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Re: torque

> >well, I don't know about torque, but force requires motion for it's
> >definition - there is no acceleration without motion, or at least a
> >change in the rate of it.  relatively speaking anyway....
> 
> I think you are a little off on this one, Huw.  Force can and does exist
> without acceleration.  Imagine a block of concrete sitting on the ground.
> You push on it from the right.  You are exerting a force of some amount
> (let's say 100 pounds for simplicity).  Why doesn't the block move?

etc. etc.

of course the fly in the ointment is that the nice pretty little
equations (like F=ma) I remember from early physics courses are
operative only in a frictionless universe... been there but came back,
kept dropping my coffee, forgot to recalibrate my assumptions...

in "reality" F = ma + some other term which reflects heat lost to
friction (I presume in your example I will have at least warmed up the
concrete block a tiny bit), or tied up temporarily as potential energy
in the elasticity of the components in the system.  ("grunt in" = "grunt
out" - "sweat")

but anyway... we drift

-- 
Huw Powell

http://www.thebook.com/human-speakers

82 Audi Coupe; 84 4kq; 85 Coupe GT
http://www.nh.ultranet.com/~human