Hey Everyone, have another doosie for eveyone. I've been crackin' away at it for some time, but to no avail. Here it is:(adsbygoogle = window.adsbygoogle || []).push({});

A semicircular of mass m and radius R is resting on a rough surface. the center of mass is given by 2R/pi, and that's about it.

a) Calculate the moment of inertia of the semicircular ring about its center of mass

b) The ring is displaced by a small angle; find the period T (no slip). Ignore all terms higher than first order theita

c) The surface is now frictionless. Given a small displacement, as well as ignoring second order and beyond theitas, find the Period T (with slip)

Okay, so for part a I thought it would be easiest if I calculated the Moment of inertia about the center of what would be the whole ring, followed by the use of the parralel axis theorem. Problem is, or at least I think it is, is that my integration for the moment yielded mR^2, which doesn't jive well with me. Am I doing something wrong. In the integral, I took out the R^2 because the distance was the same for all mass elements, so the integral became (after some substitution) the integral of dTheita from 0 to pi. Am I missing something.

As for the other two, I know the Period of a physical pendelum is given by the equation T=2pi*sqrrt(I/mgh), but once again I feel that that isn't the whole story. Can someone ;ead me in the right direction? Thanks a bunch

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# Homework Help: Ridiculously complex mechanics problem

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