The metric system sucks
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From: Andrew Usher on 5 Feb 2010 21:11 On Feb 5, 8:16 am, jmfbahciv <jmfbahciv(a)aol> wrote: > > True. And anywhere that multiplication or division is required, mixed > > units will not be used as they become too difficult. > > Now learn about dimensional analysis. Everybody has to deal with > mixed units. Mixed units = feet and inches, pounds and ounces, etc. Nothing to do with dimensional analysis. Andrew Usher
From: Andrew Usher on 5 Feb 2010 21:15 On Feb 4, 9:22 pm, Michael Press <rub...(a)pacbell.net> wrote: > The USA gallon aka Queen Anne gallon aka wine gallon > started life as a cylinder 7 inch in diameter by 6 inch high. > So why is it exactly 231 inch^3? Take the approximation pi = 22/7 and you'll get it! Of course, the only gallon that ought to be used anymore is the imperial, ~277.42 cubic inches. > A mile is a thousand double paces. One can still pace out long distances, like the Romans did, and 1,000 paces = 1 mile is pretty close. Andrew Usher
From: Marshall on 5 Feb 2010 21:21 On Feb 5, 5:58 pm, Andrew Usher <k_over_hb...(a)yahoo.com> wrote: > On Feb 5, 5:15 pm, "Bob Myers" <nospample...(a)address.invalid> wrote: > > > (1) It's inefficient (and has a higher risk of error) to > > have to deal with two systems, which we effectively > > are doing now despite being a supposedly "English > > system" country. > > As I and Bart have said repeatedly, the same could be said of > languages, in some respects more so. Yet the same leftists who want so > badly for us to go metric are pushing linguistic diversity on us. So you are saying that if there is an argument for position X, and an identical argument for position Y, and there exists a person who advocates position X but advocates against position Y, then position X is invalid. Please confirm. Marshall
From: Andrew Usher on 5 Feb 2010 21:29 On Feb 4, 9:20 pm, Mark Borgerson <mborger...(a)comcast.net> wrote: > > Well, yes, technically. But if you used a weight measured with a scale > > (any type) the correction does come into account. > > That's not necessarily true either. If you are weighing iron > cannonballs on a balance scale using iron weights, no correction > is necessary. The same holds true on a balance scale whenever > the item and weights are of equal density. If the weights are > properly calibrated for their mass in vacuo, you will get > the proper in-vacuo weight of the cannonball. Yes, but balances are almost obsolete. When measuring force as modern scales do, the full correction is needed. > > > > Of > > > > course it changes with temperature as well; it's rather fortunate that > > > > water has a much lower thermal expansion than any other liquid at > > > > normal temperatures. > > Except for mercury, of course. Mercury has a coefficient of thermal > expansion of 18e-5, while water is 21e-5. Given that low coefficient > I suppose that mercury was used in thermometers, not because it > was the best expansion medium, but because of low vapor pressures > and high visibility. More so, actually, because the expansion of mercury (like most metals) is very uniform with temperature, so that thermometers could be divided on a linear scale and be fairly accurate. Also the very wide temperature range - mercury freezes only at -38 F, and does not decompose at the highest temperatures. Finally the thermal expansion of mercury is much lower than that of organic liquids, and the stem correction is proportional to it. The thermal expansion of water, on the other hand, goes from -5e-5 at freezing to 44e-5 at boiling (per degree F). > > > (unless, of course, you go below 32F! ;-) > > > No. That's negative thermal expansion! > > Not really---ice has a coefficient of thermal expansion quite different > from the volume change with the phase change. When you cool water to make ice, it expands. That's the reverse of normal, and so can be called negative, I would say. Yes, ice itself has a positive expansion. Andrew Usher
From: Andrew Usher on 5 Feb 2010 21:35
On Feb 4, 8:11 pm, Bill Owen <w...(a)jpl.nasa.gov> wrote: > > Actually, I've long thought decimal time wouldn't be a bad idea. But > > on the other hand, the fact that everyone works with the different > > units of time shows that non-decimal units are not really confusing to > > common people, unlike what metric propaganda says. (And if they were > > consistent, they would decimalise time - and angle, which is still > > worse, as I explained in Section V of my essay.) > > This was in fact tried (for time, for a time) during the French Revolution: > > http://en.wikipedia.org/wiki/French_Republican_Calendar > > http://en.wikipedia.org/wiki/Decimal_time Well decimalising the calendar (units larger than a day) is silly, because the year is not a round number of days and can't be. But decimalising the clock (units shorter than a day) is sound. I've thought we could have 1000 minutes in a day, and no other units. 25 and 50 minutes would essentially replace the half hour and hour for measuring the duration of things. Very short times could be either decimals of a minute, or in (old) seconds which would have to be retained anyway for science. > The closest they've come to decimalizing angles is the "grad," which is > 1/100 of a right angle. That is the most natural decimalisation, I think. Andrew Usher |