The metric system sucks
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From: Andrew Usher on 4 Feb 2010 20:59 On Feb 4, 4:16 pm, Mark Borgerson <mborger...(a)comcast.net> wrote: > > I can't believe he couldn't tell you. The density of water (I know in > > my head) is about 62.4 pounds per cubic foot; 62.3 if correcting for > > the bouyancy of air (a detail the metric-philes always omit!). > > If you're really talking about density, (mass per unit volume) the > buoyancy of air has nothing to do with the result. Well, yes, technically. But if you used a weight measured with a scale (any type) the correction does come into account. > If you're talking > about the WEIGHT of a unit volume, then, in some cases, you > may need to correct for the buoyancy of air---which is, of course, > a function of altitude. Yes, if you need to be exact. But an adequate approximation for almost all purposes in most of the inhabited world is that the density of air is 1/800 that of water or 0.08 pounds/cu ft. > > 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. > > (unless, of course, you go below 32F! ;-) No. That's negative thermal expansion! Andrew Usher
From: Gerry Myerson on 4 Feb 2010 20:59 In article <f7jmm5trftkja8ikb1r2lcu6gmthcptdpg(a)4ax.com>, Antares 531 <gordonlrDELETE(a)swbell.net> wrote: > On Fri, 05 Feb 2010 09:09:55 +1100, Gerry Myerson > <gerry(a)maths.mq.edi.ai.i2u4email> wrote: > > >In article <hkeig101lnd(a)news3.newsguy.com>, jmfbahciv <jmfbahciv(a)aol> > >wrote: > > > >> I grew up in the US and cannot think in metric terms so I > >> always have to do a conversion to make guesstimates. > >> For some strange reason, kilometers seem to take "longer" > >> to drive than miles when I drove from Buffalo to Port > >> Huron, Michigan. :-) > > > >Probably because of those metric Canadian hours, what with > >each one being 100 minutes long. > > > When are they likely to change over to a metric week of 10 days? I believe that idea was tried and found wanting in the earliest days of the metric system in Revolutionary France. -- Gerry Myerson (gerry(a)maths.mq.edi.ai) (i -> u for email)
From: Gerry Myerson on 4 Feb 2010 21:02 In article <g%Han.64606$PH1.48405(a)edtnps82>, "Heidi Graw" <hgraw(a)telus.net> wrote: > >"Gerry Myerson" <gerry(a)maths.mq.edi.ai.i2u4email> wrote in message > >news:gerry-31BCD8.09095505022010(a)news.eternal-september.org... > >> In article <hkeig101lnd(a)news3.newsguy.com>, jmfbahciv <jmfbahciv(a)aol> > >> wrote: > > > >> I grew up in the US and cannot think in metric terms so I > >> always have to do a conversion to make guesstimates. > >> For some strange reason, kilometers seem to take "longer" > >> to drive than miles when I drove from Buffalo to Port > >> Huron, Michigan. :-) > > > Gerry wrote: > > Probably because of those metric Canadian hours, what with > > each one being 100 minutes long. > > What about measuring time in degrees? How might that work? > Ie. it's 360 o'clock, or 180, or 90, etc. My boss has a clock in his office where the hours, starting at 3 and going clockwise, are marked 0, - pi / 6, - pi / 3, - pi / 2, etc, until 2 o'clock is marked - 11 pi / 6. -- Gerry Myerson (gerry(a)maths.mq.edi.ai) (i -> u for email)
From: Andrew Usher on 4 Feb 2010 21:06 On Feb 4, 7:15 am, Bart Goddard <goddar...(a)netscape.net> wrote: > It is a fact that in almost all real calculations in > English units, one unit is chosen and it is decimated. Interesting word choice! > The only exception I can think of off the top of my > head is that carpenters like their denominators to be > powers of 2. Feet and inches are used together in construction, at least. > Otherwise, most people would calculate > using number like 15.53 feet. Every bit as easy as > the same calculation in the metric system. True. And anywhere that multiplication or division is required, mixed units will not be used as they become too difficult. Andrew Usher
From: Andrew Usher on 4 Feb 2010 21:08
On Feb 4, 3:21 am, nos...(a)nospam.com (Paul Ciszek) wrote: > >I even had one professor who worked in a system where all independent > >constants (c, q, permativitty of free space, etc) were all equal to > >1. > > I had an E&M textbook like that once...everything was fine until one of > the homework problems ended with having to find the dimensions of a > solenoid needed to satisfy some condition. I just couldn't turn the > ESU's or whatever back into meters and amps. And did you then realise just how silly SI is for EM calculations? Andrew Usher |