00:01
So first we should find the moment of inertia about the hinge pin.
00:08
So i sub p would be equal to 1 half mr squared plus mh squared.
00:17
And this is simply due to the parallel axis theorem.
00:21
So we can calculate this.
00:22
This would be 1 half times 2 .5 kilograms multiplied by 0 .21 meters, quantity.
00:31
Squared plus 2 .5 kilograms multiplied by 0 .97 meters quantity squared equals 2 .41 kilograms meters squared.
00:47
Now we for h we simply used the distance, the point of support for the physical pendulum which is essentially 0 .21 meters plus 0 .76 meters equaling, of course, 0 .97 meters.
01:10
This would be away from the center of the disk.
01:14
So that's how we would use the parallel axis theorem.
01:17
And that's how we find.
01:18
And that's how we're finding h in order to plug in to the parallel axis theorem.
01:22
So with the moment of inertia about the hinge pin, we can then find part a...