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Originally Posted by KiwiBacon
To continue along those lines:
Work done (Joules) = Torque (Nm)*Rotation (radians)
Power (watts or joules/second) = Torque(Nm) * Rotating speed (radians per second).
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if this was right it would mean that work is measured in N * m * radians. it's just newton meters, which are equivalent to joules. as well, power is work/time and work is measured in newton meters, time in seconds, this would mean power = Nm/s, not Nm*radians/s.
if you want a vector definition of torque, then it's the cross product of the force and the distance from the point where the torque is applied (and it's r X F, not F X r, i got screwed with that mistake on my exam this year). it's pretty much a measure of a rotational force on a point, with no time or movement involved.
when applying it to cars, it's how much rotational force the engine can apply at a certain rpm. horsepower is how much work the engine can do in a certain ammount of time.
since work (w) equals a force over a distance (F*d) then power is how quickly you can apply that force over that distance. so if you have 100 Watts (N*m/s) you can apply 100 Newtons over 1 meter in 1 second, 50 newtons over 2 meters in 1 second, etc.
hope this clarified things up, i find it more difficult to think of torque relating to cars vs torque relating to wrenches and such (although a wrench system is different from what you think it is, as i learned in mechanics I this year)