Re: Moment of Inertia of a thin circular disc

qwerty wrote:
I = (Integral from 0 to 2pi)R^2 dm = M*R^2

That's incorrect, as the moment of inertia of a circular disc is M*R^2/2.

So what am I doing wrong?

The radius that you should be using in the integral is not R (the radius of the disc), but the distance from each differential bit of mass to the axis, and this distance isn't constant over a given pizza slice (no matter what axis you're using, which you haven't specified). Try integrating over slices with a constant distance to the axis. (If the axis is what I think it is, this should be easy.)

-- Ben
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