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December 7

Relating to heat transfer

Why heat transfers from hot body to cold body without any work positive or negative while the reverse is explained by second law of thermodynamics.150.242.150.130 (talk) 07:37, 7 December 2015 (UTC)

You can get a lot of energy from your first example, that's how engines work. See Carnot Cycle for a no doubt convoluted and innaccurate explanation. Note that the carnot efficiency defines the maximum useful work you can get from a given transaction between a hot and cold reservoir, practical designs will always get less, or quite often, none at all.Greglocock (talk) 09:41, 7 December 2015 (UTC)

The second law of thermodynamics says a process will occur, without work being done by the surroundings, if entropy increases or remains constant. The flow of heat from a hot body to a cold body causes entropy to increase, and so the flow of heat in this direction occurs spontaneously. Dolphin (t) 10:01, 7 December 2015 (UTC)

Think about temperature as being a measure of the speed of motion of atoms - that's pretty much the classical definition. If you imagine a container of fast-moving things (think ping-pong balls bouncing around in a room at high speed) - then imagine opening a door to a room full of very slow moving things. At the atomic level, this is a picture of a hot object being brought into contact with a cold one. You can imagine a fast moving ball going through the door and hitting a slower moving one - resulting in the fast one going a bit slower and the slow one going a bit faster. This happens a lot, so on average, the fast-moving balls wind up going slower, and the slow moving balls go faster - keep this going for long enough and sooner or later, all of the balls are going at the same speed. Heat moved from the hotter object to the colder one - and continued to do so until the temperatures are equal.

For the reverse to be the case, you'd somehow need a slow-moving ball to hit a fast moving one - and as a result, for the slower one to go even slower and the faster one even faster - but that seems very counter-intuitive. You wouldn't expect the fast balls to end up going yet faster and the slow ones to go even slower...and indeed heat doesn't flow from cold objects into hotter ones. SteveBaker (talk) 15:28, 7 December 2015 (UTC)

The analogy is very helpful and understandable on intuitive level.Will →you please elaborately explain by second law and is the word 'spontaneously' in this context( second law) implying no work??.Books on heat/ thermodynamics leave this as self evident.150.242.150.164 (talk) 17:01, 7 December 2015 (UTC) Thanks Dolphin and Steve.150.242.150.164 (talk) 17:04, 7 December 2015 (UTC)

No, I don't believe spontaneously means "no work", I believe it means THAT IS "the work". If you delve much deeper than that, you might reach the Problem of induction. Vespine (talk) 02:41, 8 December 2015 (UTC)

Anyone recognise this insect ?

Unknown insect

— Preceding unsigned comment added by Bobatnet (talk • contribs) 08:36, 7 December 2015 (UTC)

There are many thousands of varieties of caterpillar, and many hundreds with eye spots. Can you tell us where it was seen?--Shantavira|^{feed me} 09:54, 7 December 2015 (UTC)

Saw this in Chandigarh, India on the street with greenery around. Bobatnet (talk) 11:04, 7 December 2015 (UTC)

It looks like the caterpillar of the Oleander Hawk-moth - Daphnis nerii — Preceding unsigned comment added by 86.140.37.142 (talk) 12:46, 7 December 2015 (UTC)

Our article: Daphnis nerii. -- ToE 15:59, 7 December 2015 (UTC)

Looks just like a draught excluder to me.Artjo (talk) 21:44, 7 December 2015 (UTC)

Don't go calling my girlfriend a "draught excluder" Myles325a (talk) 04:10, 9 December 2015 (UTC)

Trade secrets and labs

If anyone with enough money can order a chemical laboratory analysis of, say, a Coca-Cola sample, the Coca-Cola formula and similar products wouldn't be trade secrets anymore, would they? (provided that the results are published in open access)--93.174.25.12 (talk) 10:51, 7 December 2015 (UTC)

It is possible that the laws defining trade secrets would forbid such activity. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:27, 7 December 2015 (UTC)

• This is an example of reverse engineering (that article also explains the legal issues that can arise). In general, no laws protect trade secrets - if they were protected, there'd be no point getting a patent (the basic idea of a patent is to encourage companies to reveal their secrets in exchange for legal protection). It is possible to reverse engineer foodstuffs; William Poundstone, for example, tested the KFC Original Recipe and found that the "11 secret herbs and spices" are salt, monosodium glutamate and black pepper (although for something like Coca-Cola that contains around a dozen flavouring oils the process of separating them would be long and time consuming). I'd imagine that Pepsi knows exactly what's in Coca-Cola (and vice versa), but there's less value than you think in producing a drink that tastes like Coca-Cola. You probably can't be much cheaper than Coca-Cola (they can charge a premium for the brand, but they also have huge economies of scale – Coca-Cola seems to control a huge chunk of the world's vanilla market, for example, while you would have to go through wholesalers) and you certainly can't have better marketing than Coca-Cola. According to Cola Wars, RC Cola tastes identical to Pepsi Cola, but RC Cola remains a tiny player in the contest because it doesn't have Pepsi's massive multinational backing. Smurrayinchester 14:28, 7 December 2015 (UTC)

Huh? The Cola Wars article does not say that Pepsi and RC taste the same. Nor would most people, I think. Also while Poundstone may have claimed that he reverse engineered KFC spices that is no proof that he did so correctly. Flavor profiles are quite complex. Rmhermen (talk) 22:55, 7 December 2015 (UTC)

I think Smurrayinchester is thinking of the Pepsi Challenge article, which does make the claim with a ref from 1950. I haven't check the ref and in any case even if it were true in 1950 it may not be now. But one thing to remember is that even if most people can't taste the difference between two products, if there are certain people who are consistently able to tell the difference (even correctly identify two different batches of one and two different batches of the other), this implies that there likely is a difference. A lot of research tends to focus on whether most people are able to tell the difference, which is interesting for numerous reasons, but is actually a lot less useful in trying to determine if there really is a perceptual difference. (Sometimes research looks in to those who are convinced they can tell the difference, but again it doesn't always explore those who appear to have succeeded that well.)

Loosely related but [1] is interesting. It suggests, perhaps not surprisingly that many of those tested were able to taste the difference between US and Mexican coke (how much of this is due to the sweetner difference and how much is due to other compositional differences, who knows). And that most of those (they are Americans so probably used to American coke) prefered the taste of American coke, but that some people preferred coke they were told was Mexican coke. There was also a preference for glasses bottles by some. (Although the tests probably aren't that well designed for scientific purposes.)

Nil Einne (talk) 02:18, 8 December 2015 (UTC)

• At least the 1983 version of Original Recipe was those ingredients, the same article you cite notes that a year earlier, Harland Sanders himself noted that this was not his orginal recipe, and even recommended an alternate source for the correct spice blend instead of the KFC corporate blend. And now that 22 years have past, I'm not sure how accurate Poundstones results would be for today's KFC recipe. Just noting that Poundstone's test was not a) on Harland Sanders actual recipe (the one held in the vault with the 11 vials of the actual spices to be used) or b) guaranteed to still be the recipe used today. --Jayron32 16:11, 7 December 2015 (UTC)

I'm with Rmhermen here, I wouldn't even be confident Poundstone results were true for the 1983 version of the official corporate blend. I'm sure he genuinely believed it was true, but it doesn't mean he was right. Even nowadays, I would be cautious about any labratory analysis, let alone a 1983 one. I'm not saying it's impossible but it's easy to screw up. Although at least Poundstone was (if I understand our article correctly), testing the uncooked mix rather than the coating from the chicken. Of course, even if Poundstone results were true for the 1983 corporate version it may be only the US version. KFC already had a resonable international presence in 1983 and I suspect some of these were large enough that the mix was produced locally.

Definitely in modern times, most people who claim to have replicated the current recipe use more ingredients. Of course people can be fairly bad at re-producing stuff based on taste tests. Compare for example many of the McDonald's special sauce recipes to that reveal by McDonald's in Canada or the ingredient lists some publish. Although it's possible some of these were based on local versions of the special sauce which were different. And you also get people convinced that the special sauce sold in packets or bottles in Australia, NZ etc is different from which comes on the burgers (well perhaps because of batch difference etc it is, but the bottles/packages are unlikely to be universal bad as many of these people are convinced is the case unless perhaps it's "contamination" from the meat, lettuce etc that they like.).

Nil Einne (talk) 01:43, 8 December 2015 (UTC)

"No laws protect trade secrets" is not entirely true. There are laws on the books specifically to protect trade secrets (U.S.C. §§1831-1839) - but these are mainly aimed at those obtaining the secret by fraudulent means. That is, it's against the law (over and above things like standard breach of NDAs and breaking-and-entering charges) for an employee at Coca-Cola who has access to the recipe to leak that recipe to someone else, or for someone to break into Coca-Cola's headquarters and steal the recipe. In 2006 there was actually a case about this, where three people were accused of stealing Coke's formula and trying to sell it to Pepsi - Pepsi was actually the one who turned them in [2]. However, as you mention, there's really no such prohibition on reverse engineering the secret formula from legally-obtained sources. In fact, there's a somewhat convincing argument that the original recipe for Coca-Cola is already out there in a publicly available form [3] [4] - though not necessarily with the tweaks needed for modern ingredient differences. -- 160.129.138.186 (talk) 16:26, 7 December 2015 (UTC)

I think your first link is broken; you probably meant to say "18 USC §§1831-1839", also known as 18 USC Chapter 90, PROTECTION OF TRADE SECRETS. It is available online at no cost from the United States GPO, or from the United States House of Representatives webpage; and it is also re-hosted in an unofficial form by the Cornell Legal Information Institute at this corrected URL.

Surely there are also many additional state and Federal regulations that pertain to trade secrets.

Nimur (talk) 01:24, 8 December 2015 (UTC)

My understanding is that there are a number of state laws, but little of much effect on a federal level, though a new federal law is in the pipeline. Though I'm not that knowledgeable on US law, and only know this because of articles on a blog I follow for professional reasons e.g. . MChesterMC (talk) 09:16, 8 December 2015 (UTC)

Here's an excerpt from The United States Attorney's Criminal Resource Manual, on 18 U.S.C. § 1831. (Corresponding manuals exist for each of the other sections). This publication aims to help Government prosecutors understand procedures for successfully trying federal crimes. For example, in section 3, there are many precedent cases listed and analyzed for review. I would posit that a law authorizing a 15-year term in Federal prison, that has been successfully tried and yielded previous convictions, is an example of a law with a "significant" effect. Nimur (talk) 15:48, 8 December 2015 (UTC)

And, here is a state law for California: the Uniform Trade Secrets Act, my state's incarnation of the recommendations put forth as the Uniform Trade Secrets Act proposal. Most states have similar laws. Our article lists several precedent cases tried as violations of state law, or brought as civil suits. Nimur (talk) 16:23, 8 December 2015 (UTC)

I'm skeptical there's such a thing as law. If you annoy a major corporation, you're going to lose everything you have in lawsuits. It's just a matter of naked power (possibly opposed by "terrorism"). McLibel kind of stuff. It seems like even in much simpler analyses, like finding human DNA in hot dogs, those making them don't dare say things that don't sound nice. Wnt (talk) 16:34, 9 December 2015 (UTC)

Yes, trade secrets are an interesting aspect of intellectual property law, but when it comes to the "secret formulas" of brand-name foods like Coca-Cola and Kentucky Fried Chicken, it's actually a different game (and maybe even a little more interesting).

In the case of Coke and KFC, their "secret formulas" are more than the particular recipes for certain ingredients in certain ratios. Much more important is the mythos that those two companies have quite successfully built up around their formulas, and that mythos is, at this point, pretty much untouchable. Importantly, a key part of the mythos is not just that the formula tastes good, it's that it is secret, that no one can know what it is.

Suppose I managed to figure out the exact formula for Coca-Cola. (Doesn't manage how I did it, but do suppose that it's exact, down to as many decimal places as in whatever master copy the Coca-Cola Corporation has stashed away in whatever uber-secure vault they've hypothetically got for theirs.) Quite aside from anything which trade secret or any other IP law might say, if I go public with my formula, Coca-Cola will simply say, "No, that is not the official formula". Now, you might say they're lying, but you can never prove it, because they will never ever show you their copy of the formula. And, in an important sense, my formula is indeed not official, and if I made some and put it in a bottle, it would never be The Real Thing®. (And if you ran a non-blind taste test, I'm reasonably sure you'd get the statistically significant result that the non-official formula indeed did not taste the same.) —Steve Summit (talk) 16:30, 9 December 2015 (UTC)

Civil engineering

Is civil engineering a mature field with not much scope for advances in research compared to biology or medicine? — Preceding unsigned comment added by 2A02:C7D:B901:CC00:6591:E3B9:275A:A9A4 (talk) 15:29, 7 December 2015 (UTC)

Read this. --Jayron32 16:07, 7 December 2015 (UTC)

Civil engineering along with any other engineering field, specialize in problem solving and thereofre ay enginnering field tends to keep its scope into it respected field to be able to solve problems as they appear. The field itslef is very mature and has room to grow from and advance through the form of bridges, roads, and many more. Little fact, civil engineers save more people every yea then doctors. This may not seem right but everytime you drive over a bridge you are putting your life into the hands of the civil engineer that apporved the contrution of that bridge and made it possible.

cleaning the dye off money

so they started putting that coloured dye in with the money you get from security vans or out of a cash machine, how does it work and how do you clean it off the money and off your hands? Hugo Baptiste (talk) 19:10, 7 December 2015 (UTC)

Just robbed a bank, did you ? :-) StuRat (talk) 19:13, 7 December 2015 (UTC)

See Dye pack for our article. See a lawyer if you _have_ robbed a bank. Tevildo (talk) 19:34, 7 December 2015 (UTC)

You could try returning your ill-gotten gains, and say your older brother made you do it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:46, 7 December 2015 (UTC)

Seriously, in the US, the Treasury Department will replace damaged currency if enough is left of it to prove how much there was. As a volunteer for a disaster recovery charity, this is something I've mentioned to one or two affected families. Jc3s5h (talk) 00:38, 8 December 2015 (UTC)

The police will do this for you for free. Just bring yourself and the money to the police station, it is a free service. 175.45.116.66 (talk) 22:28, 7 December 2015 (UTC)

There's no need to clean the money, all the banks need to do is show that the dyed mess really is a certain amount of money and it will be destroyed and replaced with nice new notes. Any dye will wear off skin eventually without anything being done even if only by shedding skin cells, I'm sure a bit of rubbing and washing would reduce any marks considerably. Dmcq (talk) 00:08, 8 December 2015 (UTC)

• The most common dye used is Disperse Red 9, which is apparently "slightly soluble in benzene and carbon tetrachloride" – but these are both pretty toxic chemicals (and I wouldn't be surprised if they also wrecked the actual printing on the notes). Brings a whole new meaning to the phrase money laundering. Smurrayinchester 15:00, 8 December 2015 (UTC)

December 8

From Computer Science to Civil Engineering?

How difficult would it be for someone out of school for a decade to get a Masters in civil engineering with a Computer Science background? What kind of CE undergraduate work would be necessary? 69.22.242.15 (talk) 17:08, 8 December 2015 (UTC)

How difficult will depend on how hard you want to work on courses, and what your finances are (e.g. how much you'll have to work for paying jobs, will you be able to attend at all if no funding package is offered). You should contact programs directly to ask about course requirements. Typically some undergrad courses can be picked up whilst completing the masters course work, though that may add time to completion time for the degree. See here [5] e.g. for what U. Illinois needs to see to review your application. My guess is that with strong records in CS you'll be able to be admitted to good programs, especially if you did general engineering coursework (i.e. your CS degree is considered an engineering degree, and you already have proper credits in math and basic science). But your best bet for good info will be to contact degree programs directly. SemanticMantis (talk) 17:34, 8 December 2015 (UTC)

Per SemanticMantis, you need to contact someone in the advising department of the school you intend to go to; usually there is someone within (in this case) the Civil Engineering department who will lay out what is necessary to get the degree you want. --Jayron32 17:43, 8 December 2015 (UTC)

Thiourea Reactions

I was curious if it's possible to make thiourea from ammonia and thiocyanate. I know that thiourea is often made from ammonium thiocyanate, which is a combination of ammonia and thiocyanate, right? I didn't know, since ammonium thiocyanate is usually produced with carbon disulfide and ammonia. However, thiocyanate is chemically similar to carbon disulfide. I was also wondering if there was any way to make thiourea from urea. The two are so similar, but I don't know how you could remove that oxygen atom and replace it with sulfur.174.131.61.0 (talk) 18:17, 8 December 2015 (UTC)

Ammonia (NH3) is not the same as ammonium (NH4+). 82.8.32.177 (talk) 22:16, 8 December 2015 (UTC)

The method to make it, is to fuse ammonium thiocyanate at temperatures close to but below 182°C. It melts at 148°C, but conversion is very slow at this temperature. The two substances are in equilibrium in the melt. Thiourea makes up about 24% at 170°. Thiocyanate is not a substance in itself, it is an anion, and you would have it in the form of a salt, such as potassium thiocyanate. Heating a gas with a solid salt will not get you very far as the ammonium will be at low concentration. If you heat ammonium thiocyanate too hot you get an irreverable conversion to guanidine thiocyanate and ammonium trithiocarbonate. So use your ammonia and thiocyanate salt first to make ammonium thiocyanate. Graeme Bartlett (talk) 10:58, 9 December 2015 (UTC)

December 9

Eroded teeth

Do teeth which have been eroded by plaque grow back if maintained well and by taking calcium supplements ? — Preceding unsigned comment added by 175.101.24.136 (talk) 08:36, 9 December 2015 (UTC)

No. This is not medical advice, merely a statement of the bleeding obvious. Greglocock (talk) 10:33, 9 December 2015 (UTC)

Not now, but maybe someday soon. --Jayron32 16:07, 9 December 2015 (UTC)

Read tooth enamel. Enamel is non-living, so it can't rebuild itself. However, limited demineralization of enamel can be reversed if the local pH stays high enough; fluoride accelerates this, which is why it's in toothpaste and other dental care items. Dental caries is suggested reading as well. --71.119.131.184 (talk) 22:30, 9 December 2015 (UTC)

TianQin planned gravitational wave detector

In a recent blog entry V. T. Toth writes that he is in Guangzhou "on account of a conference about a planned space-borne gravitational wave detector called TianQin." This statement is probably accurate because Toth is a physicist who does astrophysics. Do we have an article about this particular gravitational wave detector? Is it the same as any of the ones mentioned in Gravitational-wave observatory #Specific_operational_and_planned_gravitational-wave_detectors? – b_jonas 11:51, 9 December 2015 (UTC)

I don't think we have an article. There is not much written on it yet. see http://arxiv.org/abs/1512.02076 and http://arxiv.org/abs/1510.04754. Graeme Bartlett (talk) 12:25, 9 December 2015 (UTC)

Even on Chinese Wikipedia 天琴 is a redirect to the article for the constellation Lyra. Graeme Bartlett (talk) 12:29, 9 December 2015 (UTC)

Thank you for the answer and the links. – b_jonas 17:02, 9 December 2015 (UTC)

Cool, Graeme! How did you find out the correct characters? For all I know, it could have been 天禽 or even 甜芹. ;-) — Sebastian 19:35, 9 December 2015 (UTC)

The footnote says "In Chinese, TianQin means a musical instrument, namely a zither, in space. The TianQin experiment is metaphorically seen as a zither that is being played by the Nature itself through gravitational waves". It can't be that hard to work out the correct characters, even if you don't understand Mandarin. Nil Einne (talk) 20:04, 9 December 2015 (UTC)

How I knew the characters, is that the http://www.seminar.net.cn/ link has Chinese and equivalent English text on it. Google translate confirms those two characters have that sound. Also 天 is a clue, meaning sky / heaven. Graeme Bartlett (talk) 20:54, 9 December 2015 (UTC)

Thanks, guys. Of course, if I had seen the footnote, I would have reached that same conclusion. My question wasn't meant to express doubt, as the two characters make complete sense and their Pinyin transcription matches. Rather, I just wanted learn from Graeme. — Sebastian 23:46, 10 December 2015 (UTC)

During prehistoric times, what was the likelihood of growing up to maturity and reproducing for humans?

During prehistoric times, what was the likelihood of growing up to maturity and reproducing for humans? How often did females become pregnant during their lifetimes? How high was the infant mortality? How many individuals of a typical population would survive into adulthood and reproduce? 66.213.29.17 (talk) 19:09, 9 December 2015 (UTC)

It's difficult to give a meaningful answer to your questions because nobody was sufficiently developed enough to collect, collate and publish statistics at the time. We can only guess. --TammyMoet (talk) 21:28, 9 December 2015 (UTC)

We have an article om Life expectancy which gives our current best estimates over history back to paleolithic times. Vespine (talk) 21:44, 9 December 2015 (UTC)

It's true we don't have statistics from prehistory, but that doesn't mean we're just making wild guesses. We can make informed estimates from archaeological evidence. --71.119.131.184 (talk) 22:33, 9 December 2015 (UTC)

Do you know what the word prehistoric means? Let me give you a hint. Before any numeric or linguistic recordings were made. 175.45.116.66 (talk) 02:47, 10 December 2015 (UTC)

That's rather harsh, 175. I don't know with what accuracy the answer to this question is known, but it is precisely the sort of thing that physical anthropologists try to figure out. -- ToE 04:06, 10 December 2015 (UTC)

Just starting with the stats of those humans who still live in prehistoric times, it's possible to start guessing some ballpark numbers. We are not completely at dark here. --Denidi (talk) 18:48, 10 December 2015 (UTC)

Bit off topic, but a lot of our knowledge and what we call "established science" is based on indirect evidence. It's nothing unusual. From the chemical composition of the sun to the speed of light in a vacuum, science doesn't really work with "certainties" much (if at all once you get deep enough) All we ever really do is "only guess", but it hasn't stopped science from being the most successful method of obtaining knowledge which is, at the very least useful, even if we don't accept it's "True" for certain. Vespine (talk) 00:01, 11 December 2015 (UTC)

December 10

Americans and the metric system

How come many people in the USA seems to be so opposed to using the metric system? — Preceding unsigned comment added by 2A00:801:210:54F6:8093:E0B9:4DBE:31C7 (talk) 06:46, 10 December 2015 (UTC)

Maybe because Americans are able to remember a handful of trivial conversion factors, and multiply by numbers other than 10? --Trovatore (talk) 03:20, 11 December 2015 (UTC)

Trivial? Do you easily know how many gallons of water you can fit in 130 cubic feet? I know how many liters of water I can fit in 13 cubic meters without using any time or device at all. --Lgriot (talk) 13:09, 11 December 2015 (UTC)

A cubic foot is about 7 gallons; I know that off the top of my head, so 900, give or take. What's the problem? --Trovatore (talk) 18:50, 11 December 2015 (UTC)

The problem is that you are 7.45% wrong. --Lgriot (talk) 19:00, 11 December 2015 (UTC)

So what? If I need an answer better than that, I won't do it in my head. Mental arithmetic is for quick estimation; it doesn't have to be precise. If you need a precise answer you pull out a calculator. --Trovatore (talk) 19:05, 11 December 2015 (UTC)

Familiarity and inertia. This explains why the US is comfortable with power stations rated in MW, light bulbs in watts, computer speeds in metric multiples of Hz, and athletes competing in the 100m, 200 m, 1500 m etc. Widneymanor (talk) 09:21, 10 December 2015 (UTC)

Wikipedia has an interesting article on Metrication in the United States.--Shantavira|^{feed me} 09:35, 10 December 2015 (UTC)

• The United States tends to be slow adopting international standards of various kinds (it's also one of the few places that doesn't use ISO 216 paper size, which makes printing US documents endlessly annoying) for a couple of reasons. The public never likes changes, especially when they're perceived as foreign (Metrication in the United Kingdom has the same problem – populist politicians are good at spinning this sort of thing as a "foreign invasion"), and being relatively isolated (it only has two land neighbours) with a large internal economy, it can ignore what other countries do in a way that a state in, say, Central Europe with half-a-dozen neighbours can't. The biggest benefit of adopting the metric system would arguably be trade with other metric countries, and the US gets around that with dual labelling. (For another example of this neighbor effect, see Right- and left-hand traffic. The big continents are dominated by right-hand drive (except for roads in southern Africa and the Indian subcontinent, which are largely isolated from the larger networks) because being an outlier causes so many problems that the public and financial upheaval was worth it, but many islands remain left-hand drive because there's little benefit to changing.) Or as Grampa Simpson once said: "The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it!" Smurrayinchester 09:36, 10 December 2015 (UTC)

Smurrayinchester. What are the "two land neighbours"? The only one I can think of is the Republic of Ireland and the United Kingdom article seems to confirm that. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 13:40, 10 December 2015 (UTC)

CambridgeBayWeather, Smurrayinchester's parenthesized mention of the UK was complete, so he'd reverted to taking about the US. Rojomoke (talk) 14:01, 10 December 2015 (UTC)

I completely missed the closing bracket after "invasion". CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 14:08, 10 December 2015 (UTC)

Forty rods to the hogshead? That sounds not only inefficient, but explosive. – b_jonas 10:29, 10 December 2015 (UTC)

We Americans usually say miles per gallon. I gather the British do too. No reason to conform to someone else's standard just to be conforming. Oh, and the length of a cricket pitch is 4 rods. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:28, 10 December 2015 (UTC)

We (or rather, the car manufacturers) do indeed still often refer to car performance in terms of miles per gallon (caution, Imperial not US gallon). Unfortunately, all our petrol stations now dispense in litres: I assume this is deliberate obfustication. {The poster formerly known as 87.81.230.195} 185.74.232.130 (talk) 14:28, 10 December 2015 (UTC)

However, we would usually say one chain or 22 yards. Alansplodge (talk) 12:14, 10 December 2015 (UTC)

Yes. I chose rods because someone mentioned rods. And the length of a cricket pitch is also one-tenth of a furlong. And I concur that switching to metric for gasoline is deliberate obfuscation. Thankfully that plague has not hit the USA yet. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:29, 10 December 2015 (UTC)

Just out of interest, in the UK, if you say right hand drive, it means that the steering wheel is on the right i.e the car drives on the left side of the road. Widneymanor (talk) 11:18, 10 December 2015 (UTC)

Correct [6]. Alansplodge (talk) 12:09, 10 December 2015 (UTC)

Banned-user trainwreck
The following discussion has been closed. Please do not modify it.
Forty rods to the hogshead? I doubt if Grampa would like it at all. That's 195 m per 245 L, i.e., a fuel consumption of 1255 litres per km. My largish V6 GM car uses about 0.9 litres per km. Of couse if you had the sense to use SI/metric, such estimating errors are very much less likely. 60.228.70.176 (talk) 14:02, 10 December 2015 (UTC) Yes, 40 rods is one furlong or one eighth of a mile and a hogshead seems to be 63 US gallons, so 504 gallons per mile. An M60 tank manages better than one mile per gallon. Alansplodge (talk) 15:56, 10 December 2015 (UTC) IIRC the reason why the UK moved to selling fuel in litres in the 80s - before it was required by legislation - was that the fuel became so expensive that the mechanical digits then used on the pumps couldn't turn fast enough to keep up. Of course, it does mean the price looks better as well. Richerman (talk) 18:19, 10 December 2015 (UTC) This has some more examples of vehicles which have better mileage [7]. It evidentally includes a LCAC hovercraft. However it also depends on your definition of Hogshead as it's claimed there's no standard one and in particular, no standard one for petrol or diesel (which our article supports). That said, the difference are small enough that you're not likely to even double the efficiency. Nil Einne (talk) 22:23, 10 December 2015 (UTC) One reason might be that manufacturers and retailers used the change to the metric system to downsize their products. For example, a 455-460 cubic inch car engine (7.5 liters) was considered among the largest before conversion, but when they wanted to downsize engines they switched to metric and the 5.7 liter engine became the largest engine available in many models. So, US consumers started to assume that anything in metric was that way to cheat them, and avoided buying such products. Requiring both types of units to be shown equally prominently, until all consumers adjusted to the new units, might be one way to solve that. StuRat (talk) 18:31, 10 December 2015 (UTC) Let us all adopt the FFF system.   → Michael J Ⓣ Ⓒ Ⓜ 22:20, 10 December 2015 (UTC) Nice theory, StuRat. And it might well be that some (dumb) Americans think that the metric system is about cheating the customer. But your theory isn't right. Manufacturers like GM, Ford, Chrysler up until the 1980's had the US market almost to themselves. They did not export US production (except in very small quantities in the luxury market), but they had factories in other countries. They got by with their unsophisticated big iron V8's up to 7.5 L in the USA, but their overseas factories never made engines that large. They made different, smaller, engines to suit local markets. Then the Japanese and European competition hit. Then Korean competion. To remain competitive, GM had to do a number of things. One was to standardise on a "World Standard" alloy V6 in 3.5 litre capacity. But is is a far more sophisticated design than their old big iron. More power and less weight so such up the power. I have the 3.5 L engine in my car, it is much more responsive than the old 5.7 litre iron V8. And with much better fuel consumption. Another example: Plywood and MDF used to be made in a standard size 4 foot by 6 foot (914 x 1828 mm). When metrication came to this country decades ago, the factory machines still of course made the size they were built up for, with limitted adjustment range. So shhets were just sold in size 915 x 1830 mm for the next 20 years or so. Later on the industry standardised on 1200 x 2400 mm. Yep, they went up, not down. Sawn timber sold "undressed" is and was alawys sold over size anyway, so you can plane it. One more example: Milk was sold in 1 pint bottles (568 mL). After metrication, the container size was rounded UP to 600 mL. Yep, they went up, not down. And no, they didn't call a 568 mL container a 600 mL container - thet would be illegal. So, StuRat, you've got it wrong. 60.228.38.228 (talk) 01:21, 11 December 2015 (UTC) US car manufacturers surely had many reasons for downsizing the engines, but that's not relevant here. They determined that US consumers would not be willing to pay as much for cars with the new, smaller engines, so they decided to disguise that fact by moving to metric. This is what left a sour taste in consumer's mouths. StuRat (talk) 04:40, 11 December 2015 (UTC) My country went metric decades ago. Marvellous. So much easier. So much less error prone in calculations. The goverment had the schools teach the MKS metric system essentially one generation prior to metric weights and measures legislation, so when things started to be sold in metric sizes, we all went, "about bloody time!" MKS is of course 99.99% the same as SI metric. 60.228.38.228 (talk) 01:28, 11 December 2015 (UTC) How do you divide a meter into thirds? With our system, it's easy. A foot is a third of a meter. 4 inches is a third of a foot. Nothing error-prone about it. You've been brainwashed by conformists. ←Baseball Bugs What's up, Doc? carrots→ 03:15, 11 December 2015 (UTC) Why stop at thirds? Let's all move to a system that makes it a snap to divide weights and measures by 19. -- Jack of Oz [pleasantries] 07:20, 11 December 2015 (UTC) The biggest drawback to anarchy is that it is extraordinarily conservative. And while the U.S. scarcely seems like an anarchy, when it comes to a certain subset of business practices, the legislature doesn't feel like it should be involved. Constitutional provisions like freedom of expression and institutional doctrines such as local control of schools probably hinder a 'metrification' program. There's also just a loss of morale involved: as the result of past desultory efforts toward metrification, people don't think it's going to happen - say, manufacturers assume customers want to hear how many BTU a furnace puts out, and customers assume it is more useful to compare BTUs than a different unit that is less readily researched. They assume, I think, that any metrification effort will just be so much noise by a few people looking to collect a paycheck, soon forgotten. (There's an article Metrication in the United States that doesn't touch on any of these points; I'm just giving my feeling) That doesn't mean that where metric is genuinely made universally available - like the ml volume on product labelling - that it can't catch on eventually. Wnt (talk) 02:51, 11 December 2015 (UTC) The basic flaw with metrics is that they are not based on "human" measurements. We used them in school science classes, decades ago; and as you note, they tried to get the public to "think metric" in the 1970s. It didn't work. And until (or if) the public decides to start thinking in the artificial realm of meters and centimeters instead of the more natural yards, feet and inches, it still won't work. Maybe in a few generations. But not yet. ←Baseball Bugs What's up, Doc? carrots→ 03:13, 11 December 2015 (UTC) That argument would make more sense if the rest of the world hadn't switched. Well, other than Liberia and Burma. Mingmingla (talk) 03:28, 11 December 2015 (UTC) Quite right. And Bugs missed my point. My country phased it in, carefully planned. First, they taught the MKS sustem in schools. So you had a whole lot of school leavers accustomed to doing all manner of calculation and thinking in metric. THEN, they passed laws requiring anything sold or purchased to be specified in metric dimensions. Dual labelling was permitted only for a short time, and the metric dimensions had to be more prominent. If you just introduce the metric system overnight, young people will adapt quite quickly, but older people will resist it sufficiently to make it necessary for dual labelling for years, which defeats the whole idea, as everyone just keeps thinking the old way. If you just teach metric in schools but not pass laws to compell use, then again it will fail, because as soon as people leave school, their elders & bosses will make them forget it. But what is a mystery to me is why Americans don't see how easy the SI metric system makes everything. And how much money it saves in commerce and industry. — Preceding unsigned comment added by 60.228.38.228 (talk) 03:49, 11 December 2015 (UTC) I don't like centimeters, they're too small. But they're too big for precision work. I like inches and millimeters. And I'm perfectly capable of understanding the metric. Sagittarian Milky Way (talk) 04:03, 11 December 2015 (UTC I think our liquid measurements are awesome, too. It goes cup, pint, quart, half gallon, gallon. A convenient name for every power of two in the range where you need it most. There's also an ounce, 1/8th of a cup; tablespoon 1/3rd ounce; teaspoon 1/3rd tablespoon and that's 5 milliliters. Sagittarian Milky Way (talk) 04:11, 11 December 2015 (UTC) The pound is a better base mass as it's more in line with the size of the amount of food or drink you consume in one sitting. It's also a moderately large beer (which used to be sold in pints that equal exactly 1 pound). It's equal to 4 smartphones or 1 tablet (approximately). A kilo would be a huge drink or meal (half a 2 liter soda bottle!) Sagittarian Milky Way (talk) 04:21, 11 December 2015 (UTC) A horse is 1,000 pounds. If it's 4 digits, it can't be lifted. A ton is 2,000 pounds, slightly smaller than your tonne of 2,204.68 pounds. An ounce is 1/16th ounce (because it's based on a pint not a cup, remember). Non-metric sucks at small masses. People just use grams for small things like base metal coins unless they're really stupid. Sagittarian Milky Way (talk) 04:27, 11 December 2015 (UTC) An acre more closely corresponds to the smallest area that looks like "land" when it's square and empty and you stand in that middle of it. It's what you can plow in one day with an animal. A hectare is a bit bigger. A kilometer is a bit small for road measurements and larger geography. A mile is better. Fahrenheit has a more useful distribution of degrees for weather. Who needs all those Celsiuses above 58 or something? They never happen. It's a waste of space. Sagittarian Milky Way (talk) 04:35, 11 December 2015 (UTC) So, I can plough 1 acre of land with an animal (presumably a hourse or an ox)? Gee that's real good to know. Nobody in this country has used animals to pull ploughs for about 100 years. We use tractors with a power output of hundreds of horses. Same in the USA. In fact the USA produced the first commercial tractor. You can always find a few minor advantages in almost anything. You might say the 1952 Chevrolet is better because it has strap handles in the back for Granny to hang on to. They don't put the strap handles in now. I liked the 2-way tailgates on the 1970's Ford station wagons. However, I'll stay with my 2007 GM car - it's very considerably safer, has a lot more acceleration, much better fuel consumption, much better paint, far better handling, really good stero system standard, etc etc. 1.122.35.134 (talk) 06:33, 11 December 2015 (UTC) Americans are not opposed to using the metric system voluntarily. Our drug dealers have long sold cocaine by the gram and a "kilo" is a significant quanity of marijuana. Our wines are sold in 750 milliliter bottles. And in the old days long before digital, many serious photographers used 35 mm cameras. What Americans object to is being forced to use the metric system. The metric system is neither sacred nor inherently superior in every situation. Cullen328 Let's discuss it 07:12, 11 December 2015 (UTC) That sounds a bit straw man-like to me. Who has ever tried to force the USA to go metric? How would they go about actually achieving that goal? -- Jack of Oz [pleasantries] 07:24, 11 December 2015 (UTC) The Australian IP contributor has been extolling the virtues of compulsory metrification. That's not, of course, a question of forcing the United States to go metric, from outside the United States, but it is still a matter of force. --Trovatore (talk) 07:27, 11 December 2015 (UTC) "The Australian contributor" is our old friend WickWack, incidentally. Perhaps it's time to bring this discussion to a close. Tevildo (talk) 09:26, 11 December 2015 (UTC) Tevildo thinks, apparently, that there is only one person in Australia, called "WickWack". Actually, there's about 25 million of us. About one tenth the population of USA, so for every 10 American contributors to Wikipedia, there ought to be one Australian. Or perhaps "WickWack" is Tevildo's term for Australians. 1.122.35.134 (talk) 14:15, 11 December 2015 (UTC) Your MO and specific location say "WickWack". ←Baseball Bugs What's up, Doc? carrots→ 16:02, 11 December 2015 (UTC) JackofOz, that would involve laws and regulations requiring that traffic signs give speed limits in kilometers per hour, rather than miles per hour. Or that signs must state that a large city is so many kilometers away, instead of so many miles away. Or selling gasoline and milk measured in liters, not gallons. Or meat, fish and vegetables weighed by the kilogram, not by the pound. Or that tape measures must be denominated in decimal fractions of a meter, not feet, inches and fractions. And so on. Force of law and regulation is the "force" I was referring to. Americans rebelled quite decisively against such laws when they were tried here a few decades back. Cullen328 Let's discuss it 07:57, 11 December 2015 (UTC) That doesn't really seem to answer the question though. Why are Americans happy to be forced to used their old units mostly adopted from the British despite the numerous flaws of said units, but unhappy to be forced to use the metric system which is better in most ways (particularly since for better or worse, nearly all modern human cultures use the decimal number system for everyday use)? That ultimately is at the hard of the question and saying "they preferred to be forced to use the old system rather than forced to use the metric system" isn't a particularly satisfying answer. It also doesn't really address the issue of why Americans are unhappy to use the metric system voluntarily in most areas of life where it is mostly unrelated to "force" again despite the numerous advantages which the rest of the world have noticed, since in most countries regardless of how they go there, few people want to return to any old system and think the US units are frankly dumb. Again that is at the hard of the question. (Personally I think several earlier answers have largely address these issues, but the point remains, your comments don't really seem to have helped answer the question.) Nil Einne (talk) 08:55, 11 December 2015 (UTC) The original question assumes facts not in evidence. Cullen disputed the premise of the question, pointing out, correctly, that Americans do in fact use the metric system quite happily. We're just opposed (most of us) to having it written into law. I think that was a useful response to the question, though, as you say, it was not directly an "answer" to it. --Trovatore (talk) 09:14, 11 December 2015 (UTC) That an acre is 1 day of plowing with an animal is a lot more well known in the US (even in the city) than in metric countries (yes, ox or horse). I think that's how the unit started - it's 1 chain times 1 furlong exactly (a furlong is a "furrow-long" — the length of the furrow in the field) the 20x200 meter field shape was because turning the plough around was a pain in the ass. A hectare is what 2.59 acres or something? If I started the metric system I would've made the decimeter the base unit, or maybe 100 millionth of the meridian or circumference (20 or 40 centimeters). You used 10 millionth of the half meridian instead so it's 100 centimeters. One thing that metric is awesome for though (besides huge, tiny or scientific measurements) is cubic measurements (1 L = 10 cm3 = 1000 mL = 1 kg H2O ¤ 1 m3 = 1000 L = 1000 kg H2O = 1 t H2O ¤ 1 mL = 1 cm3 = 1 g H2O). It's still inferior for culinary use. I'm not sure if converting by 10s, 100s, etc. is a big a benefit as metric proponents say it is. If everyone in Britain can get good at driving a freaking clutched car and converting by 12s, 20s, and 240s then humans can get used to converting by the 2s, 3s, 4s, 8s, 12s, 16s and 36s in US measures if they grew up with it. Metric is part of the culture of 99% of the countries now though so they shouldn't change back and Customary with a little metric where the Customary is unusually cumbersome is part of American culture still and shouldn't be eradicated like Welsh (or Manx, Scottish, Cornish, Gaelic etc.). Americans don't mind to put skyscrapers everywhere yet love low-tech crap like classic rock, 8 liter V8's and Republicans (and inches). Europeans like to keep their surroundings historical (not that that's a bad thing) yet love advanced things like electronic music, metric, and progressivism. Even their logos, news programs and stuff look awesome and futuristic. The high tech stuff is probably a foil for all the pre-industrial stuff they see all day. Potato/potahto. We're the last country of any import to use traditional units, so what's so wrong with that? (They were teaching me 5,280 feet in a mile at age 6, too. That probably seems ridiculous to you) Sagittarian Milky Way (talk) 08:05, 11 December 2015 (UTC) The advantage of the metric system is very much more than the 10^n multiplier - though that it is in itself a strong advantage. The "customary units" system as the USA calls it involves lots of weird looking constants in just about every calculation, and you need a calculator, or pencil & paper to do them long hand. In the SI metric system there are no weird constants, just the occaisonal pi. In lots and lots of routine calculations, you can (if you were taught properly in primary school) do them in your head. And the SI metric system facilitates dimensional analysis, which is incredibly powerfull at showing errors in formulas, whether incorrectly remembered or worked out on the spot. There's metric and there's metric. All metric systems had x10^n multiplication, but as I said, that's only part of it. 100 years ago the Europeans used theh CGS metric system - an improvement over customary units. In the 1950's they changed to the MKS metric system, a worthwhile improvement over CGS. Then, on about 1970, the Europeans changed to the SI system, a minor improvement over MKS. So three lots on improvements in total over customary units. And the silly Americans still stick with customary units. Its a bit like as if Euros changing over the years from a horse to a 1920's car, then a 1950's car, then a 1970's car. Getting better each time. But the silly Americans are still saying "nobody forces us to do anything, we stay with our horses because we like them." 1.122.35.134 (talk) 09:29, 11 December 2015 (UTC) It does not usually require paper or a calculator! When you grow up with it it's way easier than it looks. Even more so for people who use them frequenter than average like carpenters and builders. They would soon instantly know how many feet it is when they see 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78, 84, 90 or 96 inches and maybe higher and also the reverse. Even if you don't know the number exactly you would have a good estimate for how many yards in a mile (1,760) just because you drive all the time and the road signs are all in yards when it's less than a quarter mile (440 yards). And similarly for other things. Sagittarian Milky Way (talk) 09:52, 11 December 2015 (UTC) And I'm sure that many Americans are perfectly capable of mentally converting any common metric units to the other common metric units. Sagittarian Milky Way (talk) 09:58, 11 December 2015 (UTC) There is really no such thing as one system of measurement being better than another. It can be better for certain purposes, sure. Use whatever works best for you, and then learn how to convert units, so you can talk to people who use different ones. It's really not hard, and it's unreasonable for you to demand that others give up units that are convenient for them, just to save you some utterly trivial arithmetic. --Trovatore (talk) 09:34, 11 December 2015 (UTC) That paragraph is so true. Sagittarian Milky Way (talk) 09:52, 11 December 2015 (UTC) The US uses metrics where it makes sense to. But the argument that "everyone else uses it" is bogus - it's the conformist argument. Americans don't conform to someone else's system just because those someone-elses think we should. ←Baseball Bugs What's up, Doc? carrots→ 10:12, 11 December 2015 (UTC) The American assertion that they can't be forced to do something, and won't accept laws that make the metric system mandatory, is pretty daft when you look at the big picture. The USA used to have a very sound economy, because they used to make everything. Now they make less and less. They buy things from China, and borrow money from China. So the big question is: why have they becaome so uncompetitive? Not using the metric system is part of it. Forget silly old Granpa and his hogsheads, the metric system reduces the cost of doing commerce, reduces the cost of research and development, and reduces the cost of making things. Though I admit that customary units is only a small part of the reasons why manufacturing in the USA is now uncompetitive. The big reason is that, yes, they passed laws about polution and occupational health and safety that are beyond what other countries have - over the top in fact. Over a certain point, safety cannot be increased by legislation - it just increases costs. So on the one hand they reject a law that would make things easier (metrication) but totally accept environmental and OH&S laws that ruin them! Makes no sense at all. And makes the claim above that they can't have a (good) law null and void. 1.122.35.134 (talk) 10:52, 11 December 2015 (UTC) Nobody forced virtually all other countries to go metric. They went metric because it simplifies things and lowers costs. Nobody is forcing America to go metric. We just find it hard to understand why they won't. 1.122.35.134 (talk) 10:52, 11 December 2015 (UTC) American companies, and indeed American consumers, don't accept that you could be prohibited from writing the words "ONE GALLON" on a container you're selling. Nor would they accept that you ought to be banned from selling exactly that much liquid, and required to sell more or less instead. And though I don't know, I'm awfully skeptical that the Chinese accept any such ban either - their country isn't really renowned for business regulation - but as you say they have an export focus, so I feel sure they're willing to provide whatever units the rest of the world wants to buy in. Wnt (talk) 14:26, 11 December 2015 (UTC) China is an SI metric country. Importers in other countries can have the products re-labelled or specially labelled (by the manufacturer) if they wish. Chinese compliance is tighter than the Japanese - a metric country but who has its own standards for many things. Foe example, China makes its' nuts and bolts to Euro metric standards, but the Japanese have some odd ones, that are metric, but not European metric. A bit like the British Association standard for small nuts and bolts - again, it's metric, but not standard metric, and incompatible. 1.122.35.134 (talk) 16:00, 11 December 2015 (UTC) Sorry, what's the improvement of MKS over CGS? There is the whole electrostatic versus electromagnetic difference between electrical unit definitions, but as MKS per se technically doesn't specify electrical units, that's not an intrinsic benefit. I'm not sure what other worthwhile improvements there are by using the metre over the centimetre while simultaneously going from the the gram to the kilogram. -- 160.129.138.186 (talk) 16:14, 11 December 2015 (UTC) A question that I asked some time ago, which was never really answered, was "Why does the US use thousands of pounds when talking about trucks?" https://en.wikipedia.org/w/index.php?title=Wikipedia:Reference_desk/Miscellaneous&oldid=627531150#Why_does_the_US_use_thousands_of_pounds_when_talking_about_trucks.3F So if the US was to go completely metric, would they refer to trucks in thousands of kilograms or tonnes? As an aside, I grew up in a metric country (Australia) and moved to Britain. Even after 20+ years, I still use metric every day. My recipe books are metric, my rulers and scales are metric, and I don't need to convert to the other system. Driving isn't a problem as the speedo is just a number and the appropriate speed is posted on the road. So long as the number on my speedo is the same as the posted number we're good! I find it funny when they say a car gets X miles per gallon, as you haven't been able to buy a gallon of petrol since the late 1980s. TrogWoolley (talk) 11:35, 11 December 2015 (UTC) An interesting question, because when you look at all sorts of international standards & usage conventions, it seems that the USA just likes to do everything "the American way" i.e, different to the Europeans. There is seldom any real reason, they just do things differently. Since truck capacities and truck loads are called out in thousands of Kg just about everywhere, perhaps the Americans would do the same, as it is sensible, or perhaps they would go for tonnes, just to be different? 1.122.35.134 (talk) 11:58, 11 December 2015 (UTC) Here is an interesting article from only last year on this very topic. --Jayron32 12:43, 11 December 2015 (UTC) The "acres" given above are an example of something that will never change. If you look for a home in the U.S., most of the time you're looking at acre lots, half-acre lots ... and those lots are going to stay the same size, especially because as a consumer in many places you'd pretty much have to know someone in local government to be able to subdivide them. If someone is selling ".404 hectares", the consumer will probably ask you how much that is in acres ... alternatively he might think he knows, in which case either he's right, in which case you've gained nothing, or he thinks it's more land than it is, in which case he might waste your time before he looks in more detail and changing his mind, or he might think it's less, in which case he goes right past your listing without stopping. I don't see any way that listing property in hectares will result in anything but pain for the seller. Even if a developer subdivides in odd-sized lots, there's no particular reason to use hectares. Wnt (talk) 14:37, 11 December 2015 (UTC) And there's no particular reason to use acres. Do you measure your house floor area in acres? I guess not. At one time, residential land in Australia was sold in approximate half-acre or quarter acre lots too. It was always approximate because town planning is and was always done "pre-calc", which means done on paper without regard for slopes, drainage, etc. Then when the land is surveyed, the surveyor measures the actual on-the-slope area. I bet it works that way in the USA too, because it is so sensible. You can hardly expect the planners to know the exact area before its surveyed. But since we went metric decades ago, nobody under 60 years of age really knows what an acre is. We mostly know what a hectare is (10,000 m2 - 100 good male adult paces on a side), and we know what a typical modern city r4 ("r4" is a standard town planning residential scheme - 4 dwellings per 1000 m2) land parcel is (160 to 250 m2), But, if you want a house of so many square meters floor area, the usual 85 m2 or so for a 2-car garage, room for the x-many square metres swimming pool, and a yard for the bar-b-q, you can mentally tot it up in the blink of an eye and visuallise the how realtor's offering will stack up. No, it's rather the non-metric system that will cause the seller (and the buyer) pain. Note that the hectare is not an System Internationale unit, it is a semi-obsolete European unit. If the USA was to go metric, properly, they would be measuring land in square metres. 1.122.35.134 (talk) 15:42, 11 December 2015 (UTC) House flooring is typically given in square feet. Lot size is typically given in acres or fractions thereof. Unless we plan to export land, there's no monetary reason to switch to square meters and hectares. ←Baseball Bugs What's up, Doc? carrots→ 16:00, 11 December 2015 (UTC) Yeah, I thought so. So you have to convert acres to square feet in order to figure out how to use the land. Not a big deal perhaps, we know an acre is 43,560 square feet. But why not measure both in the same units and make it easy? It's all these weird conversion factors in US customary units calculation that make mental arithmetic difficult and facilitate error. 1.122.35.134 (talk) 17:16, 11 December 2015 (UTC) Different units exist in different sizes to facility human understanding. Humans have a limited number sense, whereby there is a difficulty in internalizing and making meaning out of very large or very small numbers. One could for example measure everything using a single unit, say the meter. The problem becomes expressing the size of a bacteria, and the distance to Mars, only using meters interferes with people's ability to "internalize" such numbers in a way that makes sense to them. Most people can only deal with numbers of a limited number of digits (say 3-4 digits on either side of the decimal place) before their brain can no longer intuitively connect the string of digits to its real size. Thus, a measurement of 1,500 kilometers may be more meaningful to a person than 1,500,000 meters, or 1,500,000,000 millimeters, though they are all equivalent. All measurements exist for the convenience of the people using them, people will tend to adopt a measurement system which is convenient for their own purposes. Expressing small areas in square feet, and large areas in acres, is useful in this regard: people know how big a square foot is. They know how big an acre is. So for small numbers of each, they can visualize, for example what a 1500 square foot house should look like, and also what a 3 acre plot of land should look like. The human brain has a harder time conceptualizing what 130,000 square feet looks like, or what 0.034 acres looks like, even though they are equivalent. The purpose of different sized units has little to do with how they facilitate conversion (though, I fully agree that the metric system wins hands down there), but with how the different sized units facilitate understanding of the connection between size and number. For further reading on this topic, these articles are all about the problems with the human mind and conceptualizing large numbers: [8], [9]. Also related is the notion of The Magical Number Seven, Plus or Minus Two, which is the landmark paper on the limits of human information processing; the number of digits in a number that a person can make "sense" of is closely related to (though not directly addressed by) the limits discussed in that paper. The way the human mind estimates the size of things related to number is called Subitizing, and while there are techniques which can be used to "train" the mind how to do it better, natural human limits on the ability to do so is limited. That's why people don't express everything in the same units. --Jayron32 17:37, 11 December 2015 (UTC) Also, crop yields in America are usually given as bushels per acre, while crop yields in Europe (and maybe elsewhere) are usually given as kilograms per hectare. Hectares are alive and well, unless they are no longer growing crops in the rest of the world. ←Baseball Bugs What's up, Doc? carrots→ 16:07, 11 December 2015 (UTC) The Hectare is not an SI unit. Look it up and check. The title deeds for the land I own are in square metres. The town planning scheme maps, sewage and drainage plans, etc are all in metres and square metres. Nothing official is in hectares. I suspect this is part of the problem with discussing this kind of issue. Americans think there are two systems - their system (which they call "customary units") and the "metric" system. In fact, there are many metric systems - local systems, CGS, MKS, and SI (= MKS improved). European experience and carefull thought by their standards bodies led in an evolutionary way to SI - the World standard since about 1970. If you are going to try and mix old metric systems units up with SI, or confuse them for SI, then naturally you will get less advantage than you will with full compliance with SI. A bit of googling showed that Australian farmers variously rate their yields in kg/Hectare, and tons/hectare. kg/m2 would be more compliant with SI (for wheat, 0.2 to 0.3 kg/m2 is typical), but it probably doesn't much matter, it's a dead easy conversion (1 tonne/hectare equates to 0.1 kg/m2), yields in any given geographic areas should be much the same, and when they sell it, the grain buyer is only interested in total weight and moisture content. 1.122.35.134 (talk) 17:16, 11 December 2015 (UTC)

Fellow contributors, may I implore a few of you to pause, research some referenced answers, and then either resume this discussion or relocate it to a different place?

Here is The United States and the Metric System, published by NIST (our Government's agency that standardizes weights and measures, part of our Department of Commerce). Some facts: publications of the Federal Government have been using metric-like units since at least 1800; the metric system is actually used as the standard to define the "conventional" units like inches and pounds. At several times in the 1970s and 1980s, specific legislation was attempted to mandate metric units: for example, see the history of the Metric Conversion Act of 1975.

The original question asked why many people are opposed to metric units; this is a faulty premise. We have used metric units for a long time for many tasks. We do not use them for every task. Sometimes, the metric system is just less useful, particularly when decimalized math is not relevant to the problem.

There has been a lot of discussion of miles, acres, and gallons... but bear in mind that Systeme Internationale is a complete set of physical units. Has anyone ever tried to meter a camera's photographic exposure using candelas? That's the SI unit. Give it a shot some day. There is more to this story than simple conversion between cubic-centimeters-of-water and grams-of-water.

Nimur (talk) 17:12, 11 December 2015 (UTC)

Bird identificaton

Can anybody identify the bird in the two pictures, pic one, pic two. It was found in Ulukhaktok, possibly yesterday but I'm not sure yet. It has webbed feet so it's obviously some sort of waterfowl. Could it be a guillemot? I don't have any measurements but the glove would be about 25 cm (9.8 in) long. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 11:08, 10 December 2015 (UTC)

It was found yesterday. Of course normally the only birds left at this time of year are snowy owls and ravens. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 14:02, 10 December 2015 (UTC)

It turns out to be a juvenile common eider. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 16:09, 10 December 2015 (UTC)

Ah yes, a duck is much more difficult to identify when it doesn't walk like a duck and quack like a duck anymore. – b_jonas 10:13, 11 December 2015 (UTC)

Are smiling faces more attractive than not-smiling faces?

It seems to me that, when people smile, their faces become more attractive or prettier. Is it me, or is there an objective truth behind this? 140.254.136.179 (talk) 15:40, 10 December 2015 (UTC)

Yes; see Study: Smiling Makes You More Attractive, and referring to earlier research, Eye contact and a smile will win you a mate. Alansplodge (talk) 16:14, 10 December 2015 (UTC)

Also, smiling watches is an interesting fact about "smiling".216.80.117.134 (talk) 16:26, 10 December 2015 (UTC)

Note however that these are recent studies, and that it is not necessarily a universal. Smiling was rarely used for portraits as it was considered mischievous or even the un-trustworthy. [10] Extract: "By the 17th century in Europe, it was a well-established fact that the only people who smiled broadly, in life and in art, were the poor, the lewd, the drunk, the innocent, and the entertainment." So smiling was not necessarily considered attractive to all parts of society. --Lgriot (talk) 12:55, 11 December 2015 (UTC)

Why is it so hard to walk on all fours?

I tried to walk on all fours. I just couldn't do it. My legs were much longer than my arms, and walking was just not comfortable, and running seemed impossible. 140.254.136.179 (talk) 15:48, 10 December 2015 (UTC)

Because humans evolved over time to have a body organization that favors Bipedalism. How this came to happen to YOU in particular is covered at Human skeletal changes due to bipedalism. --Jayron32 16:14, 10 December 2015 (UTC)

However, many reports of feral children suggest that they preferred to walk on all-fours, so possibly these skeletal adaptations can be overcome with practice. Alansplodge (talk) 16:20, 10 December 2015 (UTC)

And I found a documentary called The Family that Walks on All Fours. Alansplodge (talk) 16:38, 10 December 2015 (UTC)

The singular of "data" is not "anecdote". By that I mean that one human (or a small number of countable humans) likes to walk on all fours is not meaningful when considering the properties of humanity. See Generalizing from the particular for the problem with such thinking. --Jayron32 16:40, 10 December 2015 (UTC)

Alan said it was possible, which even one case demonstrates to be true. As for generalizing it to the entire human population, if your argument is that it's possible for some humans, but not all, then you would need to demonstrate why. For example, are the proportions of those who walk on all fours significantly different ? StuRat (talk) 17:10, 10 December 2015 (UTC)

As noted, being possible does not mean it's useful or relevant to drive behavior or understanding. For example, it is literally possible that I can win the lottery tomorrow, but that fact does not mean it is useful for me to buy a lottery ticket. Quite to the contrary, the data makes it clear that doing so makes me worse off, because statistically, I'm far more likely to get poorer, and often significantly so, merely by thinking that the possible is what should drive behavior and not the likely. Studying and explaining the likely is a more useful act than the possible in this case, since the OP asked why HE couldn't walk on all fours. If the OP were asking what they could do to improve their finances, you would NOT recommend he start buying lottery tickets, you'd instead recommend learning about how most people improve their finances in reliable ways. For exactly the same reason, when wanting to answer why the OP walks the way he does, we take the bulk of humanity into account, not the freak occurrences. --Jayron32 17:29, 10 December 2015 (UTC)

You are still assuming there is something fundamentally different about those cases, beyond just having practiced, despite providing no references to back up that assumption. Occam's razor applies here, meaning assumptions of differences require actual proof. StuRat (talk) 18:21, 10 December 2015 (UTC)

I've made no assumptions. Instead, I've refused to engage in the validity of generalizing from the particular, a well demonstrated fallacy. Which I did reference to so you could read about. You, on the other hand, continue to assert that it's a valid means of drawing conclusions, in direct contravention of accepted logic. Also, you'll note, that I provided references to answer the OP's question directly, so they could read about it and draw their own conclusions, and did so from the beginning. Which is something you last did...lemme check... never... --Jayron32 19:50, 10 December 2015 (UTC)

That you are unable to see the assumptions you have made is not something I can correct with a reference. StuRat (talk) 04:43, 11 December 2015 (UTC)

I'd like to see one or more picture of feral children actually walking on all fours, as opposed to "reports" of it. The average infant is likely to crawl on hands and knees, as even at a very young age their legs are longer than their arms. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:23, 10 December 2015 (UTC)

Oxana_Malaya has lots of photos and videos of her, e.g. here on youtube [11]. She does seem to use her knees more than her feet when moving around, though sometimes she does use a gait similar to the The Family that Walks on All Fours, which is definitely a two-handed, two-footed "walking on all fours". That family really is a fascinating case, I recommend watching at least a few minutes at the link above to see them walk. SemanticMantis (talk) 19:27, 10 December 2015 (UTC)

The question was "why is it so hard" not "is it possible" so I'm with Jayron here, just because some feral children and one family "do it", doesn't really have any relevance to the question "why is it so hard?". Vespine (talk) 21:22, 10 December 2015 (UTC)

I'm mostly with Vespine and Jayron32 here except that I would say that I think the links and comments from Alanspodge were mildly useful to the discussion. While it didn't answer the question of "Why is it so hard to walk on all fours?", they did relate to the points the OP made in their comment in that it does seem some people, perhaps most people, are able to do it better than the OP. The sources don't demonstrate this so we have no idea, but while I only skimmed through the video, I didn't see anything to suggest they had any unusual genetic body types that made walking on all fours easier, nor with feral children. (It possible their parts of their bodies developed in such a way to make it easier, due to practicing it since childhood.) This doesn't mean it's ever easy or particularly suited to the human body type. While it's possible this is bias from experience, the family odd style of walking still didn't seem to work that well. StuRat's comments do seem unnecessary and unhelpful. Nil Einne (talk) 22:11, 10 December 2015 (UTC)

You said "I didn't see anything to suggest they had any unusual genetic body types that made walking on all fours easier". I agree. Jayron, on the other hand, in saying we can't assume that all people have this capability is suggesting precisely that there is something fundamentally different about the people in the video that makes them capable of this, while other humans are not. I simply asked for a source to support this assumption. StuRat (talk) 04:50, 11 December 2015 (UTC)

Your summary of your and Jayron32's comments isn't particularly accurate. Nil Einne (talk) 08:35, 11 December 2015 (UTC)

Per Nil Einne, I didn't say, to quote you, "there is something fundamentally different about the people in the video that makes them capable of this, while other humans are not." I said 1) we can make no assumption in any direction. To refuse to commit without evidence is NOT the same thing as to commit to the negative assumption, as you are claiming I have done. What I am saying, have said, and will continue to say is that there is no position to be taken, either in the affirmative or negative, on any assertion without evidence. Not that you'll listen to this, because your past and continuing behavior for years has indicated that you aren't terribly interested in improving your understanding of the world, but I will repeated it just to prove to the world that you have been informed of this: There is a difference between not committing to a stance and committing to the negative position. Learn the difference if you want to not look foolish. 2) I also said that the point is not terribly relevant to answering the question and gave sound links to logical issues with using anecdotes as evidence for making generalized statements about humanity. --Jayron32 11:38, 11 December 2015 (UTC)

You said the observation "is not meaningful". If you meant it "may or may not be, and more study would be needed to establish if it is", then you should have said that. StuRat (talk) 15:38, 11 December 2015 (UTC)

The observation is not meaningful to answering the question. It may be meaningful to answering a different question. --Jayron32 15:55, 11 December 2015 (UTC)

Please note that I wasn't disputing Jayron's pertinent links, I just thought it would be interesting to see the other side of the coin. Thanks to those who have spoken in my defence. Alansplodge (talk) 08:58, 11 December 2015 (UTC)

Aye, I understood. I was only responding to Bugs' comment about pictures, of course we're bipedal and that's the main answer, but that doesn't mean we can't share additional relevant references for context and discuss slightly tangential issues (e.g. feral children) SemanticMantis (talk) 14:58, 11 December 2015 (UTC)

Concentration of minerals in the Earth crust

We know how our solar system came about, it started with an explosion of a supernova that blew out enormous amount of hydrogen, maybe just a mix of protons and electrons, and perhaps some helium. Along with that it blew out for months or perhaps years some gamma radiation. As a result heavy elements were synthesized. Then the gravity helped to create a central point and some chunks of material began to rotate around it. There was this proto-planet Earth and after a few million years another big chunk slammed into it thus creating the moon. I assume the Earth liquefied because of the blow but then slowly cooled. Why do we have concentration of minerals in the Earth crust? It would be logical to assume that ALL elements should be distributed equally everywhere like when you drop a piece of sugar in a tea glass and stir it thoroughly. I think it is true for aluminum if I am not mistaken. Instead we have places where the elements like copper, iron and others are plentiful making industrial mining profitable. In Russian Ural Mountains there is a mountain that consists entirely of magnetized iron. It won the World War II for them. They converted the chunks of the mountain into T-34s right there. Why is it so? Why do we have copper deposits in some places but not others. The total chaos of creation should have mixed elements equally through the Earth and this is clearly not the case. Thanks --AboutFace 22 (talk) 23:55, 10 December 2015 (UTC)

Have a look at Ore genesis. Dolphin (t) 00:25, 11 December 2015 (UTC)

• See The Elements: Their Origin, Abundance, and Distribution by P. A. Cox, and come back if you have any complaints. This book is worth its weight in gold, although you need not spend so much as its weight in aluminium to acquire it. μηδείς (talk) 04:20, 11 December 2015 (UTC)

For why the Earth isn't homogeneous, try Planetary differentiation. Mikenorton (talk) 12:48, 11 December 2015 (UTC)

We have an article on Magnitogorsk, which alas is very short on geology. For specifics information about the raising of the mountains during an arc-continent collision see [12], which is freely accessible and very detailed... except about how the iron fits into the picture, which it discusses not at all. (the general idea is discussed at forearc but I am wary that I may misunderstand some vital details) The Cox reference suggested above is a great idea; regrettably Ошибка: не удалось открыть страницу. Wnt (talk) 13:45, 11 December 2015 (UTC)

Not directly related to your central question, but your description of supernovas is not really correct. Supernovas don't "[blow] out for months or perhaps years some gamma radiation", unless by that you're talking about the photons produced by the supernova traveling away through space (which will of course travel until they hit something, which for any individual photon could take billions of years, or never happen). The supernova explosion itself takes a few seconds at most. Supernovas do create heavier elements in the explosion event, but many elements heavier than helium are created inside stars during their lives by fusion reactions. See nucleosynthesis. And here's Crash Course Astronomy on the lives and deaths of high-mass stars. --71.119.131.184 (talk) 18:36, 11 December 2015 (UTC)

December 11

Calculating orbital distance based on 2 observations

[13]

The two observations show movement of the new dim object relative to Alpha Centauri A and B. So, why can't we find the movement, say in terms of arc seconds, then figure out how long it would take to move 360 degrees based on that, and derive the orbital distance from that ? Some potential problems I see:

1) This assumes it's in orbit about the Sun. If it's in the Alpha Centauri system, or not bound to either, then this won't work. (If in the Alpha Centauri system, it might have already made an orbit in the observation period, but then presumably we would have more observations).

2) This won't take acceleration into account.

3) Let's assume it's in our solar system. This doesn't consider movement towards and away from Earth (which is essentially the same as towards or away from the Sun, at that distance). Would movement toward or away from the center of our solar system change the calcs ? (I realize that this implies acceleration, but if that accel is only towards and away from the center, rather than normal to this direction, does that matter ?)

Also, a second Q: There are questions about why it wouldn't have been observed more often. Could it be varying in signal strength for some reason, in the frequency detected (short microwave wavelengths), such that it drops below the observation threshold ? StuRat (talk) 15:21, 11 December 2015 (UTC)

• The original paper is here. The authors aren't even sure that it is orbiting us – all they can say is that it's comoving with the Centuari system but doesn't seem to be bound to it. As for why it wasn't seen before, they suspect that it "could not have been detected with the VLT-NACO data [the last major survey of that area of space, done in 2004 to 2005] because, due to the intense glare from Cen AB, it was intentionally blocked out of view." This makes precovery very difficult - if you look at Figure 2, between about 2000 and 2010, it was almost overlapping the Centauri system. It's only now that it's moved further away from the star system that it's become visible. Smurrayinchester 15:53, 11 December 2015 (UTC)

(edit conflict) Let us assume that object is in orbit around the sun and that we as observers are roughly in the focal point of the ellips (i.e. comparatively close to the Solar System's center of mass). Then the orbit is decribed by Kepler's second law: $P\cdot {\tfrac {1}{2}}r^{2}{\frac {d\theta }{dt}}=\pi ab$ with P the period, r the object's current distance from the focal point (us) and a and b the semi-minor and semi-major axes of the ellipse. From the two pictures, the only thing we can directly calculate is ${\frac {d\theta }{dt}}$, so there are simply too many unknowns. Only if we assume that the orbit is circular (i.e. $r^{2}=ab$) can we find the orbital period, and, from that, the object's distance. - Lindert (talk) 16:04, 11 December 2015 (UTC)

Thanks. I take that the mean that movement (and hence acceleration) towards and away from the Sun does affect the orbital period. StuRat (talk) 16:08, 11 December 2015 (UTC)

Yes, you could say that; of course if you knew the acceleration, you'd also know the distance simply from Newton's law of gravity. - Lindert (talk) 16:34, 11 December 2015 (UTC)

My guess is that to predict where something is going to be in the future - you need to know where it is now, and it's velocity. Each of those requires three numbers (like X,Y,Z and dX, dY, dZ) - so you have a system of equations with six unknowns. If your observation is only a 2D thing (azimuth/elevation for example) then each observation provides only two "knowns" - so you need three observations to produce six knowns with which to calculate the six unknowns. SteveBaker (talk) 18:20, 11 December 2015 (UTC)

Yes, that is fundamentally true, but I doubt that three measurements is always sufficient. And for orbiting objects that are very far away, some of the information may be redundant, considering the accuracy of the measurements, because we pretty much know already that they will move in a 'straight' line across the sky, hence the third measurement may give us only one extra unknown. - Lindert (talk) 18:40, 11 December 2015 (UTC)