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From: Bob Myers on 9 Feb 2010 16:35 Darwin123 wrote: > How about removing all regulations concerning units and see what > individuals and companies would do? That's the most sensible solution I've seen here yet - which, of course, is why it will probably never happen! Bob M.
From: Mark Borgerson on 9 Feb 2010 17:53 In article <c51f54e7-e26e-4fba-a9ec-459fdbc1e886 @j31g2000yqa.googlegroups.com>, drosen0000(a)yahoo.com says... > On Feb 9, 6:11 am, Andrew Usher <k_over_hb...(a)yahoo.com> wrote: > > On Feb 8, 10:12 am, Robin <b.ro...(a)neurol.org> wrote: > > > > > China, Europe, Russia, South America, Japan speak metric.. > > > Where do you want to sell "inched machines" or inched materials? > > > > It's not likely that they should care what units their machines are > > made to; or if they do, it's only because of laws or standards > > organisations or other bureaucratic nonsense demanding metric. > > > > Andrew Usher > > This is not true. Just look at the little matter of nuts and > threads. Metric system nutss do not fit in English system treads, nor > do English system screws fit in metric system threads. There is no > "computerization" that can make an English nut fit into a metric > thread. > The reason is not arbitrary regulations. The reason that the > translation factors from English to metric contain more than two > significant figures. However, the practice has been to set measurement > standards in units of only one or two significant figures. Once a nut > is made, or a thread tapped, there is no computerization involved. > It is also complicated that in the English system, the division of > length below one inch are divided by powers of two. The divisions in > the metric system are divided in powers of 10. Therefore, when one > translation from metric to English isn't enough. That's not entirely true. I design a lot of PC boards where the inches are divided in to mils or smaller ---- units of 1/1000 or even 1/10,000 inch. Those units are common for a lot of machining operations also. > Think of optical breadboards. It is natural for a European > machine shop to drill holes 3 cm apart, just as it is natural for an > American machine shop to drill holes only 1 inch apart. It is easier > to read the integer markings than the little divisions in between. > However, 1 inch is 2.54... cm. Breadboard applications may need > agreement between three and four significant figures. > The important thing is that this compatibility is not due to > regulations. It is due to the nature of shop work.Furthermore, > division into millimeters is not the same as divisions into 1/16 of an > inch. So when one makes markings between the "1 inch" holes, one can't > even use the same ruler. One needs both types of rulers, and lots of > arithmetic, to make smaller divisions. I don't think you should be using a ruler when measuring an optical breadboard! Almost all calipers---both digital and mechanical dial, give you results in tenths, hundredths, and thousandths of an inch. > This is an engineering problem, not a regulation problem. There is > real science and real shop issues involved that have nothing to do > with "regulation" or "government." There are arguments for keeping the > English system, but they have nothing to do with "liberals." > American regulations are what keep the English system in place. If > there was no English standardization in government regulations, > individual companies would do what they want. Some places would make > the change, and screw the American consumer. There is nothing more > communist about a "metric system" regulation than a "English system" > regulation. A government regulation is a government regulation. Right > now, Americans effectively need two sets of regulations: One for > metric and one for English. > I think the most important argument for keeping the English system > is that we already have stockpiled loads and loads of English system > parts. I do not look forward to a transition from English to metric > for this reason. Although the English is clumsy, the transition may > not be worth the price. > I suspect the bigger American companies would love to have > America changed to the metric system. I suspect that there are a lot > of "conservatives" who if not for it, are not against it either. This > is not a left versus right issue. > How about removing all regulations concerning units and see what > individuals and companies would do? > Mark Borgerson
From: Michael Press on 9 Feb 2010 20:02 In article <joo1n55f1f4is2notocvi6elvku27ar5q9(a)4ax.com>, Matt <30days(a)net.net> wrote: > A (aqueous) chemistry lab is a cherry-picked environment for arguing > the merits of the metric system. The density of water is quite > important there. Not so much in a metallurgy lab. The density of iron > is expressed no more conveniently in metric (7.874 g/cm^3) than > English units (491.6 lb/ft^3). Everyone knows that only SI units are proper so that should be 7874 kg/m^3'. Convenience has nothing to do with it. We must sacrifice our comfort. -- Michael Press
From: Andrew Usher on 9 Feb 2010 22:40 On Feb 9, 7:58 am, nos...(a)nospam.com (Paul Ciszek) wrote: > >The Gaussian units, of course. It's not the precise values of the > >units that are special, but the fact that they are physically correct > >(e.g. in measuring E, B, D, H in the same unit) and SI is not. > > One more time: Can you conveniently use Gaussian units for circuit > design? Since you got the formula for a simple time constant wrong, > I am doubtful that you can use any units for circuit design. The only reason that using them for circuit design would be less convenient is that components are made to SI units. I have no problem with SI being used for circuit design - indeed it proves my point about established units - only with assertions that SI is the superior system for electromagnetism, which is clearly false. Andrew Usher
From: Andrew Usher on 9 Feb 2010 22:45
On Feb 9, 8:56 am, "Mike Dworetsky" <platinum...(a)pants.btinternet.com> wrote: > Cup sizes are not metric, though the 38 translates to size 85 cm. So the > EU/world size would be 85D. However, many countries have their own scales > for bra sizes, including some European countries that are otherwise metric. Ring, I forgot about the 4.5 inch difference in band size. Cup sizes aren't really English either, though they pretend to be. It's best to think of them as arbitrary. Andrew Usher |