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On Wed, 01 Oct 2003 03:42:41 GMT, KU2S wrote:
On Tue, 30 Sep 2003 14:17:53 GMT, Gene Nygaard wrote: On Mon, 29 Sep 2003 23:38:14 -0500 (CDT), (Richard Harrison) wrote: Gene Nygaard wrote: "Look in the textbooks you used, and see if the authors have any footnotes citing the authority for whatever definition they use. My Random House American College Dictionary (circa 1950) says: "kilogram, n. Metric System. a unit of mass and weight, equal to 1000 grams and equivalent to 2.2046 pounds avoirdupois. For pounds, the same dictionary says: "Pound. 1. a unit of weight and of mass, varying in different periods and countries. Pounds and kilograms are different units for the same things, force and weight. Still haven't figured out that your claims that both kilograms and pounds are names of both a unit of mass and a unit of force is at odds with what Dave Shrader and Richard Clark have been telling us, have you? Okay people.... before this thread goes any further wrong than it already has.... Kilograms (base unit of measurement, the gram) are units of MASS. This is a measure of the amount matter in an object... Pounds are a unit of force, a measurement of the gravitational attraction a body has relative to another, reference, body. A 2 kilogram object will have the same mass on the earth as it does on the moon. A 60 pound object on the earth will have a weight of 10 pounds on the moon. If you kiddies are going to argue physics, you really SHOULD get your terms straight. God, pseudo-intellectuals really do begin to wear thin quite quickly... Raymond Sirois KU2S So what about those "meter kilograms" on my torque wrench? What's a poundal? Did NIST get it wrong, in what I pointed out in response to Richard Clark's challenge? http://physics.nist.gov/Pubs/SP811/appenB8.html#P To convert from to Multiply by pound (avoirdupois) (lb) 23 kilogram (kg) 4.535 924 E-01 pound (troy or apothecary) (lb) kilogram (kg) 3.732 417 E-01 [The 23 is a reference to a footnote in the printed and pdf versions, a note on a separate page in html] http://physics.nist.gov/Pubs/SP811/footnotes.html#f23 23 The exact conversion factor is 4.535 923 7 E-01. All units in Sec. B.8 and Sec. B.9 that contain the pound refer to the avoirdupois pound. How is the pound officially defined in Canada (Weights and Measures Act of 1953), in the United Kingdom (Weights and Measures Act of 1963), in South Africa, in New Zealand, in Australia, in Ireland and in other places as well as the United States, whose definition you can read at http://www.ngs.noaa.gov/PUBS_LIB/Fed...doc59-5442.pdf http://gssp.wva.net/html.common/refine.pdf But since you are so convinced that this is a "physics" problem, let's just review the last of the examples I quoted earlier from the textbook authors recommended by Dave Shrader. Francis Weston Sears and Mark W. Zemansky, University Physics, Addison-Wesley, 4th ed., 1970. [page 232] The quantity of heat per unit mass that must be supplied to a material at its melting point to convert it completely to a liquid at the same temperature is called the heat of fusion of the material. The quantity of heat per unit mass that must be supplied to a material at its boiling point to convert it completely to a gas a the same temperature is called the heat of vaporization of the material. Heats of fusion and vaporization are expressed in calories per gram, or Btu per pound. Thus the heat of fusion of ice is about 80 cal g^-1 or 144 Btu lb^-1. The heat of vaporization of water (at 100°C) is 539 cal g^-1 or 970 Btu lb^-1. Some heats of fusion and vaporization are listed in Table 16-2. Now, it doesn't take a whole lot of genius to figure out what the quantities are which are measured in those units with the -1 exponents, does it? But you don't even have to guess. Sears and Zemansky come right out and tell you. For you and some of the other slow-witted folks in this thread, here's a hint: Look for the seventh word in each of the first two sentences, that little word sandwiched in between the words "unit" and "that." Did you find it? ****************** That's as far as I went last time around. But this time we are dealing with real deep-rooted stoooopid, so I can't leave anything to the intelligence of the intended reader. That seventh word which I'm pointing out to you is spelled m-a-s-s. Do you see it now, Raymond? That's "mass," right? Now, let's compare the parallels in the construction here. In terms of the quantities being measured, this is expressed as quantity of heat per unit of mass and in terms of the units used to measure these quantities, it is expressed this way Btu lb^-1 Now, let's match them up: o The "quantity of heat" is measured in the units "Btu" o The "per" corresponds to the superscript -1 (that Btu lb^-1 could also be written as Btu/lb where the slash would correspond to "per") o The quantity "mass" is measured in the units "lb"; now that is the abbreviation, from one of its Latin names, for the units which Sears and Zemansky call pounds. Gene Nygaard http://ourworld.compuserve.com/homepages/Gene_Nygaard/ Gentlemen of the jury, Chicolini here may look like an idiot, and sound like an idiot, but don't let that fool you: He really is an idiot. Groucho Marx |
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