At the risk of another War of Independence.....
When I went to school here in the UK we were in the transition period when
we worked in both imperial and SI units, and to my understanding:
Torque is measured in lbf ft, pound-force feet, equivalent to 1.4 Nm
Energy is measured in ft lbf, foot pound-force, equivalent to 1.4 J
So 1 lbf ft is the rotational torque exerted by pulling a 1 foot lever with
a force of 1 pound, while 1 ft lbf is the energy given to a body by
exerting a force of 1 pound over a distance of 1 foot. (note both
measurements have the same dimensions)
What I always had to think very hard about in the "old" system was the use
of poundal instead of lbf - it all seemed so much easier in SI, which I've
been thinking in for the last 30 years, except of course for units like BHP
and for large capacity engines, CI.
Jon Hobden, Horley, England
(Off to Goodwood Festival tonight, and looking forward to seeing some of
your history
http://www.goodwood.co.uk/biweb/Salt_Flat_Racers.html
it will be interesting to see how they negotiate the hillclimb!)
Date: Wed, 21 Jun 2000 15:46:01
From: "Lawrence E. & Cathy R. Mayfield" <lemay@hiwaay.net>
Subject: Terminology Question...
Maybe I can start a war...
I went to school and learned that torque was "ft-lbs".
I often see and hear nowadays the term "pounds - feet"
So whay are all those guys WRONG! I know my terminology is absolutely, 100%
correct, so whay are Thos other people using the completely wrong term of
pounds-feet?
:) mayf
Seriously what is the genesis of the different terms?
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