Charles Momsen wrote:
Nope, you just passed my test. Great job, but your explaination could have
been a bit simpler by pointing out the torque vector is an imaginary
convention (the forces involved in it are orthogonal to the vector which is
a result of cross product operation), whereas thrust is a real force. Well
done Ian!

Marty wrote:
Tell you what, hold out your arm, I'll clamp a 48" monkey wrench down on
your wrist, then we'll hang a 30 pound weight at the distal end of the
wrench, this will produce an "imaginary" torque of 120ft-lbs on your
wrist. *Then you can tell us if it's a real thing or not.....


That would produce TWO torques, one at wrist and one at shoulder.

When evaluating these kinds of things, it is well to remember that a
force which produces no motion does no work... OTOH energy does not
cancel itself out, as "Charles Momsens" first post seems to suggest.

DSK