00:01
In this problem, we'll be analyzing this system here.
00:03
A block of mass m is dangling from a rope, which reaches over a pulley of radius r and mass m, to a frictionous center yoke of a cylinder of mass m and radius 2r.
00:20
The block is obviously being pulled down by gravity, which is going to exert a force, but not a torque on this cylinder.
00:29
So the torque on it must all be provided by friction.
00:36
So based on all of that information, we have to find what the acceleration of this system will be.
00:43
And in order to do that, we should look at all the forces in the system.
00:47
We already have the external ones written down.
00:49
We have friction pulling backward, gravity pulling down.
00:54
And the internal forces created by that are going to be the force on the block, which i'll call it fb.
01:01
The force on the pulley, which i'll call fp, and the force on the cylinder, which i'll call f .c...