Wikipedia:Reference desk/Archives/Miscellaneous/2010 May 21

= May 21 =

Tesla Motors
Where are Tesla Motors cars manufactured? Everard Proudfoot (talk) 01:15, 21 May 2010 (UTC)
 * Model S sedan
 * Roadster - final assemby chassis
 * electric Powertrain 77.86.115.45 (talk) 01:41, 21 May 2010 (UTC)

Crab Lice
Why can't animals get crab lice (also known as pubic lice)? - I need to know for a school project! ~Qwerp Qwertus  |_Talk_| |_Contribs_| 04:30, 21 May 2010 (UTC)
 * We have an article on the buggers: Crab louse. It confirms that humans are the only known host, but does not say why (and that particular assertion is not supported by an inline citation).  I've also left a message on the talk page to see if there are any experts on the critters over there. Buddy431 (talk) 04:49, 21 May 2010 (UTC)
 * As an ancillary point – and assuming that our article's note about species specificity is correct – one wonders if there are not other, related lice which occupy similar niches in other mammals. TenOfAllTrades(talk) 11:57, 21 May 2010 (UTC)
 * Thanks! I know that there they have counterparts in some other mammals - like gorillas, maybe it's just because they are different enough to be another species. ~Qwerp Qwertus  |_Talk_| |_Contribs_| 13:37, 21 May 2010 (UTC)
 * Presumably it must have been quite difficult for those living on different animals to interbreed, so they may well over many generations have drifted apart.148.197.114.158 (talk) 15:27, 21 May 2010 (UTC) though that still doesn't answer the question of why the animals can't catch them from humans. Perhaps they can, but just rarely do?148.197.114.158 (talk) 15:28, 21 May 2010 (UTC)
 * Given that crab lice are predominantly spread by sexual contact, and making the (hopefully reasonable) assumption that inter-species sexual contact is sufficiently rare there may have been allopatric speciation involved. This is just an informed guess on my part, I have no evidence one way or the other. 131.111.185.68 (talk) 17:28, 21 May 2010 (UTC)


 * sufficiently rare--excludes large areas of Somerset on a lonely weekend... Lemon martini (talk) 11:01, 22 May 2010 (UTC)

Historical Centuries and Decades
Hello:

I was unaware that decade boundaries overlap century boundaries. Example: Wikipedia defines the Tenth Century in the Julian Calendar in the Common Era as being from 901 to 1000. I agree. However, the same source discusses that century's first decade as being from 900 to 909. Shouldn't the first decade of ANY century begin at the first year of that century? E.g., first decade XX01-XX10, second decade XX11-XX20, third decade XX21-XX30. . . LAST decade XX91-XX00.

In the Tenth Century, this logic would dictate first decade 901-910, second decade 911-920, third decade 921-930. . . LAST decade 991-1000. At the present time in 2010, we would be ENDING the first decade of the 21st Century and beginning the second decade in 2011. —Preceding unsigned comment added by Dick1945 (talk • contribs) 05:24, 21 May 2010 (UTC)


 * Yes, your logic is sound, but, unfortunately, logic and common usage don't coincide. Most people assume (wrongly) that there was a year zero, so they take January 1st 2010 as the start of a new decade, just as they celebrated the millennium on January 1st 2000. Then we could start arguing over whether the Common Era really began in 4 BC, so I celebrated the millennium at the start of 1996.    D b f i r s   07:22, 21 May 2010 (UTC)


 * (e/c)Yes. Because there was no year "zero" all decades and centuries should logically start with "1". (Of course there was no year 1 either, but that's beside the point.) However, most people are not as pedantic as us, and prefer the equally logical view that all the 'seventies, say, start with 197x and so on.--Shantavira|feed me 07:30, 21 May 2010 (UTC)


 * I would very much like to see a citation about most people assuming there was a year 0. In my view, most people would assume no such thing, because it makes no sense to start counting anything at all, whether it be years of a new era, pages of a book, fingers on your left hand, days of the month, or Mother Courage's children, with a zero.  They're all assumed to start with 1, unless we're told otherwise in some particular case.  People group decades in a certain way for common convenience.  It's intuitively obvious that "the 1940s" are the years 1940-1949, for example, so this needs no explanation.  But if they're talking about "the 5th decade" of the 20th Century, that's 1941-1950.  These are equally valid ways of grouping years into decades, as long as you don't confuse them.  --   Jack of Oz    ... speak! ...   08:34, 21 May 2010 (UTC)
 * The same goes for centuries as well. If I said "the fifteen hundreds", I would be talking about the years 1500-1599, which is slightly different than "the sixteenth century", 1501-1600.  But while both constructions for specifying centuries are used, nearly everyone refers to decades as "the twenties" rather than "the third decade" or "the one-hundred and ninety-third decade". Buddy431 (talk) 12:27, 21 May 2010 (UTC)


 * The difficulty is that people tend to think of 'BC' dates as negative numbers and 'AD' dates as positive numbers. Which would lead you to believe that the years -3 to +3 went: 3BC, 2BC, 1BC, 0, 1AD, 2AD, 3AD.  But that's not how historians do it.  There was no year zero. Hence, 2000 years of AD-ness ended in 2001, not 2000.  But people are obsessed with round numbers and base-10 arithmetic.  Jan 1st 2000 would have been just another boring day if we had 12 fingers - or if the earth's orbit was just a little bit longer - or if people revered numbers ending in '7' instead of '0' or if the christian tradition had decided to pick a different poor schmuck to be "the son of God", or if some nation other than the British had found the best way to calculate latitude and chose where the zero meridian should be!  But it would still have been cause for great excitement whether the historians had thought more carefully about 'year zero' or not.   Since the system is already totally arbitrary and people-mindset-centered, we might as well label millennia, centuries and decades according to how most people think they should be labeled rather than trying to get all scientific/mathematical about it.  Hence, it's worthless to wonder "why" - that's just how it is.  SteveBaker (talk) 13:20, 21 May 2010 (UTC)
 * That decimal obsession is how we got stuck with the Metric System. :) However, the first millennium ended "in" 2000, not 2001; i.e. on December 31, 2000, not December 31, 2001. Years 1 through 2000 are two thousand years. ←Baseball Bugs What's up, Doc? carrots→ 21:52, 21 May 2010 (UTC)


 * Maybe you just have to "come to terms" with it in your own way:
 * Every decade goes from xxx0 to xxx9 -- EXCEPT the first one.
 * Every century goes from xx00 to xx99 -- EXCEPT the first one.
 * Every millenium goes from x000 to x000 -- EXCEPT the first one.
 * Solves the problem rather neatly, for me! DaHorsesMouth (talk) 01:26, 22 May 2010 (UTC)


 * Speaking as a member of the group of most people, this is my feeling on the matter as well. Except the last instance should be x000 to x999, was that a typo? 81.131.7.15 (talk) 09:11, 22 May 2010 (UTC)


 * Not only was there not a year 0, there was also no year 1, 100, or even 501, so really when people started counting the years such, they could start wherever they wanted, and 0-9 seemed to make sense. Just to confuse things a bit more, the date of the new year has been moved a few times as well, I have seen it recorded as being in December, January, March, June and possibly May, if I remember correctly. Then there is the question of leapyears, the date on January 1st 2000 was quite a few hours out, and that is before we get on to the problems of months, equinoxes, easter, lunar calendars and the start and end of each day. Finding the date is a very complicated business, I for one appreciate any attempt to make it a little easier. 148.197.114.158 (talk) 09:35, 22 May 2010 (UTC)
 * Or, if you don't like the system, you can always create a new calendar or your own, and that can do anything you want. 148.197.114.158 (talk) 09:47, 22 May 2010 (UTC)

Equivalent of B.A.M.S. Degree of Panjab University with B.A.
I want to know whether Degree of B.A.M.S. (Bachelor in Ayurvedic Medicine & Surgery) awarded by Panjab University is considered equivalent to B.A. or not.

Dr Jyoti Bala —Preceding unsigned comment added by 210.56.110.84 (talk) 08:52, 21 May 2010 (UTC)


 * In what country, and for what purpose? TenOfAllTrades(talk) 11:55, 21 May 2010 (UTC)


 * I doubt it, but it depends what you mean by "equivalent". That subject would not normally be classed under "Arts". See Bachelor of Arts.--Shantavira|feed me 13:35, 21 May 2010 (UTC)

Bend test
Pls. Clarify 0t,1t 2t bend test. Need of this test in reference to galvanized/colour coated coils. —Preceding unsigned comment added by Rakeshknit (talk • contribs) 11:36, 21 May 2010 (UTC)
 * What? ╟─ Treasury Tag ►  consulate  ─╢ 11:39, 21 May 2010 (UTC)


 * This appears to be a follow-up to an archived question; see Reference_desk/Archives/Miscellaneous/2010_May_10. I'm not sure how much more help we can provide, beyond the links given in response to that question.  -- Coneslayer (talk) 12:32, 21 May 2010 (UTC)


 * I'll repeat the link here for ease of finding:
 * Answer  77.86.115.45 (talk) 12:57, 21 May 2010 (UTC)
 * That text is a bit confusing. this is a bit more clear.LeadSongDog come howl!  05:58, 22 May 2010 (UTC)

I'm looking for a pseudonym that has the name "Butch"
I suppose when people here the word "butch" they might think lesbians, or tough guys like Bruce Willis's character "Butch Coolidge" in Pulp Fiction (here). I tend to think of Butch Vig (as in here). (I've also thought "Butch Diamond"). I'm not intending it for internet purposes, but rather for snailmail, so it should resemble a real name to an extent. Additional note, I'm a male het. Any suggestions? Thanks.205.189.194.208 (talk) 15:24, 21 May 2010 (UTC)


 * I'm not sure what your question is, but Butch is a real name. It's short for butcher of course. Why not call yourself Butch if you want to? If you're looking for a word to go with it, only you can decide that. Butch the Bulldog has a nice ring to it.--Shantavira|feed me 17:16, 21 May 2010 (UTC)


 * I've known folks named "Butch", and I'm fairly certain there have been public figures with that name. Butch Wynegar and Butch Buchholz come to mind right off the bat. ←Baseball Bugs What's up, Doc? carrots→ 21:44, 21 May 2010 (UTC)
 * If you search under "Butch", there are a number of notable figures with that nickname. I do NOT recommend adopting any of their last names for your use. And probably not an obviously fake name like "Butch N. Femme", either. Maybe some white-bread name like "Robertson", or whatever. ←Baseball Bugs What's up, Doc? carrots→ 21:48, 21 May 2010 (UTC)


 * "Butch Cassidy" actually is a pseudonym! — Michael J  22:22, 21 May 2010 (UTC)
 * Homer Simpson used the macho name Max Power, so I recommend Butch Power. Deor (talk) 02:26, 22 May 2010 (UTC)
 * Ones that occur to me as sounding good: Butch Majors, Butch Willis, Butch Abrams.

Infinity
If you sit at the top of a bottomless pit and lower an endless rope down into it, how much rope can you lower into the pit?

148.197.114.158 (talk) 15:34, 21 May 2010 (UTC)
 * Any amount you want to. ←Baseball Bugs What's up, Doc? carrots→ 15:42, 21 May 2010 (UTC)


 * Let D be the depth of your bottomless pit. Let L be the length of your endless rope.  If D−L≥0 then all the rope will fit without lying on the pit's nonexistent bottom (assuming that's what you want).  If D−L<0, then the answer is D.  Ka renjc 16:00, 21 May 2010 (UTC)


 * Hold on thar, Baba Looey. Infinity is not a number it's a concept of expansion without bounds. Both "infinities" would be the same "size", i.e. boundless. You could lower 1 foot, or 1 mile, or 1 parsec of rope into the pit, and you would be no closer to finishing off the rope than you were before you started lowering the rope. ←Baseball Bugs What's up, Doc? carrots→ 16:04, 21 May 2010 (UTC)


 * Infinity is so a number! Or, well, it's several numbers. Marnanel (talk) 02:42, 22 May 2010 (UTC)
 * Infinity can be thought of as kind of the "inverse" of 0, in that some of the properties are complementary. That is, if you multiply 0 by anything, you get 0 back; and if you divide 0 by anything, you get 0 back (except 0 itself, as division by 0 is undefined). Similarly, if you multiply infinity by anything, you get infinity back, unless you try and multiply it by 0, which doesn't really work. ←Baseball Bugs What's up, Doc? carrots→ 03:04, 22 May 2010 (UTC)
 * Well apparently you can have different sized infinities. Indigestible, isn't it. 81.131.7.15 (talk) 09:22, 22 May 2010 (UTC)
 * Mathematically speaking, yes. Physically speaking, no. The only way I can think of for this to work would be if the rope going into the black hole were somehow then being spun out through a wormhole and closing back in on itself. But that's no longer an "infinite" rope, it's simply a very large loop. ←Baseball Bugs What's up, Doc? carrots→ 11:16, 22 May 2010 (UTC)
 * The core problem is that the universe, as far as we know, has a finite amount of mass/energy. As far as we know, it's a "closed system", albeit a really big one, but not infinite. So while a black hole could metaphorically be a "bottomless pit", it's not really bottomless, it just acts like one. And it's not possible to have an infinitely long rope, because it would require an infinite amount of substance, which the universe does not have. (Maybe a physics expert could jump in here and explain if there's some theoretical possibility that it could work.) The OP's premise is kind of a cousin to the old riddle about an irresistable force heading for an immovable object. The answer to that riddle is that it's self-contradictory, because both entities could not possibly exist in the same universe. ←Baseball Bugs What's up, Doc? carrots→ 11:23, 22 May 2010 (UTC)
 * Actually, to the best of my knowledge, the question of whether the total mass contained in the whole universe is finite or infinite, remains entirely open. A lot of work has suggested lower bounds, but as far as I know there are no upper bounds, and no refutation of the possibility that the universe is actually infinite.
 * However there are indeed bounds to the mass/energy contained in the observable universe. Any mass past that horizon cannot, in any way that we know of, be transported here to make up part of the rope (roughly speaking, because universal expansion means that objects past the horizon are receding from us faster than the speed of light, and there is no way to make up that deficit). --Trovatore (talk) 23:57, 23 May 2010 (UTC)
 * Actually, you know what, I'm not so sure about the "bounds on the observable universe" part. We know that the observable universe is finite, in the sense that the particle horizon, the collection of things that could in principle have produced a signal that could have reached us by now, is only a finite distance away.
 * But to get the bit about never being able to get the rope here, you need to look at the event horizon instead. It's not immediately clear to me whether the event horizon has to be only finitely far away.  Maybe BenRG or someone can clarify. --Trovatore (talk) 18:20, 24 May 2010 (UTC)
 * Depends on the tensile strength of the rope. At some point, it's going to break under its own weight. Warofdreams talk 16:07, 21 May 2010 (UTC)
 * Since an infinite rope and an infinite pit are imaginary, let's also imagine that the rope is weightless. ←Baseball Bugs What's up, Doc? carrots→ 16:22, 21 May 2010 (UTC)
 * Why? That would change the problem. Warofdreams talk 15:58, 22 May 2010 (UTC)
 * You're going to have trouble lowering a weightless rope anyway - it'll just kinda float there in a big clump. This is a silly question anyway.  I don't believe our OP really cares about the answer. SteveBaker (talk) 15:20, 24 May 2010 (UTC)


 * Would there be any gravity under the rope if the pit is bottomless?148.197.115.54 (talk) 17:44, 21 May 2010 (UTC)
 * Then you're pushing rope, so the answer is "not much". --Sean 17:50, 21 May 2010 (UTC)
 * Uh, Bugs nailed this question, not quite sure why we need to add mathematical forumlae and the like... Vranak (talk) 18:08, 21 May 2010 (UTC)


 * If you are interested in what happens when you try to place an infinite amount of something into an infinite space, Hilbert's Hotel is worth reading about. -- 140.142.20.229 (talk) 20:07, 21 May 2010 (UTC)
 * It occurs to me that the so-called "bottomless pit" could equate to a black hole. And if you have an infinitely long rope, then at the very least you're going to end up feeding the entire universe into that black hole. You might get a big bang out of that, eh? ←Baseball Bugs What's up, Doc? carrots→ 20:16, 21 May 2010 (UTC)
 * More like a big whoop.--WaltCip (talk) 05:19, 22 May 2010 (UTC)

Elevators in skyscrapers
I want a skyscraper in which any path between two different floors involves only one elevator (i.e. any two floors have at least one elevator in common). --84.61.146.104 (talk) 16:08, 21 May 2010 (UTC)
 * And where would you like it delivered? To clarify, are you looking for the name/location of the tallest building where there is an elevator that stops at every floor? Dismas |(talk) 16:10, 21 May 2010 (UTC)
 * The most staightforward approach would be to have one elevator which stops at every floor, although it would be slow and might get pretty crowded. Perhaps a paternoster lift? Warofdreams talk 16:11, 21 May 2010 (UTC)

Why aren't there any paternosters in the United States? --84.61.146.104 (talk) 16:12, 21 May 2010 (UTC)
 * Who says there aren't any?
 * I don't believe there are any. George R. Strakosch's gripping Vertical transportation: elevators and escalators, from 1967, states that the installation of paternosters is not allowed in the United States.  But it doesn't explain why, other than saying "its use demands agility". Warofdreams talk 15:58, 22 May 2010 (UTC)
 * It also requires that the elevator shaft be open to the rest of the building at every floor, which could be a fire hazard. I think that's why. 67.170.215.166 (talk) 03:26, 23 May 2010 (UTC)
 * I have seen something that looks like a bargain-basement paternoster lift at a parking garage in the District of Columbia. It was reserved for the garage's employees; attendants take your key, give you a receipt, park your car, and retrieve it for you on your return.  This manlift (an industry term, like belt manlift) was the fastest way for the attendant to travel to another floor to retrieve your car.  See also aerial lift.  --- 03:21, 25 May 2010 (UTC)

Why have most skyscrapers pairs of floors which have no elevator bank in common? --84.61.146.104 (talk) 16:17, 21 May 2010 (UTC)
 * If true it's probably to distribute the traffic. ←Baseball Bugs What's up, Doc? carrots→ 16:23, 21 May 2010 (UTC)

Because elevator design is not about linking floors by one single elevator/bank but about design a service that can facilitate the movement of the most amount of journeys most efficiently. A single elevator going from floor 1 - 100 can only service 1 request at a time, 2 elevators (1 from 1-50, 1 from 50-100) can service 2 calls more rapidly but at the expense of those going from 1-50+ (or those going from inbetween floors) having to switch elevators on the way. The question would become a case of studying how elevators are used and designing a system that works best based on expected average usage. ny156uk (talk) 16:26, 21 May 2010 (UTC)

also... This Architecture Weekly article may be of interest to you (http://www.architectureweek.com/2002/0612/building_1-2.html) ny156uk (talk) 16:26, 21 May 2010 (UTC)

Why have some skyscrapers pairs of floors which have no directly reachable floor in common? --84.61.146.104 (talk) 16:36, 21 May 2010 (UTC)


 * If you re-read my comment above this can easily be explained as...design. The elevator designer in some buildings will have decided that some floors not being directly reachable is a reasonable trade-off in terms of improvements elsewhere (e.g. faster response times for the most common journeys etc.). ny156uk (talk) 16:47, 21 May 2010 (UTC)

Are there any skyscrapers with a split-level configuration? --84.61.146.104 (talk) 16:37, 21 May 2010 (UTC)


 * A number of double-deck elevators stop at every floor, sort of.--Shantavira|feed me 17:22, 21 May 2010 (UTC)

Are there any skyscrapers with a split-level configuration, as in parking garages? --84.61.146.104 (talk) 17:25, 21 May 2010 (UTC)
 * Do you mean where part of the building is like half a story "off" from the other part of the building? ←Baseball Bugs What's up, Doc? carrots→ 20:18, 21 May 2010 (UTC)

How many elevators with at most 13 stops are needed to have a direct connection from any of the 42 floors to any other floor? --84.61.146.104 (talk) 20:17, 21 May 2010 (UTC)


 * I have a solution with 45 elevators. I have no math proof that this solution is optimal.  Comet Tuttle (talk) 20:38, 21 May 2010 (UTC)
 * The least amount of elevators needed is 4, but with the stop limitation, they wouldnt be direct, one would need to exit at a lobby or mezzazine (is that the right term? like a lobby but on a higher floor) to transfer elevators. Plus, if you stretched the elevators to go 13 floors at a time, you would have one bank that went up and down only six floors. 206.252.74.48 (talk) 20:50, 21 May 2010 (UTC)
 * I always called those skylobbies, like in SimTower. 99.241.68.194 (talk) 02:16, 24 May 2010 (UTC)
 * The article on Empire State Building says it has a total of 73 elevators. Presumably it was set up with some optimal efficiency in mind. The typical elevator rider doesn't want to go to every floor in the building, but probably only one. The exception would be maintenance crew, which is why they have something like 9 of those 73 allocated to themselves-only. But in their case, speed would not be important, as they would be going floor-by-floor methodically. ←Baseball Bugs What's up, Doc? carrots→ 20:55, 21 May 2010 (UTC)

This doesn't quite answer the OP's growing list of questions, but the approach to elevator design at Watterson Towers might be of some interest. ←Baseball Bugs What's up, Doc? carrots→ 20:22, 21 May 2010 (UTC)

Which building has the most wheelchair-inaccessible floors? --84.61.146.104 (talk) 07:34, 22 May 2010 (UTC)
 * Alan King used to tell a joke about a shopper who would buy her groceries one item at a time and slip between customers in the queueu saying, "I only have this one item". Similarly, I'm wondering if you're just really curious and that one question leads to another? Or whether you're writing a book on the subject, asking one question at a time? :) More to the point, have you tried looking for any of this info on Google? Just google [skyscraper elevator] or something like this, and you're liable to get a gazillion references, some of which might tell you anything you're looking for. ←Baseball Bugs What's up, Doc? carrots→ 11:12, 22 May 2010 (UTC)
 * I don't know about now, but Kowloon Walled City must have been a good contender. Warofdreams talk 16:05, 22 May 2010 (UTC)

Making a whistle from White Deadnettle
I came upon a reference to making whistles from the hollow stem of white deadnettle but can find no instructions as to how to go about this. Can you help? 95.149.39.70 (talk) 20:20, 21 May 2010 (UTC)
 * The .pdf document here (p.19) simply says "Children can make whistles from the square stems by hollowing out the middle."  This says: "The corners of the hollow stems are strengthened by specially strong columns of fibres. In the country, boys often cut the stems and make whistles out of them."  Any help?  Ghmyrtle (talk) 21:03, 21 May 2010 (UTC)
 * From memory, the pith in the middle of a deadnettle stem is quite soft and could be easily poked out (with a stick or piece of wire perhaps?). A better-known alternative is elder; instructions here. Alansplodge (talk) 22:06, 21 May 2010 (UTC)
 * After removing the pith, one could use one's penknife to cut a labium lip ("C" in this image) in the stem to make a one-note "flute", as shown in the link provided by Alansplodge above. Poking holes in the stem judiciously, I believe, would allow one to produce other tones. Deor (talk) 23:01, 21 May 2010 (UTC)

And for once I thought this would be an RD answer that didn't involve taking the pith out of thomething :) Lemon martini (talk) 11:03, 22 May 2010 (UTC)