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Re: pounds



To help confuse the issue let me point out that according to the NIST's
Special Publication 811 the avoirdupois pound is defined to be *exactly*
0.45359237 kg of *mass*. A 1 pound force (lbf) is the weight of a
1 lb mass in a standard gravitational field. *If* this standard field
strength is taken as the 'official' value of 9.80665 m/s^2 then a 1 lbf
corresponds to *exactly* 4.44482216152605 N of force.


I mention again my memory of the two systems of British units, in one the
mass is slugs and the force is pounds, in the other the mass is pounds and
the force is poundals.

And recall that Engineers will always be engineers and hence will define
the "kilogram force", kgf, as the force equal to the weight on earth of 1
kilogram mass.

Vern Lindberg
RIT Physics Department