Gene: The only scales that measure mass are balance scales, because they balance something with something else whose mass is known. They will produce the same result on Earth, on the Moon or on Mars. As Joe has implied, Toledo scales use a balancing mechanism. (I actually have some doubts about Toledo scales, though; with true balance scales one takes note of the reference mass at the point of zero deflection, whereas the Toledo scales measure by deflection.) Commercial scales using springs or transducers measure the downward force, due to gravity, of the mass placed on them. They will produce different results on the Earth, on the Moon and on Mars. They measure weight. However, given that they are calibrated on the Earth and in the general geographic area where they are to be used (i.e., given the constancy of the ratio of measured force to actual mass), the units displayed can reliably indicate the mass placed on them. Bill Potts, CMS Roseville, CA http://metric1.org [SI Navigator] > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On > Behalf Of Gene Mechtly > Sent: July 08, 2001 12:47 > To: U.S. Metric Association > Cc: U.S. Metric Association > Subject: [USMA:14208] Re: Constitutionality > > > On Sun, 8 Jul 2001, Joseph B. Reid wrote: > > ... > > I meant scales that weigh in both pounds and kilograms should not be > > certified. Those scales are electronic and switchable between > pounds and > > kilograms. Those scales measure weight. Mechanical scales like Toledo > > ("Honest weight, no springs") measure mass. > > Nonsense, Joe. All honest scales (calibrated for legal trade), > both mechanical and electronic, measure mass and have measured mass for > many decades whether consumers have been aware or not that both pounds > and kilograms are legally defined as units of mass. > > Gene. >
