave frequencies used in microwave ovens are chosen based on regulatory and cost constraints. Vespine (talk) 01:10, 7 December 2011 (UTC)

OK. What range of frequencies are legal ? Is there any reason why the laws can't be changed to allow lower frequencies ? And what are the cost constraints ? StuRat (talk) 01:13, 7 December 2011 (UTC)

Did you read the section Microwave_oven#Design? It elaborates a bit, like saying that "legal" depends where, but I can't answer your specific questions in any more detail. Seems like microwave ovens operate just fine. If you have a problem with over cooking the outside of your frozen food, the obvious solution seems to be to lower your cooking power and increase your cooking time, rather then ask for microwave ovens to be redesigned. Vespine (talk) 00:47, 8 December 2011 (UTC)

That's exactly what I do, along with thawing foods before I nuke them or using a different cooking device entirely. But having a workaround for a problem doesn't mean I should abandon the quest to actually solve the problem. StuRat (talk) 18:50, 8 December 2011 (UTC)

My microwave is a combo microwave/toaster oven. So, I can run the toaster oven for a minute or so to melt the ice and then the microwave to cook it - all without moving the food. That is one solution. I also like it for pizza. Microwaves make limp reheated pizza. So, I microwave 1 minute and toast 1 minute and it comes out warm and crispy. -- kainaw™ 18:55, 8 December 2011 (UTC)

Interesting. I didn't know it was possible to combine those, as microwaves wouldn't work along with metal coils in a conventional toaster. How does yours manage to avoid arcing ? StuRat (talk) 19:16, 8 December 2011 (UTC)

It doesn't microwave and toast at the same time. So, the insulated coils don't arc. I'm sure there are more safeguards - but I don't really care, as long as it keeps working. I do know that it toasts only from above. If I want to ONLY toast, I put foot on a little stand to get it higher and it toasts faster. -- kainaw™ 19:18, 8 December 2011 (UTC)

Yes, a nice toasty foot can warm you up nicely on a cold day. :-) StuRat (talk) 19:34, 8 December 2011 (UTC)

Poor inventors who don't get the money/recognition they deserve

I heard that the guy who invented the computer mouse has not made much money off of his invention that is used so ubiquitously today. Are there any other examples of inventors who designed something that is used by everyone, but never got the money or recognition that they deserve? ScienceApe (talk) 19:24, 6 December 2011 (UTC)

There are probably many inventions whose inventor isn't known, because they didn't, or couldn't, patent their item. I don't think the general concept of a computer mouse can be patented, for example, but only a particular design for one. StuRat (talk) 19:32, 6 December 2011 (UTC)

Well, the mouse was patented, and no, the inventor never made any money off of his patent, see Douglas Engelbart. --Jayron32 19:44, 6 December 2011 (UTC)

One could say much the same for the inventor(s) of the computer.--Shantavira|^{feed me} 20:04, 6 December 2011 (UTC)

See Practical genius has often gone unrewarded - a knol by Zahid Ameer.

—Wavelength (talk) 20:20, 6 December 2011 (UTC)

There is one name that automatically springs to mind regarding this: Nikola Tesla. -- Obsidi♠n Soul 03:43, 7 December 2011 (UTC)

Well, some of his inventions were rather crazy, like broadcasting electricity to deliver it. StuRat (talk) 04:16, 7 December 2011 (UTC)

True. But then again during his time, it was all about crazy ideas, not to mention industrial espionage :P -- Obsidi♠n Soul 12:17, 7 December 2011 (UTC)

• Thomas Davenport (inventor) was the first inventor to power useful devices with electric motors. He gave public demonstrations of various devices powered by electric motors, but die broke and discouraged. (Wikipedia gives inappropriate credit to Ányos Jedlik), who likely did no more than replicate classroom demo models of motors he had read about, and who did not leave any writing about his motor models until 1861. Edison (talk) 16:31, 7 December 2011 (UTC)

Seems ironic that a user named "Edison" would post in this topic. Goodbye Galaxy (talk) 18:56, 7 December 2011 (UTC)

I'm looking for other good names I might use, which are not associated with the subjects of article I might contribute to. Edison (talk) 02:52, 8 December 2011 (UTC)

The blimp, and its associated wonderful derivatives, have been in rancorous relative disuse since the Hindenberg disaster. ~AH1 ^(discuss!) 01:36, 8 December 2011 (UTC)

When Dennis Ritchie died there were no headlines about him (the headlines were on Steve Jobs who I don't think was nearly as important). 99.43.78.36 (talk) 15:46, 8 December 2011 (UTC)

For sure, the death of the guy who foisted Unix upon us should have had more coverage. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:02, 8 December 2011 (UTC)

The question begged here is about what inventors "deserve". In my experience there's a very wide gap between inventing stuff, and commercialising the invention so as to make money from it. Both parts of the process are vital, and more often than not, commercialising "inventions" tkes much more time, effort, risk and capital than the inventing part. That being the case, its not very surprising that many and perhaps most inventors do not get what they "deserve". --Tagishsimon (talk) 15:52, 8 December 2011 (UTC)

Richard Trevithick invented the railway locomotive and the high-pressure steam engine but died penniless and could only be buried after a whip-round by his colleagues. As Tagishsimon says, lack of commercial accumen played a part, but he was unfortunate that the cast iron rails used for his engines couldn't cope with the weight of them - wrought iron rails were a later development. Alansplodge (talk) 16:41, 8 December 2011 (UTC)

Weak interaction

Could someone check this set of edits? I knew a little when I wrote the article (enough to follow what I was being told) but less now. Grandiose (me, talk, contribs) 19:35, 6 December 2011 (UTC)

Looks correct to me. Dauto (talk) 19:51, 6 December 2011 (UTC)

How do we know the speed of light is constant? Part 2: Gravity Wells

So I came across this conversation in the archives which I can't actually remember if I started (though it sounds like the kind of thing I'd ask): [19]. Okay, so we know that the speed of light is the same because other stars would look hella different if the rules of physics there were completely different (as they would be with any vast changes to the speed of light). So here's a question for you: how would we go about finding out if the speed of light remains constant *outside of a gravity well*? There's not a whole lot to observe in the big spaces between stars. So what sort of experiment would be required to answer my question? (I might be thinking about the Pioneer anomaly a little here...) --Brasswatchman (talk) 21:04, 6 December 2011 (UTC)

Much of modern cosmology is predicated on the assumption that the rules of physics that apply here on Earth are the same rules of physics that apply across the entire universe. For example, significant effort has been spent studying the cosmic background radiation, looking for two things: inhomogeneity and anisotropy. So far, there doesn't seem to be a whole lot of either. In simple terms, this means "as far as we can see, the physics that governs our universe is uniform everywhere."

If you could first contrive a theory that would differentiate between a constant- and non-constant speed of light, and then, secondly, deduce some observation that could validate that theory, and thirdly, if you spent many years of your life scanning astronomical observations seeking observational evidence of the first two parts... well, you'd be a cosmologist, and you could probably be published in a prestigious journal. Nimur (talk) 22:54, 6 December 2011 (UTC)

I'm aware the idea is far-fetched. Just humor me. Consider it as a thought experiment. Let's go with your point about cosmic background radiation -- if the speed of light did change outside of gravity wells, what would the effect on background radiation look like? --192.234.2.90 (talk) 23:18, 6 December 2011 (UTC)

We do have the article Variable speed of light, though it doesn't appear to address your exact scenario. Tangentially related are our articles Scharnhorst effect and Pioneer anomaly. -- 203.82.66.200 (talk) 23:52, 6 December 2011 (UTC)

The "big space" between galaxies is filled with ionized gas which has been observed. A change in the speed of light would affect their observed spectral lines. Also, the pioneer anomaly has been explained as caused by thermal radiation pressure. Dauto (talk) 04:24, 7 December 2011 (UTC)

Good point, Dauto. I hadn't thought of that. --Brasswatchman (talk) 22:28, 8 December 2011 (UTC)

An aside: how do we know that the speed of light is the universal constant, and not the speed of some other particle such as a tachyonic neutrino? The properties of a neutrino are very different from also-massless photons, as neutrinos can travel through most solid matter and don't (AFAIK) have frequencies. ~AH1 ^(discuss!) 01:33, 8 December 2011 (UTC)

Neutrinos are massive particles... and all matter has a frequency (see matter wave). The frequency of a neutrino is E/h. --130.216.55.200 (talk) 22:52, 8 December 2011 (UTC)

Killing me softly ?

I just saw a movie where a murder was committed by slowly pulling a car forward towards the victim who was caught against a fence in a dead end. I was wondering if a car without any speed to it would have the force/pressure required to crush someone to death (I expect that less force would be required to prevent breathing and cause asphyxiation eventually, but that's not what I'm asking about here). The car appeared to be on level ground, with good traction, and caught the victim under the ribs. It was a large car, but I also wonder if a small car could have done the job. StuRat (talk) 21:41, 6 December 2011 (UTC)

In the "yuppie" area of where I live, about 5 years ago according to my terrible memory, there was a road rage incident in which a man in an SUV followed a lady in an SUV into a parking lot. From a very close distance (no running start), he pinned her between the SUVs and killed her. I'm Googling for the old news article to get details, but I haven't found it yet. -- kainaw™ 21:49, 6 December 2011 (UTC)

Seems a question of "starting Tractive force," though the article talks mostly about locomotives. An auto can exert enough starting tractive force to climb up a pretty steep ramp, so on level ground, it could likely exert many hundreds of pounds force. I would expect that a typical car moving forward quite slowly from a standstill could crush the life out of a person, if it was on dry pavement and had normal traction. If it were on ice, the chances of survival would be greater as soon as the tires started to spin. We're talking hundreds of horsepower in some cases. Edison (talk) 21:54, 6 December 2011 (UTC)

Would hundreds of pounds of force be enough to crush you to death ? How much was needed to press a "witch" to death in the good old days ? StuRat (talk) 21:57, 6 December 2011 (UTC)

Crushing (execution) has numbers. WHAAOE. --Jayron32 23:39, 6 December 2011 (UTC)

That lists weights of 400 to 700 pounds, but from the length of time required to kill, it sounds like that was not enough to actually crush them, but only kept them from breathing. StuRat (talk) 00:40, 7 December 2011 (UTC)

I'm fairly certain an automobile can exert well over 700 pounds of force, else how would it move itself... --Jayron32 00:45, 7 December 2011 (UTC)

Rolling resistance? I definitely don't disagree with the other statements, but you definitely do not need nearly 700 lbs of force to start a car moving. I weigh 180lbs and I can get a car moving, on flat ground in neutral of course. Vespine (talk) 00:50, 7 December 2011 (UTC)

A car never has to lift itself vertically, so there is no need for it to be able to produce a force greater than its weight. --Tango (talk) 00:52, 7 December 2011 (UTC)

A car often has to climb a ramp, thus "lifting itself" to an extent based on the angle. 15 degree ramps are common, and a compact car weights 3000 to 4500 pounds For a 15degree ramp and a 3000 pound car, the vehicle has to exert a force of 3000 sin 15 degrees = 776 pounds parallel to the ramp to move. This is not to say the car couldn't climb a steeper ramp, since 20 degree ramps are sometimes used by builders who ignore cars bottoming out and scraping at the top or bottom, of sliding in winter. For a 20 degree ramp and the same car, the force would be 1026 pounds. Edison (talk) 16:26, 7 December 2011 (UTC)

Some hills where I live have a slope greater than 20 degrees, and most cars have little difficulty in climbing them in low gear. Vehicles with a low-range gearbox (such as Jeeps) can climb much steeper slopes if there is sufficient traction. Dbfirs 22:41, 7 December 2011 (UTC)

I don't think being pinned by an auto is analogous to the way they crushed witches. In the former case, the force is concentrated by the bumper; in the latter, the force is distributed by the plate. Think in pounds per square inch. SemanticMantis (talk) 02:28, 7 December 2011 (UTC)

The OP specifically mentions the victim being pinned under the ribs, where a number of your vital organs reside. It's easy to imagine the force needed there to fatally damage something to be far lower then the force that might be required to crush a whole person. Vespine (talk) 03:20, 7 December 2011 (UTC)

Cat's Eyes

Why do the pupils of large cats not contract to the same vertical slits as smaller (housecats) cats? I guess I'm asking if anyone knows the different evolutionary pressure that these small cats underwent to get such a distinctive pupil shape.71.232.14.6 (talk) 23:50, 6 December 2011 (UTC)

Oddly enough, it seems the one body part that the Wikipedia article Cat anatomy does not cover is the eyes. Hm. --Jayron32 00:01, 7 December 2011 (UTC)

I found a pretty decent sounding explanation on this website. Vespine (talk) 00:23, 7 December 2011 (UTC)

Well, I didn’t find that link very informative. Vertical slits, in my view (no pun intended) would allow better 'horizontal' resolution and depth of view. This fits in better, with the type of visual attributes that such a cat would need in order to hunt smaller pray. Think of it, as evolutionary built in astigmatism.--Aspro (talk) 01:09, 7 December 2011 (UTC)

Goat eyes

It's the opposite. Horizontal pupils (such as in bovids, anurans, kangaroos, bottlenose dolphins, and cephalopods) give them very good peripheral vision and motion detecting capabilities especially in flat environments (like the African savannahs or the sea floor). They function as a sort of wide-angle lens and don't exactly give them better depth perception (especially since animals which possess such eyes do not have binocular vision)

Vertical pupils, on the other hand, are simply the contracted pupils of hunters which operate at night or at low-light environments (like domestic cats, some lizards, some snakes, harp seals, lorises). It's the most efficient way of collapsing very large pupils and enable them to still see in full sunlight. Fully expanded, the pupils of these animals are actually round (think Puss-in-boots in Shrek). Compare with human eye dilation, which is achieved by the radial iris sphincter muscle. The latter is much more limited in the sizes it can contract to or attain when dilating.

Both eye types have repeatedly evolved in animals with the same ecological requirements, an example of convergent evolution.-- Obsidi♠n Soul 01:35, 8 December 2011 (UTC)

I heard somewhere that amongst vertebrates with slit pupils, the slits are more often vertical amongst predator species and horizontal amongst prey species, but our pupil article has nothing to say about slit pupils beyond acknowledging their existence amongst "some cats". The reference given there [20] does mention in its abstract that "Slit pupils were only present in animals having multifocal optical systems. Among the felids, small species have multifocal lenses and slit pupils, while large species have monofocal lenses and round pupils. The Eurasian lynx, a cat of intermediate size, has an intermediate eye design. The functional significance of the absence of multifocal optical systems in large felids remains mysterious, because such systems are present in other large-eyed terrestrial vertebrates. " -- ToE 02:05, 7 December 2011 (UTC)

Yes, the propensity is there but it is not absolute. Some vertebrate predators have horizontal pupils as discussed above. Frogs, for example, rely on detecting movement and reacting quickly to catch prey. They don't need the absolute focus and clarity of binocular vision and vertical pupils.-- Obsidi♠n Soul 01:43, 8 December 2011 (UTC)

December 7

Isn't sputum full of proteins?

Should evolution work towards more acceptance of directing sputum into the stomach? Imagine Reason (talk) 02:18, 7 December 2011 (UTC)

Evolution is not an intelligent being. It doesn't work towards anything. -- kainaw™ 02:28, 7 December 2011 (UTC)

Not all proteins are good for consumption. Yes, there are good proteins, but, for example, salmonella isn't something you want to direct into your body. -- kainaw™ 02:38, 7 December 2011 (UTC)

What do you mean "more acceptance"? Do you mean a better biological mechanism for directing sputum into the stomach, or social acceptance of eating sputum? --Colapeninsula (talk) 10:36, 7 December 2011 (UTC)

Well, we don't like the taste of sputum, and everyone just spits it out if able. Imagine Reason (talk) 23:51, 9 December 2011 (UTC)

Yeah, most saliva does end up in the stomach rather than being spat out or dribbled. Graeme Bartlett (talk) 12:11, 7 December 2011 (UTC)

Copernican Model

It seems like Copernicus' hypothesis of a heliocentric universe wasn't really supported by any observations (pre-Galileo). That is, all observations of the universe were adequately explained by the Ptolemaic model. So why did many scientists prefer the Copernican model? — Preceding unsigned comment added by Trimbler00 (talk • contribs) 06:47, 7 December 2011 (UTC)

Well, for one, simpler is better — it did away with the need for epicycles and other complicated reasoning for the bizare apparent motion of the heavenly bodies. Plasmic Physics (talk) 08:37, 7 December 2011 (UTC)

Copernicus' model had epicycles. It was Kepler who did away with them by concluding that planets moved on elliptical orbits. If I'm not mistaken, the Copernican model was not even better at describing the observations than the Ptolemaic model. Kepler's model was. --Wrongfilter (talk) 09:06, 7 December 2011 (UTC)

The Kepler model was not even strictly heliocentric because the Sun is located at a focal point rather than at the center of the elliptical planet orbits. The Newton model doesn't have a center at all. Bo Jacoby (talk) 09:19, 7 December 2011 (UTC).

The truth is most scientists did not prefer it until Galileo's observation of the phases of Venus, which is the first piece of anything that was totally incompatible with the Ptolemaic model. Even then it took a long time for heliocentrism to really catch on. The discussion here is pretty good. It's also worth noting that there were other alternatives between pure Ptolemaic and pure Copernican — even after Galileo, many astronomers (notably the legions of Jesuit astronomers employed by the Church) preferred the Tychonic system, which at the time was observationally indistinguishable from a heliocentric model. The few scientists who did support Copernicanism, without much evidence, did so for philosophical reasons, not scientific ones, to put it very simply. Sometimes philosophical reasons turn out to be right. Sometimes they don't. Kepler liked heliocentrism because he believed the Sun was the most powerful thing in the universe. That's not correct at all, but it did lead him down a "more correct" path from the view of the present (even if much of his reasoning is completely batty). (Kepler in general is a good case study in how a completely insane set of beliefs can still get one to extremely useful science.) --Mr.98 (talk) 13:31, 7 December 2011 (UTC)

A large part of the answer (why some people preferred the heliocentric model without scientific reason) is Hermeticism. This is also largely why the heliocentric model (or at least most of the works arguing for it) was suppressed by the Church from shortly before Galileo (who certainly had many hermeticist contacts, and used hermetic terminology) started arguing for it. And given that the Hermeticists believed that widespread adoption of the Heliocentric model would be followed by complete rejection of the Church, and that this had actually already led to violence, one can at least sympathise with why the Church would want to suppress it, for a while. 86.164.79.174 (talk) 09:41, 8 December 2011 (UTC)

Powering civilization with something other than electricity

Are there any other potential candidates that may replace electricity? ScienceApe (talk) 07:04, 7 December 2011 (UTC)

Would you care to explain? I honestly have no idea what you are considering. Plasmic Physics (talk) 08:33, 7 December 2011 (UTC)

Burning wood and using (water- or wind-) mills. --Lgriot (talk) 09:00, 7 December 2011 (UTC)

If that is indead what ScienceApe is considering, then no. Plasmic Physics (talk) 09:05, 7 December 2011 (UTC)

You only have to look back 100 years to see that we managed very well before the widespread use of electricity. See energy development.--Shantavira|^{feed me} 09:33, 7 December 2011 (UTC)

Photonics may replace electronics in some applications, but it is still dependent on electricity.

I guess potentially you could use anti-electricity where positrons in anti-matter wires replace electrons, but it seems kind of pointless.

On the other hand, clockwork was very once popular; the clockwork gramophone is the nearest mechanical equivalent of the iPod, and you can also make clockwork timepieces, toys, and even sort of cars[21]. The hand-cranked mechanical adding machine is similar. --Colapeninsula (talk) 10:48, 7 December 2011 (UTC)

You can distribute power mechanically via drive wheels, belts and chains. This is quite inconvenient and dangerous. An alternative might be pneumatics - just provide pressure lines, and connect your pneumatically driven appliances. In theory, you could even generate heat (via friction), and building a fridge should be very easy (just use the cooling effect of gas expansion). You can have "fuses" to protect you from overpressure, and also to protect the network from someone drawing too much pressure from the system. I'm not convinced all this is practical for all of civilisation, but its fun as a thought experiment. --Stephan Schulz (talk) 11:13, 7 December 2011 (UTC)

Vladimir Nabokov's novel Ada or Ardor: A Family Chronicle is set in alternative universe in which hydraulics has replaced electricity. I don't think that it would actually work, though. Deor (talk) 13:36, 7 December 2011 (UTC)

Lighting was the killer ap for electricity, not sure how hydraulics would provide that. 75.41.110.200 (talk) 16:21, 7 December 2011 (UTC)

Before electricity there were widespread gas networks used for gas lighting, although it's not as convenient as electricity. --Colapeninsula (talk) 17:58, 7 December 2011 (UTC)

I'm trying to think outside the box a little. Like if we were to encounter an alien civilization, would they power their civilization with electricity? Is this the only way? Is there anything else that would work? If we were to make a robot that could perform all of the basic functions that a human could perform (walking, running, grabbing, pushing, pulling, etc), it would be powered by electricity. But animals can do those things being powered by ATP... I think. Is that more efficient? Can you run an entire civilization on ATP? Stuff like that, just brainstorming what else might be possible. ScienceApe (talk) 16:21, 7 December 2011 (UTC)

In Neal Stephenson's lovely novel, The Diamond Age, the only infrastructural feed into most residents is a supply of base matter that universal nanotech assemblers can then turn into whatever one might need. It's an interesting idea. It wouldn't get rid of a need for electricity, but it seems to fit into your thinking outside the box idea. --Mr.98 (talk) 17:29, 7 December 2011 (UTC)

I like Steampunk. I have seen many non-electric power transmission systems used in industry to transmit power from a vehicle to a tool (see Hydraulic rescue tools, or from a compressor to a machine elsewhere in a plant, or to store energy in a device. Hydraulics is an excellent alternative to electricity for many applications at the present time, to transmit power for a few meters. See Hydraulic power network. Hydraulic motors work very well from hydraulic lines, with excellent power at a small size and weight compared to electric motors. Many cutting tools use a hydraulic line to power an extremely powerful but small and lightweight tool, where an electric motor or solenoid would be massive to provide the same force or torque. Some Phonographs in 1890 had a water motor, with a hose running from the tap and another back to the sink. The energy ultimately came from the city water works. Springs (wound by electric motor, or by hand crank during a power outage) still provide a large amount of stored energy, even in electric substations, to trip and reclose breakers. Everything still performs its current interrupting or reclosing function even if all the electricity abruptly fails. Compressed air is also used as stored energy on high voltage circuit breakers to provide multiple trip and close operations during a power interruption, without relying on a station battery which is all too often impaired. Oil hydraulic lines are less subject to freezing than the moisture in compressed air lines. Cables convey power from the engine of a crane to loads way up in the air, and commonly operate elevators, with reels typically operated by electric motors, but pre-1900 there were steam powered cable operated elevators in some large buildings. Rotating shafts work very well, allowing one prime mover (water wheel, diesel, steam) to power the big overhead shaft with each tool or machine in a factory having its own drive belt. These powered industry worldwide for decades, from early in the industrial revolution through perhaps the 1920's, though small electric motors on individual machines or tools proved to be safer and possibly more efficient when only part of the machines needed to operate. Steam power certainly has been useful, but for more than short distance it would require advances in insulation to reduce the heat loss and condensation in the supply lines. A 1904 article compared several power transmission systems for use in mines to drive pumps, and stated 70% efficiency for electrically driven pumps, 20% to 40% for compressed air, less than 55% for steam power pumps in main mineshafts. Steam was still in wide use, generated at the surface and sent down insulated lines to the pumps, which then raised water hundreds of feet. A 1897 book "Hydraulic machinery" by Robert Blaine compared losses for various power transmission system for 1 to 20 miles. Considering 1000 horsepower sent in, the loss in a 20 mile run for hydraulic (water under pressure) (at 700 psi) is 25.4%; for electric (at 2000 volts) is 31.2%. Electricity did better at 2000 volts than at 700 volts, where it had a 95.2% loss. Hurrah for transformers! Electricity wins for long distance transmission if the voltage is raised high enough and the current is thus made small enough to minimize losses. But the book cited says (Page 369) "However, in towns, and for comparatively small distances, the hydraulic system compares very favourably with any other as regards efficiency and supplies probably the best means of working lifts, cranes and other machines of that kind." A practical objection to long distance hydraulic transmission is the large number of joints which have to be maintained free of leaks, the bulkiness and cost of the pipes, and the danger of the water freezing. An 1886 reference compared power transmission by electricity, compressed air, water acting as a hydraulic fluid, and cables carried on overhead pulleys. Assuming a steam engine as prime mover at the sending station, the hourly cost (per horsepower) of 100 horsepower at 20 kilometers was calculated at 0.480 franc for electricity, 0.997 franc for hydraulic, 0.666 franc for compressed air, 1.321 franc for elevated drive cables over pulleys. Cables and pulleys were said to be the most cost-effective system for up to one kilometer, where the costs were 0.202 for electricity, 0.272 for water under pressure, 0.347 for compressed air, and 0.165 for cable over pulleys. Steam and rarified air were said to be ineffective for long distance. Edison (talk) 21:49, 7 December 2011 (UTC)

Well, hypothetically, you only have a few choices; to "power" something you need energy. Here's a non complete list of Forms of energy or maybe even Fundamental interaction? This shows that gravity is probably out, being so much weaker then electromagnetism, but Strong interaction could be a contender being a couple of orders of magnitude more. I suppose that would mean that every device has a nuclear reactor in it, but to this date, all our nuclear reactors do is convert energy to electricity by various means. I don't know how you could harness and use strong force more directly, but I suppose I wouldn't assume it's impossible, given some crazy futuristic technology. Maybe appliances in 500 years time run directly on fusion reactors. Vespine (talk) 00:29, 8 December 2011 (UTC)

I guess maybe you could replace computers with something like the Analytical Engine... Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:28, 8 December 2011 (UTC)

Pneumatic tubes seem like good candidates for transport. ~AH1 ^(discuss!) 01:23, 8 December 2011 (UTC)

A few months ago on Ref Desk I cited the history of pneumatic tubes. There were underground tube systems in large cities in the late 19th century, between freight terminals and post offices, moving many tons a day of such mail pouches as would fit in the tubes, far faster than surface transit, and for fair distances of perhaps a mile, if memory serves. But such a system of tubes is an information transmission system, more akin to an "internet" than to a power transmission system, unless you subscribe to the view than "knowledge is power." Edison (talk) 02:40, 8 December 2011 (UTC)

(un-indent) In case nobody noticed, the OP specifically asked about what could REPLACE electricity in the future -- so the defining criteria is not that it be merely an ALTERNATIVE to electricity, but that it be BETTER than electricity. Of the ideas I've seen in this thread so far, none meet this criteria (with the possible exception of positrons and/or the strong nuclear force). 67.169.177.176 (talk) 07:58, 8 December 2011 (UTC)

Soybean protein

I have a question regarding soybean protein. We know 100 g soybean contains 36.49 g protein. But a popular soy brand in India called Nutrela, manufactured by a BSE and NSE listed company, claims their brand of Soybean contains 54.2 g protein per 100 g. How this can be possible? Or is it Textured vegetable protein? --Foyrutu (talk) 08:53, 7 December 2011 (UTC)

As far as I can make out, they do not make the claim for soybeans, but for a processed item that looks like a breakfast cereal to me. If you process the food, you can of course vary the proportions of different constituents. They also claim low-fat, so they probably removed the 20% soy oil - that alone would up the protein content to 50%. --Stephan Schulz (talk) 10:02, 7 December 2011 (UTC)

Thanks, I get it now. --Foyrutu (talk) 11:50, 7 December 2011 (UTC)

They could have dried the soybeans. In that case, the resulting product contains much less water than the soybeans, so its mass is significantly less, but the protein content doesn't change. That means your figure of protein content per unit mass will increase. – b_jonas 13:32, 7 December 2011 (UTC)

Update: ah, but Stephan Schulz's solution seems more likely, as soybeans don't contain too much water according to the table you've linked to. – b_jonas 13:33, 7 December 2011 (UTC)

conservation of momentum in inelastic collisions..

Why?I mean, if the collision makes a sound, it means that the particles of the masses that collided exerted a force on the air molecules, and by Newton's third law, it means that they exerted a force on the bodies, too, so the momentum is not conserved, since there's external force...--Irrational number (talk) 09:08, 7 December 2011 (UTC)

Don't forget, momentum is only conserved in a closed system. Plasmic Physics (talk) 09:12, 7 December 2011 (UTC)

That means you have to include the momentum of the air molecules in your momentum conservation law 157.193.175.207 (talk) 10:47, 7 December 2011 (UTC)

On principle, you only collide spherical cows in a vacuum. But even in practice, the sound may carry away energy, but little momentum. Sound is a longitudinal wave, it does not involve a permanent linear movement of particles. --Stephan Schulz (talk) 10:06, 7 December 2011 (UTC)

And the sound propagates in all directions, so any momentum carried by the ways (already negligible anyways) will be cancelled by the sound wave sent in the opposite direction. Dauto (talk) 15:58, 7 December 2011 (UTC)

But, since the question specifically does ask, momentum is carried by air. The continuity equation for gas flow is constrained by conservation of momentum. If you follow this mathematical exercise through to its logical conclusion, you rederive the gas equations (the Navier–Stokes equations, or one of the variations of those formulas). The Wikipedia article shows an analytic derivation of Navier-Stokes with attention to the conservation of momentum. This physical term contributes to the equations anywhere you see a velocity-flux ($\nabla {\vec {\mathbf {v} }}$).

It is very rare that a practical solution for collision between two solid bodies requires consideration of momentum in the gas. I can think of two places where you do care about this: the analytical solution of the combustion chamber dynamics inside an internal combustion gasoline engine, wherein a chemical reaction causes a gas expansion and then drives a mechanical piston - that's an inelastic collision between expanding gas and the cylinder head; or the analytic solution of combustion chamber dynamics inside a rocket engine, wherein gas momentum is so great that it drives the entire vehicle. Nimur (talk) 17:37, 7 December 2011 (UTC)

well my point was any reduction in the mechanical energy requires the interaction of the system with it's environment, and thus forces will be exerted on the system in the process, so it's not accurate to say we have conservation of momentum where there isn't conservation of energy, now i know that i'm wrong, because i reached a wrong conclusion, but i don't know WHY(OP).....--95.82.51.215 (talk) 17:26, 7 December 2011 (UTC)

There are many situations in which the total momentum of a system is conserved (to a very good approximation), even though lots of energy is lost to the surrounding environment. All that is necessary is that the loss of energy occurs as a result of forces that are equal and opposite and act for the same time, or, more generally, forces that have a vector average of zero when integrated over time. See Newton's second law. Dbfirs 19:05, 7 December 2011 (UTC)

For one thing you can have loss of mechanical energy without any external forces at all. Internal forces might convert Mechanical energy into heat. Another thing is that the momentum of external forces could cancel each other even if all those forces are exerting a net negative work and removing energy. Dauto (talk) 19:39, 7 December 2011 (UTC)

Conservation of energy and conservation of momentum are different things. The momentum is usually lost to other factors, such as friction, but an object falling onto a surface without any rebound (ie. plasticene) would lose all of its momentum yet feel only half the impulse of an elastic object rebounding to its original height (minus air resistance). ~AH1 ^(discuss!) 01:13, 8 December 2011 (UTC)

spin is taken as a quantum number

what is the reason to take spin quantum number?what does it physically stand for? — Preceding unsigned comment added by Bidhanism (talk • contribs) 14:18, 7 December 2011 (UTC)

It stands for the intrinsic angular momentum of the particle. That's analogous to the classic angular momentum of a spinning object - hence the name. Dauto (talk) 15:55, 7 December 2011 (UTC)

Bit off topic, but you may be interested in Heisenberg uncertainty principle. For some parameters you can't measure both simultaneously. ~AH1 ^(discuss!) 01:09, 8 December 2011 (UTC)

capilary rise

when a tube of insufficient length is immersed in a liquid,will the liquid overflow? — Preceding unsigned comment added by BENADIK (talk • contribs) 15:54, 7 December 2011 (UTC)

No, that would violate conservation of energy. Dauto (talk) 16:04, 7 December 2011 (UTC)

That does happen with superfluids. See the third paragraph of Superfluid#Background. Red Act (talk) 16:27, 7 December 2011 (UTC)

You need to heat the superfluid to provide the needed energy. Dauto (talk) 16:29, 7 December 2011 (UTC)

You need to apply heat to get the fountain effect, but my understanding is that a Rollin film will form without needing to apply any energy from an external source. Energy is conserved, because the increase in gravitational potential energy is counterbalanced by the decrease in potential energy associated with the adhesion between the superfluid and the surface. Red Act (talk) 17:12, 7 December 2011 (UTC)

Yes, that's correct. Dauto (talk) 18:40, 7 December 2011 (UTC)

Pulling Teeth

When teeth are pulled, don't at least some alveolar bone get destroyed via microfractures/broken bone?Curb Chain (talk) 18:36, 7 December 2011 (UTC)

Dentists wouldn't normally pull a tooth which is well rooted. The teeth which are pulled are likely already separated, due to infection, etc. StuRat (talk) 18:24, 8 December 2011 (UTC)

Yes, they normally wouldn't. Infact, they would exhaust all other remedies before they would pull teeth, because doing so is a last resort where all other remedies have failed. My question is:

Consider the molar: the alveolar bone is surrounded by concave roots. Does this alveolar bulge get fractured (in some way) when it gets pulled?Curb Chain (talk) 20:34, 8 December 2011 (UTC)

I would think that wisdom teeth are often pulled while well-rooted. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:06, 8 December 2011 (UTC)

When I've had teeth out, sometimes small fragments of bone have worked their way out of the gum in the following weeks. --Kurt Shaped Box (talk) 23:15, 8 December 2011 (UTC)

I had my wisdom teeth out earlier this year at 31 years old and the dentist said not to put it off any longer, given that healing may be more complicated the older I get. He mentioned the very reason: some bone would come out with it, and that would take longer to heal. And, lo and behold, he told me post op that he had to chisel out small bits of bone to get teh wildly crooked wisdom teeth out. Mingmingla (talk) 23:48, 8 December 2011 (UTC)

contact lenses and acid

Why is it more damaging/dangerous to get acid in your eyes if you're wearing contact lenses? I've heard this stated before as the contact lenses will melt onto the cornea? 86.7.42.12 (talk) 19:23, 7 December 2011 (UTC)

Probably because the acid can get trapped under the contact lens.Curb Chain (talk) 19:24, 7 December 2011 (UTC)

Basicly what Curb Chain said. When you get a contaminant in your eyes, the first thing that happens is that tears are produced which help dilute the contaminant and then your blinking can wipe it off of the surface of the eye. Contacts hold onto and concentrate the contaminant, preventing your tears from diluting it, and blinking doesn't move the contacts. That's why you shouldn't wear contacts when working around certain chemicals (not just acids). --Jayron32 19:31, 7 December 2011 (UTC)

So could you just remove the contact lens and rinse the eye as you would with an acid-splashed eye that wasn't wearing contact lenses? For some reason I've heard that it becomes impossible to remove the lens, but I'm dubious of this. 86.7.42.12 (talk) 19:39, 7 December 2011 (UTC)

I am a certified Emergency Medical Responder and I have never heard of this. The contact lens should be removed if you get chemical in your eye. It should be flushed. Who told you this and s/he is probably wrong.Curb Chain (talk) 20:07, 7 December 2011 (UTC)

Acid-splashed eyes tend to spasm shut, which would make it harder (NOT impossible) to remove the contact lens. Also, chemical burns happen very rapidly (15 seconds or less), so by the time the lens is removed, it's very likely that permanent damage has already occurred. 67.169.177.176 (talk) 08:03, 8 December 2011 (UTC)

The above IP is correct. I recently had a scare caused by my own stupidity where I forgot to put my eye protection on after a break from my experiment, and ended up getting some sodium oxide in my left eye. I immediately rinsed out my eye and attempted to remove my contact lenses, but I found it quite difficult to keep my eyes open wide enough to do so. Nothing happened to the lenses, but my eyes were so badly irritated I could not keep them open. I got extremely lucky in that I only ended up with a very minor burn which was not on my cornea and a nasty case of chemical conjunctivitis. But you can be damn sure I'm not making THAT mistake again. -RunningOnBrains^(talk) 08:20, 8 December 2011 (UTC)

Even so, given the rapid timescale of the burn, is there a chance that the contact lens actually shielded your cornea from the burn? Wnt (talk) 04:03, 9 December 2011 (UTC)

Don't try testing this at home though I secretly pray that you'd be so stupid as to actually try it at home and burn your eyes out with Drano, you green fanatic... 67.169.177.176 (talk) 07:05, 9 December 2011 (UTC)

Where did that nasty comment come from? -- User:Dauto 14:59, 9 December 2011

From a Californian who has escaped the block-hammer so far, but this is going too far and I've asked for admin assistance. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:15, 9 December 2011 (UTC)

Actually, I have been blocked once before under a different IP, for upholding the truth in an edit war on the article Extermination through labor. And as far as this matter: I want to qualify that I did NOT intend this comment as a threat, and would NOT actually do this to Wnt even if I had the opportunity (but on the other hand, if he did this to himself, either accidentally or deliberately, I likewise would not lift a finger to help him). And BTW I don't give a flying fuck if you block me a second time -- I can get by without Wikipedia just fine, thank you.67.169.177.176 (talk) 00:31, 10 December 2011 (UTC)

Water collecting on paper towels

A hopefully simple question. When, you clean up a spill with paper towels, where do the liquid molecules go? It's obvious their atoms don't just fuse together, but are the paper towel molecules spaced out enough that the water molecules can fit inside the spaces of the paper molecules? 64.229.180.189 (talk) 20:29, 7 December 2011 (UTC)

Pretty much. The water molecules simply fill the spaces in the paper towel, which are substantial. Paper towel fibers are also flexible and can thus expand to hold more water than may be readily apparent from the dry towel. --Jayron32 20:41, 7 December 2011 (UTC)

Unfortunately, our paper towel article does not address the mechanism beyond stating that they are an "absorbent textile" which "soak up water because they are loosely woven which enables water to travel between them, even against gravity". Note that the water doesn't fit inside the the space between individual paper towel molecules as much as it is drawn inside much larger structures of the paper towel. Capillary action (section: Examples) mentions the wicking action of paper towels. Does anyone here know what the approximate size of the structures involved are, an how much larger they are than individual molecules? Also, in a strict chemical sense, are "super absorbent paper towels" really absorbent, or would that require the inter-molecular action the OP suggested? -- ToE 00:03, 8 December 2011 (UTC)

Even tightly woven fabric can be quite waterproof so I really don't think there's any "in between molecules" happening there. I think it would have much more, if not all to do with Capillary action as noted above. For illustration steel wool can soak up a considerable amount of water even though the actual steel fibers would obviously not be absorbing any water. Vespine (talk) 00:12, 8 December 2011 (UTC)

December 8

Why would you tell yourself the obvious?

An example: you go to the basement for some reason you forgot the moment you got there and say literally and out loud to yourself: "why did I go here?". Why would you do that? Your brain obviously already knew it forgot the reason, and still it's somehow urged to take all the trouble to get the lungs, mouth and ears into action to get exactly that message. (I do hope I'm not the only showing this bizarre behaviour, otherwise consider saying "Ouch" or more blasfemous terms when there's nobody around). Possibly related is that when I encounter a hard problem when programming it often helps to get a collegae to explain the problem to and finding the cause by the explaining itself. Any clues for further reading? Joepnl (talk) 02:30, 8 December 2011 (UTC)

I have never done anything of the like, but I know people who do. I know one who does it to the extreme. In my opinion, her brain is incapable of processing thoughts if she isn't speaking everything that she is thinking. So, I figure there is a certain level to which you find comfort in hearing your own voice. For me, I have no use for it. For the woman I mentioned, she is obviously uncomfortable if she isn't hearing her own voice (yes, she continues to talk to herself without pause even when she is alone in her office - new workers ask who she is talking to in there until they realize her mouth doesn't stop moving). I believe that most people are somewhere between the two extremes. All in all, it is a comforting thing. -- kainaw™ 02:34, 8 December 2011 (UTC)

I asked a question that explicitly said that it's about talking to yourself without anyone hearing it so your rant about this person is totally useless. I do feel sorry for the woman you mentioned for knowing someone like you. Joepnl (talk) 03:15, 8 December 2011 (UTC)

Maybe intrapersonal communication would help you out. Dismas|^(talk) 03:01, 8 December 2011 (UTC)

That is interesting, thanks! Joepnl (talk) 03:17, 8 December 2011 (UTC)

After reading it, i'm a bit disappointed at the depth of the article but "intrapersonal communication" is the googable word i was looking for. Joepnl (talk) 03:28, 8 December 2011 (UTC)

Thinking out loud solves problems faster. Kinda like doodling on paper when attempting to sort out your thoughts. This is a neotenous behavior. As children, we talked to ourselves a lot. We gradually lose this behavior as we mature, and it becomes internal dialogue (inner speech or egocentric speech, as opposed to social speech). We still revert to it in stressful situations though. Interestingly enough, the ages when children stop thinking out loud coincides with the ages in which children learn to lie.-- Obsidi♠n Soul 03:46, 8 December 2011 (UTC)

You could equally well ask why we don't do this sort of thing more often. Most of us spend a lot of our time talking silently to ourselves (see internal monologue) -- why do we do it silently rather than aloud? Looie496 (talk) 03:49, 8 December 2011 (UTC)

My mom used to say "People that talk to themselves aloud are either crazy or have money in the bank". Usually just after talking to herself aloud. --Jayron32 04:36, 8 December 2011 (UTC)

I have always known "talking to yourself" as "external processing". Unfortunately, my google trials tonight are not coming up with much by way of references. What I recall is that individuals' "normal" processing mode is somewhere on a continuum from "always talking" to "never talking" about their thoughts. The latter are "internal processors". Most of us have a tendency one way or the other, but may change modes for specific circumstances. (I had a colleague like Kainaw's, but I am much less flexible; I had to keep my door shut whenever she was in her office. I also have a brother-in-law with some of the attributes, though he can be quiet.) Bielle (talk) 05:47, 8 December 2011 (UTC)

Language is a useful tool for critical thinking. Broca's area#Functions says that various simple tasks (such as looking and grasping) activate speech-related brain areas. This doesn't mean that you have to verbalise out loud, but as several people posting above me have implied, holding the words in (and re-processing them internally, rather than letting them go through the full feedback loop, out the mouth and back in through the ears) might be a social nicety and an effort which makes life harder for the thinker.  Card Zero  (talk) 09:27, 8 December 2011 (UTC)

And concerning the 'ouch', exclaiming over something like this actually helps you deal with the pain, especially if you use reserved words for it. Swearing, for example, can be effective at reducing perceived pain, as well as at reducing stress and anger, but only if you don't usually use those words: swearing is only effective if you hardly ever do it, keeping the words taboo. Do we have detail in our article profanity? Apparently not. 86.164.79.174 (talk) 10:11, 8 December 2011 (UTC)

Here's an apt example of what you're describing:[22] ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:23, 8 December 2011 (UTC)

I have some OR on the swearing relieving stress thing. Exactly a year ago just before Christmas I was experiencing severe pain in my jaw, and needed to go to a dentist. Sadly in most cases it is difficult to get help immediately, because of lines, so I was running between different dentists' offices holding my face in my hands. Anyway, winter was at its height, and it was quite cold and snowing, and in course of the running I slipped and fell. And I thought to myself - or I might have even said it out loud - this is too much, I can afford to swear now, I deserve it. I let out a short but satisfying combo of profanity, and it felt good (it felt a bit worse when I realised that a girl walking by had heard it, but I quickly returned to sweet-and-nice mode and politely asked her for the way to the next hospital). Anyway, that one moment, that really helped me relieve the anger at that point. Oh, and for the curious: I had to visit three more dentists' offices before I actually got any help. --Ouro (blah blah) 13:38, 8 December 2011 (UTC)

I believe there's a related phenomenon where some people don't seem to be able to count without saying the numbers out loud. Apparently the speech center is irrevocably linked to the counting part of their brains. StuRat (talk) 18:04, 8 December 2011 (UTC)

Personally, I find myself saying things aloud that have nothing to do with what I am actually thinking about. Common ones when thinking about math problems are "I need money" or random literary quotes. Of course, I can not do it if I really want, or if I'm in public -- it's just what happens when I let my body loose. It's not unusual for wiring to be crisscrossing as you're intensely firing the brain. SamuelRiv (talk) 18:13, 8 December 2011 (UTC)

I suspect that auditory memory could be somehow involved - however easily one might hear words in his imagination, I think actually hearing them has a longer-lasting impact. The specific instance I'm thinking of are some of those puzzle video games where a person is supposed to assign various alien letters to specific positions or a specific order, which I was occasionally called to assist with. ;) My approach is to burn some time at the beginning assigning each alien letter a unique word based on some character it vaguely resembled. Then I would recite the correspondences or the part of the order I knew out loud, and use the audio recording in my mind as a storage medium. Without such tactics, relying on mute recognition of the symbols, I think I would have been hard pressed to solve the puzzles at all. Wnt (talk) 22:23, 8 December 2011 (UTC)

Just for those that are interested, an article from Scientific American on Why the #$%! Do We Swear? For Pain Relief. I remember reading about that a while back. --jjron (talk) 06:32, 9 December 2011 (UTC)

And on a related note, I read recently that asking yourself a question about doing something that you are perhaps trying to avoid (say exercising, e.g., "Am I going to go for a bike ride today?") is more likely to result in you doing it than telling yourself that you have to do it (e.g., "I have to go for a bike ride today"). Unfortunately I can't find the ref at the moment, but the reasoning was something about your brain responding differently to the question than the demand. --jjron (talk) 06:53, 9 December 2011 (UTC)

Proximity of modesto california to san andreas fault

Can anyone tell me how close 1445 Lone Palm Ave, Modesto, California, is to the San Andreas fault? Phil B. Hammond, <email removed> — Preceding unsigned comment added by 174.26.112.130 (talk) 04:08, 8 December 2011 (UTC)

I have removed your email address. No one is going to email you, and publishing your email on a public website assures that you will get bombarded with spam. Modesto, California is in the Central Valley, while the San Andreas Fault runs much closer to the coast, through the Santa Cruz Mountains. It appears to be about 80-90 miles away. The major fault near Modesto is the San Joaquin Fault. --Jayron32 04:32, 8 December 2011 (UTC)

Using this website and this Google Maps tool, I found that the distance to be 62 miles (100 km), probably with an error of ±2 miles (3.2 km) or so. I do not know how accurate the red line is in the website I linked to, but I have no reason to doubt it is off by more than a mile or two. -RunningOnBrains^(talk) 08:34, 8 December 2011 (UTC)

Removing the e-mail but leaving the street address??? So is, that your blue pickup truck out front? ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:17, 8 December 2011 (UTC)

This is, conceptually, more akin to a geological fault-line than any line on a map. Several reputable geological research institutions agree: [1] [2], [3]...

There's no good, precise answer to this - because the San Andreas fault doesn't occur at any one specific place. All the GIS software and precision assisted-GPS can't help you calculate the distance to a fuzzily-defined area.

The thing you have to understand is that there's no "line" that defines the fault. The entire region is what a geologist calls a "fault zone" - a region where large-scale geological structure changes. Any individual rock may fault or slide or schism or crack at at any particular spot; and on the whole, we can sort of "connect the dots" between places that have clear surface-features indicating the continental-scale fault. But that line isn't the fault.

When I used to teach fault mechanics to kindergarteners (as an outreach program from the Geoscience Department), we used the demo of a graham cracker. We would try to break a stack of graham crackers in half, along the "perforated line." What inevitably happens, of course, is a messy, crumbly, crumb-filled mess of loose sediments and uneven fractures in lots of places. This is a better way to think of a fault - it's not at all like a straight line drawn on a map. For the older classes, we used to take the whole group out on field trips to the San Andreas - say, Crystal Springs Reservoir. Every now and then I'd point to something nondescript, contemplate for a while, and say, "the San Andreas fault is ... here." The point is, of course, that large-scale structures are difficult to describe with small-scale measures. It's not unlike the Coastline paradox or the uncertainty principle; but those descriptions require a bit more advanced mathematical thinking, so I only ever tried to convey these more sophisticated idea to the kindergarteners if they seemed bored by graham crackers.

To bring this back to the OP - you should reformulate your idea as, "how close is the Central Valley to the San Andreas fault?" The answer, then, is "about thirty or fifty miles." Any more precise answer is probably false precision. Nimur (talk) 16:32, 8 December 2011 (UTC)

Let me point to this USGS web page, which shows the locations of all of the major faults in California. The Central Valley is pretty much fault-free. Looie496 (talk) 17:02, 8 December 2011 (UTC)

If the question is being asked to build confidence that no earthquake will occur at the given address, it's worth looking at 2011 Christchurch earthquake. This earthquake in an advanced western nation, which killed 181 people and caused maybe $30 billion worth of damage, was one of three in a year there that "occurred on "blind" or unknown faults". Forecasting earthquakes is still a very uncertain science. HiLo48 (talk) 17:40, 8 December 2011 (UTC)

Gallien Kreuger

How do they get such a good bass response from the tiny micro bass combo?--92.28.79.226 (talk) 15:02, 8 December 2011 (UTC)

Mostly by using a well-designed Class-D amplifier and pumping in a lot of power. In this case, the size of the enclosure is not really the limiting factor; it's really all about the quality of the transducer - they use ceramic speakers and neodymium drivers. Have you read their product literature and user manual? Nimur (talk) 16:43, 8 December 2011 (UTC)

Northern/Southern Leaf Blights?

In reading about the Northern and Southern Leaf BLights on Wikipedia, and in googling them, I haven't actually found anything definite on what corn was hybridized with to help prevent/mitigate/reduce the fungus attacks (I already know about crop rotation, and tilling). Any help? Heck froze over (talk) 17:24, 8 December 2011 (UTC)

Lacking any links for it, I can speculate at this point, that the breeders (i.e. the developers) would have selected for varieties that demonstrated resistance to the blight-causing organisms. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:18, 8 December 2011 (UTC)

And now that I've looked at Cochliobolus heterostrophus, it's fairly clear that the article consists entirely of large excerpts from its source reference. In short, it's a copyright violation. The dead giveaway was the reference to something called "T-cms", which was not explained in either place. (Most likely it refers to Cytoplasmic male sterility, which is a trait used in some corn production to avoid the need for detasseling.) ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:25, 8 December 2011 (UTC)

Anything on whether any different plants were used? Heck froze over (talk) 03:46, 9 December 2011 (UTC)

Not sure what you mean. As noted in Blight, there are various types of blights which affect different crops. The corn leaf blight was/is a fungus. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:11, 9 December 2011 (UTC)

Re-reading your original question, asking what corn was "hybridized with", maize is only crossed with maize. What's done is to develop inbred lines which display certain traits, for example resistance to the blight fungus, while at the same time not impacting yield. This is accomplished traditionally through artificial selection. Corn hybrids are produced by crossing inbred lines. If you're asking about genetically modified organisms, i.e. plants whose genes have been altered in the laboratory as opposed to merely trying to isolate traits within the naturally-existing genetics, I don't know the answer to that question, but I can think of different ways it could be done. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:17, 9 December 2011 (UTC)

Blackberry color

I just plunked some blackberries into boiling water with my oatmeal. They then changed color from black to red. My questions:

1) Is this normal ?

2) If so, what happened and did they lose any nutritional value, such a phytochemicals ?

3) If not, is it possible my blackberries were red all along and were just dyed black to trick customers ? StuRat (talk) 17:57, 8 December 2011 (UTC)

All the blackberries I've ever cooked with (and I've been doing it for the thick end of 50 years) have turned red when heat has been applied. I can't say what chemical changes took place, perhaps some scientist can. Honestly, a quick Google search would have found plenty of images of cooked blackberries turning red... --TammyMoet (talk) 18:48, 8 December 2011 (UTC)

[23] suggest blackberries contain soluble anthocyanins that function as an indicator being red in acidic solutions and blue in basic ones. According to that and [24] anthocyanins are one of the primary colour pigments in black berries. However I find it unlikely that blackberries are particularly basic, although I have no idea what pH anthocyanins in blackberries change colour at. It could be ripe blackberries are at a level where the where the pigment appears more blue, so if you are cooking something fairly acidic they will look more red.

But I expect that's not really the answer. It doesn't seem to explain StuRat's case as I presume this was just normal water. The solubility may play a part, if you do find whatever you are cooking them in (e.g. the boiling water in StuRat's case) turning red then likely the anthocyanins are leaching out which will probably make them appear less dark. It could also be a change in the pigments during cooking, degradation, change in the co-pigments etc. As [25] [26] [27] [28] [29] [30] attest, pigment changes in berries can be fairly complicated. (Anthocyanin composition in berries can be fairly complicated too [31].)

A perhaps interesting question is why blackberries which start off as red become 'black' as they grow. These [32] [33] [34] may provide a clue although don't seem to directly say. But my guess is it's an increase in pigment levels (probably anthocyanins although in the last ref about highland blackberries it seems they don't have such high anthocyanin levels so I wonder if Ellagitannins which evidentally are a part of what give wines their colour are a factor there) until the pigments are enough to make them look black ([35] seems to say a similar thing). From reading those results, perhaps in particular Cyanidin 3-glucoside which according to some sources [36] generally gives a dark red/purple colour. These results seem to support my guess that a combination of leaching and perhaps degradation probably play a factor.

Nil Einne (talk) 21:47, 8 December 2011 (UTC)

Thanks. Note that there's oatmeal mixed in with the boiling water, and that might affect pH. I didn't notice much color in the oatmeal, and what was there I attributed to popped cells in the berries. StuRat (talk) 21:55, 8 December 2011 (UTC)

I don't think the oatmeal enters into it. Stewed blackberry and apple is a traditional favourite in the UK (not many folks actually buy them - you just go out and pick them from the brambles which are an annoying weed here). I don't think you even have to cook them, just squashing them yields a red juice. I quote this poem as my reference ;-) Alansplodge (talk) 14:41, 9 December 2011 (UTC)

December 9

Macro communicating with a running plugin in ImageJ

I have written a plugin, that communicates with an IO interface with a programmable logic controller that controls a piece of equipment (a motor that turns the camera, say). I also have written a macro, which repeatedly takes images from a camera, and it runs in a loop such that after every picture it takes, it runs the plugin once.

Now, if I run the macro where every time the camera has to turn it has to run a plugin that repeatedly opens and closes the IO port (in between passing a command telling the motor to move), occasionally there is an error (it is random) that prevents the port from opening, probably due to all the activity. This throws off my experiment however, which has to be calibrated.

What I want to do is run the plugin once (from a macro), keep it and its communications running, and then make calls to the plugin as needed. In the Java plugin I wish to have a run() command which consists of openSerialPort() and a separate turnmotor() command. Can I get the macro to activate the turnmotor() commmand to an already running plugin with an already open port ?

Basically, can a macro run a plugin in the beginning, and then keep making calls to it as needed?

(I ask it here because I assume people at this desk are more familiar with ImageJ). elle _{vécut heureuse} ^{à jamais} (be free) 02:22, 9 December 2011 (UTC)

In Java, you can spawn an external process and send commands to it asynchronously, using the Process API. If you want more specific help, I think you need to elaborate on how your "macro" works - "macro" and "plugin" are both fairly generic terms that could mean a lot of different things. Can you name or explain the specific tools that you're working with? (I'm guessing that you mean ImageJ plugin and ImageJ macros, can you confirm?)

In the more general sense, you're running in to a problem because you're relying on open loop control. That is - if anything happens in your setup that you don't expect, (such as a random error that causes one instance of a loop to fail), you have no feedback to convey this back to your software controller. As a result, the system is in an uncalibrated state. You might want to fix that problem, by adding a feedback (that is, by adding a sensor, and verifying the value is what you expected it should be). Nimur (talk) 03:18, 9 December 2011 (UTC)

Quality of soy protein

Soy protein contains Trypsin inhibitor. I have heard it is necessary to heat soy chunks to inactivate the inhibitor. I want to know at exactly what temperature the inhibitor is destroyed? Also, is there any reliable data available on the amino acid content of soy protein? --Foyrutu (talk) 05:07, 9 December 2011 (UTC)

The protein quality of soy protein is quite good. The PDCAAS of isolated soy protein is 0.92 (the same as beef), and the Biological Value of whole soybeans is 96 (better than beef). See Soy protein#Nutrition. Red Act (talk) 06:04, 9 December 2011 (UTC)

Thanks. Can you please provide some info about the trypsin inhibitor? --Foyrutu (talk) 06:25, 9 December 2011 (UTC)

"Destroyed" is the wrong word in my opinion. Serine protease inhibitors are a class of globular proteins that inhibit other globular proteins (enzymes), heating denatures (or unfolds) them. This results in a loss of activity but doesn't literally break the polypeptide chain into its core substituents, thus "broken" would be more appropriate than "destroyed". (+)H₃N-Protein\Chemist-CO₂(-) 17:56, 9 December 2011 (UTC)

Sort of a Science history question

Since the arrival of quantum mechanics, has there been any progress in the classic mechanics that would happen anyway without quantum mechanics?I mean has classical mechanics grown independently from quantum mechanics since then?--Irrational number (talk) 10:23, 9 December 2011 (UTC)

Certainly. Take the Kolmogorov–Arnold–Moser theorem as an example. --Wrongfilter (talk) 11:36, 9 December 2011 (UTC)

Fluid mechanics in particular is a field that has seen a lot of progress in the last century - partly due to breakthroughs in computing - most of which is completely independent of quantum mechanics. (Technically, I suppose the supercomputers used might not exist without enough quantum mechanics to understand semiconductors, but that's outside the scope of the question, I suppose) Smurrayinchester 13:15, 9 December 2011 (UTC)

Entirely new fields of classic mechanics such as chaos have been developed after the advent of Quantum mechanics. Dauto (talk) 14:50, 9 December 2011 (UTC)

Is chaos theory entirely unrelated to quantum mechanics ? StuRat (talk) 19:46, 9 December 2011 (UTC)

Does heating milk affect calcium and vitamin D content?

Thanks. Imagine Reason (talk) 10:38, 9 December 2011 (UTC)

Being an element, the calcium will still be there after heating, possibly in greater concentration due to water evaporation. The Vitamin D is another matter. I believe that compound would be broken down to some extent by heat. HiLo48 (talk) 11:00, 9 December 2011 (UTC)

I haven't spotted a really high-quality source, but the literature I've found says that vitamin D is quite robust against heating. Pasteurization does not cause any significant breakdown, although heating of the purified vitamin to oven temperatures well above boiling does. Looie496 (talk) 17:51, 9 December 2011 (UTC)

Note that while calcium will still be present, it may not be as bio-available if the vitamin D is destroyed, since D is needed to absorb calcium. StuRat (talk) 19:39, 9 December 2011 (UTC)

Fusion power

When will fusion power be practical? --108.225.117.205 (talk) 15:52, 9 December 2011 (UTC)

When sustained containment is achieved using significantly less energy than the reaction provides. Roger (talk) 16:00, 9 December 2011 (UTC)

Well, that will depend on who you ask, what you mean by 'fusion power', and what you mean by practical. If you are sufficiently wealthy and gullible, you can buy yourself a 'fusion powered' magic teapot right now. If, on the other hand, you'd rather not involve yourself with such dubious enterprises, you are obviously going to have to wait until someone works out the technology to do this - and given the length of time this has already been worked on, without useful results as far as actually producing a useful power source, I'd not expect anything in the short term, so any answer would necessarily be speculative. Of course, most of our energy needs are already met by a fusion-powered generator - but I'd assume that isn't what you mean. AndyTheGrump (talk) 16:03, 9 December 2011 (UTC)

It's almost become an in-joke that fusion power is always "30 years away". ITER is about ten years from going live, but even if it succeeds, ITER is a a test-bed system that won't produce power at a commercial level. The sketch for an initial commercial fusion powerplant is DEMO which gives a (handwavey) date of 2033; but given that ITER is a decade behind schedule, that could put DEMO at about, ahem, 30 years away. -- Finlay McWalterჷTalk 16:04, 9 December 2011 (UTC)

The reference desk can't speculate about future events. For information about national energy policy in the United States, you might read the informative website from the Energy Information Agency, at http://eia.doe.gov. Nuclear fusion is possible, and significant research is still ongoing, but fusion power-plants are definitely not part of the national energy road-map for the foreseeable future - that is, as far as the DOE plans are publicized. You might like this "retro" take on the future of fusion, [37] and this article, Harnessing the Energy of the Stars. As far as research, the DOE just boosted the funding for the National Ignition Facility. Nimur (talk) 16:04, 9 December 2011 (UTC)

It probably should be noted that DOE's interest in NIF is not based on its possibility for electricity generation (which is fairly remote), but for its weapons-research applications (it helps you simulate H-bombs, which is good in an era where you can't test nuclear weapons). --Mr.98 (talk) 17:37, 9 December 2011 (UTC)

There are a few major milestones that need to be reached:

• Scientific breakeven. This is when we actually get more energy out of controlled thermonuclear reactions than we require to get them started. We haven't hit that stage yet. NIF should hit it in the next couple of years. ITER might hit it in the next decade.
• Electric breakeven. This is means you actually generate net electricity at your reactor in question. (You can achieve scientific breakeven — getting more energy out of the reactions than you put into them — without getting electric breakeven, because scientific breakeven ignores a lot of other electrical outputs.)
• Economic breakeven. This is when you've gotten a system worked out where the costs of generating electrical power out of controlled fusion reactions are in some way comparable to the costs of generating other forms of electricity. You can artificially manipulate this, if you are a state, by taxing other forms of energy, but there are limits to practicality (and what people will pay for).

I've only attached a date prediction to the first one. This seems reasonably likely. But the other ones, who knows. It depends on the methods, it depends on what problems and inefficiencies are encountered. For a viable ICF plant, for example, you not only have to have lasers that can make the fusion reactions, but you have to have a system that allows you to produce cheap and reliable pellets, and to pump them through the entire system at a rate that can sustain large electrical output (most ICF plants envision blasting several pellets per minute, if not dozens per minute). I know less about the practical requirements for MCF plants but they no doubt have them as well. All of these are separate and potentially even more difficult problems than just hitting scientific breakeven (which ought to be achievable just by scaling things up, which is what NIF and ITER are about), and even scientific breakeven has been unattained after six decades of research.

I think it would be wildly improbable for actual fusion plants to be on the market for the next 40 years. It could be longer than that. It might not ever occur. There are huge engineering uncertainties, and experience in the field has led most thoughtful people (whose budgets don't depend on fusion hype) to be pretty wary about optimistic predictions. --Mr.98 (talk) 17:37, 9 December 2011 (UTC)

How would the 8 rotor Enigma machine have changed WWII?

A little while ago I was reading up on the Enigma machine, how it was made, used and decrypted. Through one of the articles I read, there was mention of an 8 rotor Enigma machine that was ultimately abandoned in favor of the 3 and 4 rotor versions due to the mechanisms' repeated tendency to jam. My question is as follows. If the germans had poured the resources needed to, and managed to bring the 8 rotor Enigma to the reliability levels of the 3 and 4 rotor versions, then deployed it instead of the 3 and 4 rotor versions wherever feasible (on ships, subs, HQ's, and so on), could the allies still have managed to break it as completely as they did the 3 and 4 rotor versions, or even to some partial extent? How would this one fact have affected the allied intelligence gathering effort and ultimately the course of the war? Also, mathematically speaking, how much harder would this have made any effort to decrypt the Enigma machine (both with the technology of the time and with today's modern technology)? Would any of the short-cuts used at the time have still worked, and would it be possible to brute force it with today's technology in any useful time frame? — Preceding unsigned comment added by 79.116.6.234 (talk) 17:45, 9 December 2011 (UTC)

Our article on the cryptanalysis of the Enigma is instructive. In particular, we note that "good operating procedures, properly enforced, would have made the cipher unbreakable". Thus, the mechanical characteristics of the device weren't the primary reason that the Allies were able to break the encryption. Would additional rotors have improved security? Probably -- at minimum, it would have exponentially lengthened brute-force attempts at codebreaking. However, fundamental misuse all but certainly would have continued (if anything, increased mechanical complexity could have led to even less secure operational practice due to laziness). — Lomn 19:12, 9 December 2011 (UTC)

An anecdote to explain how the laziness helped... When the Germans first jumped from the 3 rotor to the 4 and 5 rotor Enigmas, the Polish had enough information to make their own 3 rotor Enigma copies. Since the manuals for the Germans covered the 3 rotor system, many people only used 3 of the rotors. With that help, the Polish were able to crack the messages and work out the details of the two new rotors so they could be used in new Polish Enigma copies. I wonder how much of that is in the article. I have a few history of code breaking books and I can add references if it is missing. -- kainaw™ 19:16, 9 December 2011 (UTC)

I realize that german laziness was the prime factor that helped the allies break the Enigma machine, but my question wasn't about the standard Enigma machines that used 3 or 4 rotors at a time (out of a maximum of 8 rotors supplied). My question was about what if they kept improving on the Enigma H (model H29, the last of the printer Enigmas), and deployed a more portable and reliable version of it? Could it have helped them in any way despite the operator laziness and misuse? — Preceding unsigned comment added by 79.116.6.234 (talk) 19:31, 9 December 2011 (UTC)

The Lorenz geheimschieber had 12 rotors, and was broken. Sure, more rotors helps, but just as with modern ciphers and their key lengths, no amount of added search space will save an operator from his mistakes (and bigger spaces tend to fool people into thinking they've made an uncrackable system, which leads to overconfidence). 91.125.17.58 (talk) 19:37, 9 December 2011 (UTC)

Full moon

How can we see a full moon if it happens when the earth is between the moon and the sun? Wouldn't the earth block the sun's light from reaching the moon? 74.15.136.30 (talk) 18:49, 9 December 2011 (UTC)

Most of the time, moon, earth and sun are not exactly on a line, so the moon passes above or below earth's shadow. Every now and then, the moon passes through the shadow, and then we get a lunar eclipse. The next one is: tomorrow. --Wrongfilter (talk) 18:56, 9 December 2011 (UTC)

That's exactly what happens during a lunar eclipse, but as you've no doubt noticed, we don't have one of those (or a solar eclipse) every month. The orbit of the moon happens to be inclined about 5 degrees relative to the ecliptic (the plane defined by the Earth's orbit about the sun), and so most months the moon is either above or below the direct sun-Earth path, resulting in a full moon with no eclipse. — Lomn 18:58, 9 December 2011 (UTC)

And the relatively tiny sizes of the Earth and Moon compared with the distance between them (or put another way, the tiny ratio between the size of the Earth's shadow and the circumference of the Moon's orbit) means that, even if their planes were perfectly aligned, you'd only get a total eclipse of about 2 hrs a month, punctuating the middle of the 2 or 3 days you'd call the moon apparently "full" to the naked eye. 91.125.17.58 (talk) 19:44, 9 December 2011 (UTC)

You are correct, that it's not quite a full moon. However, a 99.9% full moon is indistinguishable from a 100% full moon, when viewed by the naked eye. StuRat (talk) 19:28, 9 December 2011 (UTC)

Synthetic honey

Considering the laboriousness and expense of apiculture, and the instability of bee populations, it seems like there would be a strong economic case for "cutting out the bee". Honey is mostly a mixture of water and fructose, glucose, maltose, and sucrose in particular proportions, with trace amounts of other minerals. Could this mixture not be approximated by some industrial process using vegetable-derived sugars and artificial flavorings? Even if the product were greatly inferior, there would probably be a market for it, just as there is a market for horrible fake maple syrup. So why have I never seen synthetic honey for sale? LANTZY^TALK 22:39, 9 December 2011 (UTC)

I've seen fake honey for sale. It usually has a tiny bit of honey in it and the rest is corn syrup, etc. StuRat (talk) 22:46, 9 December 2011 (UTC)

If you ignore the water content in both (17% of honey and 21% of HFCS, by my very undependable memory, the fructose-glucose ratio of the two are very similar. I doubt many people will notice the other sugars in honey. Imagine Reason (talk) 23:55, 9 December 2011 (UTC)

Does maltose have a distinctive taste? LANTZY^TALK 23:57, 9 December 2011 (UTC)