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Gene Nygaard wrote in message . ..
Channeling a curmudgeon for some reason - must be the fact that I've been getting skunked by the weather for two weeks. Well, now, in this fuzzy dreamworld you inhabit, what exactly is the standard for a pound? Probably the original standard was 1.397 the weekly average of the King's morning BM. What is the nature of this standard? Something electrical, something mechanical, or what? Scatalogical Who made it the standard? When exactly was it made the standard (just the year will do)? The King, of course, who else? And of course it changed from generation to generation, just like the inch. Where is the standard kept, and who maintains it? A silver "repository" in a palace somewhere. Now for the bonus question: In addition to the system in which slugs are the units of mass, there is another, much older English foot-pound-second system in which the poundal is the derived unit of force. It is the force which will accelerate the base unit of mass in this oldest English subsystem of coherent mechanical units at a rate of 1 ft/s². Now, fill in the blank, please: The base unit of mass in this oldest fps system is the _____________. (Hint: it is the "p" in this fps system.) When the poundal system was invented back around 1879, not only did slugs not exist but also pounds force had never been well-defined units. This was before anybody ever started picking some "standard acceleration of gravity" which is an essential ingredient in the definition of those pounds force. Even today, pounds force don't have an official definition, at least in the United States. We often borrow the value for the standard acceleration of gravity which is official (adopted by the CGPM in 1901, long after the poundal system was in use and the dyne system in cgs units) for the purpose of defining kilograms force, i.e. 9.80665 m/s². But other values are also used for this purpose, such as 32.16 ft/s² (you still commonly see this used in ballistics with a formula for kinetic energy in a foot-grain-pound force-second system E = m v²/450240). Let's keep it simple and just use kilograms x furlongs / fortnight^2... |
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Personally, my favorite is schrader valve stem threads. 7.5 millimeter x
32 threads per inch. Go figure. Let's keep it simple and just use kilograms x furlongs / fortnight^2... |
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