Re: moment of inertia of a cube

bob@xxxxxxxxxxxxxx wrote:
I calculated today that the moment of inertia of a cube does not
depend on the axis of rotation. Is there a real intuitive way to see
this?

I've read a few of the responses, but I am wondering what question you are really asking- the moment of inertia of *any object*, being defined as: I = Integral(r^2 dm) is always defined in terms of a coordinate origin, which is taken to be on the axis of rotation (except for the parallel axis theorem). So, unless your mass distribution falls off as 1/r^2 irrespective of your coordinate origin (something clearly unphysical), there will be a dependence on where the axis of rotation is.

Or am I missing something? After all, it's friday afternoon, and I spent the morning fighting with my microscope...

--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.

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