Actually I think a pound can be mass or weight. If you need to be specific
you should say "pound mass" (lbm = 0.454 kg) or "pound force" (lbf = 4.45
N). Now don't confuse pound force with a poundal (=0.138 N). Pound is also
a unit of money in Cyprus, Egypt, Ireland, Lebanon, Sudan, Syria, and United
Kingdom, not to mention a way of measuring the thickness of paper.
Coversion problem:
How many stray dogs are there in a pound?
Scott C
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
> Behalf Of Joseph B. Reid
> Sent: Tuesday, April 24, 2001 12:26 PM
> To: U.S. Metric Association
> Subject: [USMA:12423] Re: NASA and weight vs. mass
>
>
> Karl G. Ruling wrote in USMA 12422:
>
> >You're right, of course. I suspect that NASA used weight rather than mass
> >when writing in FFU about the mechanical arm in space because the unit of
> >mass in the foot-pound system is the slug.
>
>
> Wrong. The pound is defined in legislation as the unit of mass.
> Engineers
> have habitually used it as a unit of weight, and when that got the
> aeronautical engineers into trouble, they invented the slug which has no
> legal sanction behind it. The slug as a unit of mass does not appear in
> the 1970 edition of the Shorter Oxford Dictionary of the English Language,
>
> Physicists, with a better understanding of Newton, retained the pound as a
> unit of mass, and invented the poundal as the corresponding unit of force.
> The Oxford dictioary dates the poundal from 1879.
>
> Joseph B. Reid
> 17 Glebe Road West
> Toronto M5P 1C8 Tel. 416 486-6071
>
