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

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SUMMARY

The discussion focuses on calculating the angular velocity and period of oscillation for a solid disc of mass m and radius R, pivoting around a point on its circumference. The moment of inertia is given as I = (mR^2)/2, and the small angle approximation sin(theta) ≈ theta is assumed. The confusion arises from the problem statement's wording, specifically the distinction between "point on circumference" and "point on its surface." Clarification of these terms is essential for accurate problem-solving.

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Homework Statement



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.

Homework Equations



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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 :confused: .
 
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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?
 
HallsofIvy said:
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?

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. :confused: ^ 100000

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

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