# Angular velocity and period of a disc rotating about point on circumference

1. Apr 23, 2007

### rcw110131

1. The problem statement, all variables and given/known data

Find the angular velocity and period of oscillation of a solid disc of mass m and radius R about a point on it’s surface.

2. Relevant equations

?????

3. The attempt at a solution

This is really giving me trouble because it seems like a SHO problem mixed with a rotational motion problem, and I don't even know where to start. Any help would be greatly appreciated .

2. Apr 23, 2007

### HallsofIvy

Staff Emeritus
Is that all you are given, exactly the way the problem is stated? That's exactly like "find the velocity of an object moving in a straight line"! An object can move with almost any velocity and can rotate with almost any angular velocity. Oh, and in your title you say "rotating about point on circumference" but your problem says "about a point on it’s surface". Those are not at all the same thing. Which is correct?

3. Apr 23, 2007

### rcw110131

Yes, the disc pivots around a point on its circumference, according the very unhelpful diagram my professor gave me. She's also Sri Lankan so her English isn't great, which would explain the "surface" part. And the question is a direct quote, that's all I have. ^ 100000

EDIT: sorry, she also gave us: "I = (mR^2)/2, Assume sin(theta)≈theta"