>Hilmar,
>
>>kilogram for mass (NOT for weight)
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>And it seems fundamentally silly to define mass by using weight, as in the magnetic force proposal. F = m * a. Weight = mass * gravitational acceleration. In college we always had to use lbm and lbf when talking about pounds-mass and pounds-force (yeah most of my engineering classes were pre-SI focus). m = F / a but this means you have to have a constant a to determine m.
>
>I don't believe the gravitational force is constant enough over the entire face of the earth to make that a feasible solution. Scientists on the moon or Mars will require a different magnetic force to measure a standard kilogram. So there is no "one" definition of a kilogram using the magnetic force mechanism.
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>later update There is another infeasbility in this scheme. The gravitational acceleration between two bodies is a function of the two masses and the distance between them. So the magnetic force scheme wants to define mass as a function of mass, you can't do that.
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>>and some unit for luminescense, which I forget.
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>lumen (I think) candela is the another old measure the amount of light on a 1 foot square one foot from a candle.
Makes one ask if there might have been a "campanela" before there was a "bel", a "campanela" possibly being the measure of sound on a 1 foot square one foot from a bell < s >
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