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On Thu, 25 Sep 2003 12:13:47 GMT, Dave Shrader
wrote: Gene, thanks for the compliment in calling the Program Chief Engineer of the USAF MX [Peacekeeper] Re-Entry System/Re-Entry Vehicle a fool. It says a lot about you. I forgive you. Dave, W1MCE + + + Gene Nygaard wrote: not concerned enough about the possibility that fools like you Since you aren't honest enough to tell us exactly what Sears and Zemansky said in 1956, I'll tell everyone what they said in 1970. If there are any significant differences, feel free to point them out. This thing is, I know that Sears and Zemansky weren't going to lie about this, because they grew up using poundals, which are by definition the force which will accelerate a MASS of 1 lb at a rate of 1 ft/s². Francis Weston Sears and Mark W. Zemansky, University Physics, Addison-Wesley, 4th ed., 1970. [page 3] 1 pound mass = 1 lbm = 0.45359237 kg [The actual number will, of course, be different in 1956, because the U.S. didn't adopt this definition until 1959 (it had been in use in Canada since 1953, six years before the international redefinition).--GAN] [page 4] We select as a standard body the standard pound, defined in section 1-2 as a certain fraction (approximately 0.454) of a standard kilogram. [page 59] In setting up the mks and cgs systems, we first selected units of mass and acceleration, and defined the unit of force in terms of these. In the British engineering system, we first select a unit of force (1 lb) and a unit of acceleration (1 ft s^-2) and then define the unit of mass as the mass of a body whose acceleration is 1 ft s^-2 when the resultant force on the body is 1 lb. end quote Now, Sears and Zemansky might be incompetent for not allowing for the fact that there are going to be people out there who are too blamed stupid to understand that that adjectival phrase "British engineering" has some meaning, and that it identifies one particular limited subset of the British units. It's perhaps even understandable, because that fact would be quite clear to anyone who, like them, had grown up using poundals in a "British absolute" system of units. However, that doesn't change the fact that you are in fact one of the people who are that stupid. -- Gene Nygaard http://ourworld.compuserve.com/homepages/Gene_Nygaard/ "It's not the things you don't know what gets you into trouble. "It's the things you do know that just ain't so." Will Rogers |
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