Wikipedia:Reference desk/Archives/Science/2016 May 12

= May 12 =

Percentage of Muslims that self-identify as British-first or muslim first
Out of Muslims living in Great Britain,what percentage of them identify as Muslim-first, and what percentage identify as British-first? — Preceding unsigned comment added by 70.180.208.48 (talk) 03:00, 12 May 2016 (UTC)
 * In other words, how many people identify as "Britons who are Muslim", and how many are "Muslims who are British" — is that what you're asking? Nyttend (talk) 03:50, 12 May 2016 (UTC)

Yes — Preceding unsigned comment added by 70.180.208.48 (talk) 04:08, 12 May 2016 (UTC)


 * In a recent survey 17% said their Muslim identity was more important than their British identity, 6% said their British identity was more important than their Muslim identity, and 76% said they were both equally important to them. http://survation.com/new-polling-of-british-muslims/ 81.132.106.10 (talk) 08:21, 12 May 2016 (UTC)


 * If you ask a silly question you usually get a silly answer. The value of such an answer in the real world is 0. The Quixotic Potato (talk) 16:36, 12 May 2016 (UTC)
 * This isn't a silly question, but it's much more humanities than science. It's addressing an aspect of cultural assimilation that's rather similar to the cricket test, although it addresses different aspects of the same basic issue.  Nyttend (talk) 02:46, 13 May 2016 (UTC)
 * It is a silly question, and the answer is meaningless. Take the same question, but replace Muslims with (for example) Jews or Jehovah Witnesses or whatever and replace Great Britain with another random country, for example Liechtenstein. Do you understand why the question is silly now? Feel free to disagree though! The Quixotic Potato (talk) 02:57, 13 May 2016 (UTC)
 * It's not exactly silly, it's more like hinting at the notion that Muslims are disloyal, and the question is possibly driven by the recent election of a Muslim as mayor of London. It's basically Trumpism. ←Baseball Bugs What's up, Doc? carrots→ 07:10, 13 May 2016 (UTC)
 * True, I used "silly" as a euphemism, but I am far too kind. I think that people who question the loyalty of the Jewish people in Liechtenstein are antisemitic idiots. I didn't know "Trumpism" was a new euphemism for this kind of hate, but it is quite fitting. My userpage contains a special message to Donald Trump. The Quixotic Potato (talk) 11:28, 13 May 2016 (UTC)
 * The question may be offensive to some, but it isn't silly or idiotic. After all, there has to be somebody who would far rather see Tel Aviv or Cairo prosper than London.  Some people actually have conflicting allegiances (and probably more often, none at all).  It is difficult to answer, for obvious reasons, but it should not be altogether unanswerable.  I think rejecting legitimate thought like this out of hand is not a way to suppress prejudice, but is more likely to inflame it.  If you want to stop prejudice, then you need to marshal and drill an army of counter-arguments, such as the number of Muslims who have died in military service or who have risked their lives in a civilian role.  If you feel it is beneath you to argue your case, do not be surprised to lose. Wnt (talk) 22:25, 13 May 2016 (UTC)
 * For all religions I know about I am an atheist/nonbeliever, and in general I am a theological noncognivist and an ignost (no, that is not a typo). I am incredibly lucky because I was born in one of the least shitty places in the world (Amsterdam, the Netherlands). I am Dutch by default, not by choice. My great-grandfather wore klompen and slept in a bedstee. I don't feel a special connection to people who happen to be from roughly the same geographical area (my country is only 200 by 300 kilometers by the way). Being an Amsterdammer and a netizen has had a far greater influence on me than being Dutch. See . You seem to be American; I have never visited your country but I am under the impression that in America nationalism is far more common than it is here. In 2015 a report was published that states that approximately 67.8% of the population in my country has no religious affiliation; the population of the USA is about 70% Christian. Are you religious? Of course I don't feel a special connection to other atheists; the best thing about being an atheist is that we are not members of a club. Do you agree with me that people who question the loyalty of Jewish people in Liechtenstein are antisemitic idiots? Would you have written the same thing if the question was about Jewish people in Liechtenstein (or Jehovahs Witnesses in Finland, or Buddhists in Greece)? The question is silly (I am using that word euphemistically), and the answer is meaningless. Feel free to disagree. Lose what? A hypothetical discussion that hadn't even started yet? Who decides? Is there a referee? Who cares? We are building an encyclopedia, no one is keeping track of the amount of times I "win" or "lose" a discussion afaik. Does "winning a discussion" mean that you actually have to convince someone? I have that famous Oscar Wilde quote on my userpage: "it is well to remember from time to time that nothing that is worth knowing can be taught". If you do not understand why the question is silly then I don't think I can help you with that. I wish I was as hopeful and optimistic as you are; you seem to believe that rational arguments are effective weapons against prejudice and stupidity. Maybe I am old and bitter, but in my personal experience the reality is far more complicated. I believe that if you want to stop prejudice you'll need to wipe out the human race (and quite a few animal species). I don't really think many things are beneath me, and arguing my case certainly isn't, but there are many other reasons why I am not really interested in explaining something like that in detail over the internet to random people I don't know. The Quixotic Potato (talk) 23:20, 13 May 2016 (UTC)
 * I was actually talking about your hypothetical Liehtenstein case when I mentioned Tel Aviv above. There are actually times when this question can become relatively relevant, though not so much by the Jews' doing.  For example, I was stunned to learn last year that the British Home Secretary can, pretty much on his own interpretation of a rather cryptic phrase, revoke citizenship of people who might reasonably be expected to be able to obtain citizenship elsewhere, which I assume includes Jews, and also includes residents of many Islamic states.   Now in a situation like that, where a person cannot be confident he will always have the right to be a British citizen and could be deported to some other country, he might be expected to start thinking about whether he will be safe and accepted in that country rather than Britain.  Where racism is concerned, the people here discussing didn't start that fire - it's the bureaucrats with their policies and their forms and their databases and social programs who run that show.
 * As for optimism, well, there are a lot of different issues in the world, but I remember in the 1980s it seemed like the U.S. having a black president was a pure pipe dream; but even more profound is the difference in the gay rights movement, which is usually considered to have officially started in 1969 with the Stonewall riot. In the 1980s, sodomy was still formally illegal in much of the U.S.  Followers of Lyndon LaRouche were all over the country advocating for a round-up and quarantine of people who had or might catch HIV, an epidemic very few people in government seemed to view as a bad thing.  Not one person in ten knew that there were other species that could be homosexual.  But people argued and rallied and made their point, and the situation changed.  So with things like that, I would not dismiss the usefulness of explanations and discussions. Wnt (talk) 08:05, 14 May 2016 (UTC)
 * Vaduz is the capital of Liechtenstein. London is the capital of both England and the UK. AFAIK I didn't dismiss the usefulness of explanations and discussions. Did someone "lose" or "win" this discussion? The Quixotic Potato (talk) 08:14, 14 May 2016 (UTC)
 * I lost a few minutes reading it and judging it a tie. Ten points to everyone. InedibleHulk (talk) 08:33, 14 May 2016 (UTC)
 * By "lose" I did not mean you vs. me, but you vs. racism, as I got the impression you wanted to oppose it. Wnt (talk) 09:16, 14 May 2016 (UTC)
 * I don't think I understand what you mean. How can a single potato defeat racism? Racism will still be here after I am gone, does that mean that I lose and racism wins? I do not have nuclear weapons (very few potatoes do). The Quixotic Potato (talk) 09:56, 14 May 2016 (UTC)
 * Hillary Clinton will acquire nuclear weapons next year, by appearing less racist next to someone else. And then every man, woman and child on the planet can equally identify as "terminated". Till then, the stalemate drags on. InedibleHulk (talk) 11:47, 14 May 2016 (UTC)

Doesn't pass objectivity test. Most religious people I know identify with their religion first, regardless. Even the most patriotic, such as voluntary soldiers willing to die for their country, still have "God, Country, Family" as a fundamental understanding of precedence. It's the basis by which conscientious objectors have their religious beliefs respected (i.e. Quakers in the U.S.). I'd be surprised if people choose one over the other as an identity but religious beliefs can trump duty requests to country or family. --DHeyward (talk) 02:23, 14 May 2016 (UTC)
 * I think identity and loyalty are being incorrectly conflated here. It's hard to imagine how anyone who believes in God could disagree with the proposition that loyalty to God is more important than loyalty to country.  That's a different question from whether you identify more with your compatriots or your co-religionists.  (As an individualist, I think all this "identification" stuff is way overrated anyway.  And no, I don't "identify as an individualist"; I just am one.) --Trovatore (talk) 02:36, 14 May 2016 (UTC)
 * posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)
 * Thanks for proving my point. Being a misanthropist is not the same thing as being anti-social. In my country there are non-religious burial services btw. You should read my userpage, I love real Christians like Wade Watts and I dislike hypocristians like the Westboro Batshit Church and yourself. Please judge me, and cast the first stone. I suggest you go read the bible, and then apologize. The Quixotic Potato (talk) 09:28, 15 May 2016 (UTC) p.s. It is possible that you are a troll who is trying to make Christians look bad, if so then you have achieved your goal. If not, then I have to inform you that you just made Jesus facepalm. I am an nonbeliever in religions without a god or gods, and an atheist for all theistic religions. I probably wouldn't even mind being described as an anti-theist.  The IP 151.226.217.27 does not understand your religion. Maybe you can explain it to him.
 * posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)
 * You are a hypocristian, it is a portmanteau of hypocrite and Christian. The Westboro Batshit Church is a bunch of people who do not understand the Bible, just like you. There are many nontheistic religions. No, you do not understand Gerda's religion, because she is a Christian. The Quixotic Potato (talk) 12:50, 15 May 2016 (UTC)
 * Sort of a pity that we have an article on nontheistic religions, but none on nonreligious theism. It certainly exists; I'd go so far as to say that it's a pretty popular position, at least if you take it broadly to include people who follow religious observance for social reasons, and also believe in God, but don't think that the first has much to do with the second. --Trovatore (talk) 20:07, 15 May 2016 (UTC)


 * [un-indent] This is a perfectly legitimate question, but it belongs on the Humanities (or Miscellaneous) reference desk, not here! 2601:646:8E01:515D:F88D:DE34:7772:8E5B (talk) 01:32, 17 May 2016 (UTC)

For which person is more easier to lift his hands?
For which person is more easier to lift his hands, to someone thin or for someone muscular? I think that for the thin it's more easier because for the muscular guy he needs to carry heavy muscles = more weight. But I'm not sure about that. 93.126.95.68 (talk) 09:32, 12 May 2016 (UTC)
 * But muscles are the part of the body that does the lifting. The extra weight of the muscles is cancelled out by how much more the muscles could carry.  Otherwise, no one in history would have ever tried to develop their muscles in any way, shape, or form.  Ian.thomson (talk) 09:36, 12 May 2016 (UTC)
 * The muscles that lift the hands are well away from them and it is mainly tendons that contribute to the weight. This is even more so for your fingers, most of the muscles for them are in your forearm, see arm abd Muscles of the hand. Dmcq (talk) 12:11, 12 May 2016 (UTC)

probably not an answerable question as stated...what is meant by "easy"? how much total energy is required by the movement? how the movement subjectively feels to the individual? etc etc.68.48.241.158 (talk) 14:59, 12 May 2016 (UTC)

Who's in better shape, the 180lb man or the 300lb man? Now put 120lbs of stuff on the 180lb man so they weigh the same. I'm betting the 300lb man being accustomed to the weight does better than the guy with weights added. --DHeyward (talk) 02:27, 14 May 2016 (UTC)

Exercise: Repetition vs. weight lifted.
I have decided to move to a more structured exercise program. Right now I bike, sprint or jog, swim or lift weights, etc., based on what I am in the mood for.

So I looked at a few exercise websites, and I am now totally confused about repetition vs. weight lifted. So let's assume to keep the numbers simple that I can lift 100 Lbs -- once. If I try a second time I can't make it. Pretty much everyone agrees that maximum weight and one repetition is a bad exercise program. So I switch to 1 pound, and find that I can do many, many repetitions. Still not good. My heart rate and breathing don't increase much and I quit because I get bored.

I have also noticed that top sprinters or marathon runners and top distance runners or power lifters have different kinds of muscle development. I am kind of looking for the ability to lift a heavy weight, because that fits the kind of work I tend to do; "grab the longest wrench and we have try to unstick that 2-inch OD bolt". But I don't want to totally neglect my heart and lungs either.

So let's say I reduce the weight until I can do 10 repetitions but not 11. Compare that to being able to 30 but not 31 with a lighter weight. Which will be best number of repetitions for building muscle mass? Which will be best for cardiovascular fitness? Weight loss?

Surely someone has done some scientific research on this question. Alas, doing a web search on it is like drinking out of a fire hose. --Guy Macon (talk) 10:02, 12 May 2016 (UTC)


 * There is training for strength, power, endurance and hypertrophy. All require a different combination of sets and reps. It is not only weight vs. number of repetition. There are other variables you have to keep an eye on: speed, sessions per week, rest between sessions, reaching muscle failure (or not). Take a look at this table: .Llaanngg (talk) 12:16, 12 May 2016 (UTC)


 * Interesting! In the chart, what is the difference between strength and power? --Guy Macon (talk) 12:22, 12 May 2016 (UTC)


 * Strength: how much weight your muscles can move. (important for weight lifters)
 * Power: how quickly you move a weight. (important for martial arts, javelin/discus/hammer throwing).
 * Notice the difference in appearance between a weight-lifter and a martial arts practitioner  Llaanngg (talk) 12:29, 12 May 2016 (UTC)
 * So any idea where that table came from, or a ref that might explain this distinction? I mean thanks for this good info but it doesn't really help us dig in to any further refs. My suggestion for OP is to get a nice medicine ball and read up on various techniques - Many people think they are fun and he might find the less boring than other exercises too :) Here is a general list of techniques that also contains some good looking book refs. Here  is a video specifically geared toward developing punching power by using a ball, and here's one for endurance . SemanticMantis (talk) 22:21, 12 May 2016 (UTC)
 * I think the question is a good one and I'm surprised there is not more on it. About the boring business - I must admit I just don't understand why people want to bore themselves stiff trying to get bulging muscles. There's lots of alternatives which are much more social, my main exercise is dancing which is fun and has a mental component which I think is good. Dmcq (talk) 22:57, 12 May 2016 (UTC)


 * Here's a small selection of somewhat relevant and freely accessible scientific studies on the topic:   SemanticMantis (talk) 23:06, 12 May 2016 (UTC)
 * I got into gym work and weight lifting for a while and one thing I noticed is that there are almost as many answers to this question as there are people who are training at gyms. And MOST of it is just based on personal opinion and anecdote. The general rule of thumb seems to be: the lower your "reps to fail" the more you are working on bulk and strength, the higher your reps to fail the more you are working your lean muscle and stamina. Low reps are in the range of 4-8 high reps is 10-14. If you are starting out, you can't go wrong with 3 sets of 8 reps for a while, learn a bit about which groups of muscles you should train together and which you should train separate. Once you start seeing improvement in your strength and you are increasing the weights you can lift, make an appointment with a personal trainer and have them create a training program specifically for what you want to achieve. With SO many pro atheletes, weight lifters, trainers etc, you'd think a question like Training to failure would be figured out by now, it's either better or not, but clearly so much of this topic is so complicated that even a seemingly easy question like this has a lot of room for experts to disagree. Vespine (talk) 23:09, 12 May 2016 (UTC)

If you're not looking for something too specific you're much more likely to stick to exercises you enjoy doing.Bastardsoap (talk) 16:14, 14 May 2016 (UTC)

Thread gauge T and Z for Go and No Go
"Normal" thread gauge says "Go" on one end and "No Go" on the other end, simple enough. But this set I brought says "T" on one and "Z" on the other. Which letter correspond to "Go"?

And where did the "T" and "Z" come from? I'm guessing German?

I tried googling "thread gauge t z" but queries with single letters in it are hopeless.Johnson&#38;Johnson&#38;Son (talk) 12:05, 12 May 2016 (UTC)
 * If you believe this http://www.ebay.com/itm/Metric-Thread-Ring-Gage-Gauge-Set-M12-x-1-5mm-6G-T-Z-/171427721156 T = go, Z = no go --TrogWoolley (talk) 13:01, 12 May 2016 (UTC)
 * Other sellers say the same thing  . BTW, while searching for single letters is often not productive it's not always the case and I wouldn't say it's the case here as these results were found from searching. I'm not really sure whether you meant searching for (without the single quotes) 'thread gauge t z' or '"thread gauge t z"' (i.e. including the double quotes). If you meant the later, it's not surprising that the results weren't useful. If you meant the former, the obvious problem is that many of the results either say 'tz' or don't even have the tz. In fact some of them aren't even finding 'thread gauge'. So the next logical search attempt may be 'thread gauge "t" "z"' or perhaps '"thread gauge" "t" "z"'. Both of these will probably find at least one of these results (either directly or indirectly) or similar within the first 10-20 results. Since go/no-go is believed to be the standard terminology the next obvious search is something like 'thread gauge "t" "z" go no go' or '"thread gauge" "t" "z" go no go' which doesn't actually seem to find anything much more useful although may find one of the above results in number one place (ironically not one using the go/no go terminology itself but coming from elsewhere) and perhaps a few more results earlier on depending on precisely what you're comparing with. Unfortunately neither seems to find where the symbology originates. Nil Einne (talk) 14:46, 12 May 2016 (UTC)
 * For those wondering what this thing is for, we have a Go/no go gauge article. If T/Z is a standard nomenclature, please update it. DMacks (talk) 16:47, 12 May 2016 (UTC)


 * Have updated article. For the non-metricated, is it clear enough to make sense? --Aspro (talk) 18:31, 13 May 2016 (UTC)
 * Thanks! I wordsmithed it a bit to clarify (I think:). But I do not have access the the full actual standard, so I am not sure if I am clarifying it correctly vs taking it in an incorrect direction. please check and let me know. DMacks (talk) 19:47, 13 May 2016 (UTC)


 * But following up, what is the etymology of T and Z?  → Michael J Ⓣ Ⓒ Ⓜ 23:45, 14 May 2016 (UTC)

Orbital axes
I know that every planet's orbit has a different eccentricity and inclination. What I wonder is, do the semi-major axes of the various orbits point in the same direction? Perhaps a better way of asking is, do the non-solar foci have any correlation to each other? → Michael J Ⓣ Ⓒ Ⓜ 16:20, 12 May 2016 (UTC)


 * The orientation of the semi-major axis is not fixed but undergoes apsidal precession over many thousands of years (110,000 years for Earth). Since the various planets evolve at different rates, I assume their orientation at any given time relative to each other is mostly random.  Dragons flight (talk) 16:33, 12 May 2016 (UTC)


 * While reading a magazine or similar article recently about the possible Planet Nine, I happened to notice that all (or possibly all bar one) of the planets' semi-major axes are confined within about (I think) 135° [subject to further checking] and wondered whether this might be more than chance. {The poster formerly known as 87.81.230.195} 185.74.232.130 (talk) 18:07, 12 May 2016 (UTC)
 * A range of 135 degrees over 8 planets is hardly how I would define "confined", considering that 180 degrees would be the maximum value for variance. -- Jayron 32 18:16, 12 May 2016 (UTC)


 * How is the orientation measured? By angle ±° from that of Earth?  → Michael J Ⓣ Ⓒ Ⓜ 18:32, 12 May 2016 (UTC)
 * I'm assuming it's 135 degrees from the furthest difference in axis: 90 degrees would mean the semi-major and semi-minor axes line up, and 180 degrees would mean that you're lined up again on semi-major axes. If we had them all within a small number of degrees, that would be "confined".  135 degrees seems like a fairly wide range of differences.  -- Jayron 32 18:40, 12 May 2016 (UTC)


 * While it is true that 180° difference means that they are lined up again on the semi-major axis, it does not mean that that is the same as 0° difference—actually, viewed from above with one focus to the left and the other to the right, the foci of one planet's orbit are the Sun and something to its left, and the foci of the other planet's orbit are the Sun and something to its right. They go off in opposite directions, not sharing their second foci. So viewing these as extreme opposites, a range of 135° Is only half as great (i.e., compared to 360° rather than 180°). Still a substantial variation, though. Loraof (talk) 19:52, 12 May 2016 (UTC)


 * Actually, the correlated trans-Neptunian objects' orbits depicted at Planet Nine look like they range over about 135°. Apparently that is considered to be highly correlated enough to give rise to the hypothesis. Loraof (talk) 20:21, 12 May 2016 (UTC)


 * To add a little more clarity, I was indeed taking the axes to be directional from perihelion to aphelion, so the full possible range would be 360° {The poster formerly known as 87.81.230.195} 2.122.0.142 (talk) 01:19, 13 May 2016 (UTC)


 * I've heard that the planets' longitudes of perihelia get pulled back into a wide range by Jupiter's gravity when they stray too far. Sagittarian Milky Way (talk) 20:31, 12 May 2016 (UTC)

Icarus again
What arm flipper type would need the least antigravity for an average young man to fly? Purest flight: a stationary start without needing wind, thermals, running, jumping, updrafts, denser air, rotors, machines, energy storage, lifting gases, genetic engineering, doping, magnets, high altitude, space travel, oxygen (more than usual), multiple guys tied together, shock waves, moving the ground..

Is tapered better? Square tip? Low aspect ratio or high? Longer than arm or no? Aluminum wing for the poor and carbon fiber for the rich or something else? Sports racket shaped? (how big a handle and head?) Sagittarian Milky Way (talk) 20:05, 12 May 2016 (UTC)


 * Aerospace engineering is not easy. Even the experts seem to hang around wind tunnels and stare at models under polarized light to try to figure out the best scheme.  And I don't know anything about it, which makes this tough for me to answer. :)  But I'm thinking we might separate it into some sub-questions:


 * How light and tough can a material be? If a wing held up by one arm is (for example) 10x2 meters, how much does it have to weigh to be able to support itself and rider?  I have no idea if there is a way to set a theoretical limit to that.


 * How low can the air resistance be on the upstroke, assuming the cleverest engineering? I have no idea if there is a way to set a theoretical limit to that.


 * How high can the air resistance be on the downstroke, assuming the best possible engineering to manipulate vortices and turbulence? I have no idea if there is a way to set a theoretical limit to that.


 * At this point I should vacate the floor in favor of the experts I hope to have nettled. Wnt (talk) 21:33, 12 May 2016 (UTC)
 * If you're seeking a scientific answer, it's pretty clear that there is no possible way to build a human-powered flight system that depends on flapping your arms, nor by using your own muscles to flap any contraption you can conceivably strap to your arms. The topic has been researched extensively.  Start at human-powered aircraft.  The most successful human-powered designs have been glider-like aircraft with propellers powered by the aviator's leg-muscles, using a bicycle-gear-like mechanism.
 * If you're using humans to power the aircraft, you wouldn't really want to use their arm muscles - the legs of a human can deliver more power, and power is what you need most.
 * Take a look at a small fixed-wing airplane propeller's airfoil: it's not actually very large at all, but it is attached to a powerful engine - typically an internal combustion engine. For example, my copy of the POH says that the Cessna 172 has a 75-inch diameter McCauley propeller.  Accounting for the spinner dome and the prop root, that means that the entire 2550 pound aircraft is being pulled through the air by an airfoil whose wings are less than three feet long.  The real magic technology that makes flight possible - at least, for heavy objects like humans - is power.  With enough power, you can go flying even if you've got very short, stubby, drag-inducing wings.  In fact, some people build them that way on purpose, because they're a lot of fun.
 * (I'm sure some glider pilots will have some different opinions... but our OP has specifically asked to exclude wind and thermals)...
 * As far as building materials, well... the original Bellanca Citabria was built with (mostly) wooden wings, but you can get about an extra hundred pounds of useful load if you fly out to the American Champion factory and have them perform a legal wing conversion to use an Aluminum Spar; and there are some who swear that the Carbon Cub is three hundred pounds lighter than the standard Super Cub...
 * Nimur (talk) 01:21, 13 May 2016 (UTC)


 * Without demurring from what you say, Nimur, you're ignoring SMW's stipulation of antigravity. If, for example, one was entirely supported in the air by 1 gee's-worth of antigravity (where did I put my cavorite belt?), one could obviously propel ones self to a degree with arm-operated 'wings', just as one can swim in the sea. Similar considerations would apply if one were in, say, air at 1 atmosphere of pressure in a lower or zero gravity environment. I bet it'd be bloody tiring, though. {The poster formerly known as 87.81.230.195} 2.122.0.142 (talk) 01:31, 13 May 2016 (UTC)
 * Right, human flight by flapping wings is essentially impossible on regular Earth with regular gravity, but with antigravity or even some level of lower gravity it should get much easier. In addition to lift and such, there's also the control system to think about. Wings on arms are unwieldy. OP may enjoy For_the_Birds_(short_story), which contains Asimov's solution to the problem. SemanticMantis (talk) 14:09, 13 May 2016 (UTC)

Actual number of turns
In the case of, say a step-down transformer, we know that the ratio of turns determine the ratio of ac voltage we get, respective to the input of ac voltage. Supposing that we have 100 turns at secondary coil while there are 5000 at the primary one, we get 4.4 v ac for 220 v ac. Now if we change number of turns from 100 to 1000 at secondary and to 50000 from the earlier 5000 at the primary (we may have to increase overall transformer size, of course),but we still will get 4.4 for 220, since turn-ratio is same. But it seems sure that some other overall improvement must have come in performance. What would precisely that be ? And why ? 124.253.246.178 (talk) 23:32, 12 May 2016 (UTC)
 * I think it might be efficiency: the larger the number of turns on the coil, the greater the flux linkage and therefore the greater the induced emf. . --Tagishsimon (talk) 23:46, 12 May 2016 (UTC)
 * But the induced e.m.f. depends on the turns ratio which is stated to be unchanged. . The transformer with the greater number of turns has higher mutual inductance and can therefore be used at lower ac frequencies. Core saturation will however occur at a lower primary current, which limits the maximum power handling. If increasing the number of turns was achieved by using thinner wire, the efficiency loss due to Joule heating increases. See the article Transformer. AllBestFaith (talk) 00:04, 13 May 2016 (UTC)
 * Just as a curious factoid, a tesla coil can have thousands of turns in the secondary and as few as 6 in the primary! (maybe even fewer, but I know 6 for sure.) Vespine (talk) 04:56, 13 May 2016 (UTC)
 * And the other way 'round (hundreds or thousands in the primary, vs as few as one (!) in secondary) is a common college physics demo. DMacks (talk) 05:21, 13 May 2016 (UTC)
 * By increasing ten-fold the number of turns on primary and secondary, you will indeed get the same voltage as with the former transformer under no-load conditions. The problem comes when you connect a load that draws current. Let's assume that in the former transformer, the core size and wire size were adequate for the current drawn. Increasing the number of turns ten-fold implies a much bigger core to accommodate them. That's fair enough. But the Ohmic losses in the windings will now be ten-fold too, so in order to reduce these so that the transformer puts out the same voltage as before under load, wire with greater cross-sectional area must be used, again increasing the core size. I don't see any advantage. All I see is the negative impact of a heavier, larger, and more expensive transformer that is wasteful of natural minerals such as copper and iron. Akld guy (talk) 06:50, 13 May 2016 (UTC)
 * Do you mean that savings in world resources of copper and iron are to be had just by reducing ten-fold the number of turns on primary and secondary of transformers? AllBestFaith (talk) 13:31, 13 May 2016 (UTC)
 * No, because there's a minimum core size for any transferred amount of power. The cross-sectional area of the core in square inches is the square root of V x A divided by 5.58, where V x A is the voltamps output Radiotron Designer's Handbook, p.235. So, assuming that the core size was correct initially, it cannot be made smaller. That also means that the number of turns in the primary winding cannot be reduced either, since the flux density would fall, severely reducing the output voltage under load. Akld guy (talk) 01:21, 14 May 2016 (UTC)
 * No, a minimum core size for a power transformer in Eurasia using 50 Hz can be reduced slightly (hardly significant in commerce) for use in the Americas at 60 Hz, be reduced markedly for an aeronautic 400 Hz power system, and be reduced much more (with a change of material) in a SMPS. The figure you quote is an empirical guide that, to guess from the source, is just for 50/60 Hz transformer cores. AllBestFaith (talk) 15:14, 14 May 2016 (UTC)
 * The comparison was one transformer configuration versus another. Nobody said anything about forcing a change to the frequency supplied by the electricity network so as to make the second transformer work better. Akld guy (talk) 21:18, 14 May 2016 (UTC)