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Re: poundals



There are two British systems of units, though the second has virtually
disappeared.

There are two units called "pound" (even worse). One is the usual unit
of force, and in that system the mass unit is the slug. As g = 32,
we find that a slug weighs 32 pounds. The pound MASS is so named because
it WEIGHS a pound. It is thus 1/32 slug.
In the system where the pound-mass is the unit of mass the unit of force
is the poundal. A poundal is thus 1/32 of a pound-force.

It's enough to drive you nuts, and who cares? It will all be metric
anyway some day, and the only British system that is even mentioned in
physics books any more is the slug (mass), pound (force) system.

Yes there is a pound mass, but why worry? It weighs a pound! Keeps the
chemists happy I guess. But for heaven's sake don't take this all up
with your students. Talk about trivia.
J. Epstein