00:01
Okay, so the engine cuts out, and this is going to start to rotate, and we need to figure out the angular acceleration that we'll have.
00:11
Now, we can look at this in terms of the net torque acting on this thing, where it's going to rotate about this end here.
00:18
So the net torque is equal to the moment of inertia of the system, which is going to be the bar as well as the bucket, which is going to work treating like a point mass.
00:30
And that's multiplied by the angular acceleration.
00:35
And so we can set this i -alpha equal to the sum of those torques.
00:41
So for this system, the rotational inertia of the bar around this point will be due to the center mass of the bar.
00:50
So one -third ml squared.
00:55
This is a long massive rod.
01:00
We're treating it like.
01:01
So it's moment of inertia between one third ml squared...