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

A uniform circular disk has radius 36 cm and mass 350 g and its center is at the origin. Then a circular hole of radius 7.2 cm is cut out of it. The center of the hole is a distance 10.8 cm from the center of the disk. Find the moment of inertia of the modified disk about the origin.

2. Relevant equations

I=.25mr^2 (I think...!)

3. The attempt at a solution

I tried finding the moment of inertia for both the hole and the disk and subtract the hole, but that didn't work.

I'm not sure if that equation I posted is correct, I just googled it.

How am I supposed to find the mass for the moment of inertia equation?

At this point I just wish there was a straight up equation for it! Please help!

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# Homework Help: Moment of Inertia for a Disk with Hole

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