(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A uniform disk of radius R is cut in half so that the remaining half has mass M. (Figure (a))

1. What is the moment of inertia of this half about an axis perpendicular to its plane through point A? Express your answer in terms of the given quantities.

2. Why did your answer in part A come out the same as if this were a complete disk of mass M? Express your answer in terms of the given quantities.

3. What would be the moment of inertia of a quarter disk of mass M and radius R about an axis perpendicular to its plane passing through point B? (Figure (b))

2. Relevant equations

Moment of inertia of a semicircle.

[itex]I_{P}=I_{cm}+Md^{2}[/itex]

[itex]I_{cm}=I=\sum_{i}m_{i}r_{i}^{2}[/itex]

3. The attempt at a solution

Is d=R?

1. [itex]I_{P}=I_{cm}+Md^{2}=MR^{2}+MR^{2}=2MR^{2}[/itex]

Does this make sense?

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# Homework Help: Moment of inertia of a semicircle

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