Leigh wrote:
| Of course the rotational form of the second law to which you refer can
| always be used with an accelerating origin provided one accounts for
| torques due to so-called "frame forces"*. In those special choices of
| origin for which frame forces produce zero net torque one may apply the
| law thoughtlessly without suffering an error in the answer. However,
| would it not be better to apply the law thoughtfully and recognize that
| the frame force forces contribute zero net torque with proper choice of
| origin? Is this so different from choosing any other origin because it
| simplifies calculation?
I agree. But I was referring to cases even farther "out of the box" (than
merely judiciously choosing a COMMON (but accelerating) origin for torques,
positions and velocities, - as in the example noted at the very end of John
Mallinkrodt's quote). I refer to the possibility of using different origins
for torques, positions and/or velocities.