Question

1. A disk of mass M=160kg and radius R=0.40m spins with an initial rate of 12 revolutions per second. Because of friction in the bearing, the disk slows down at a uniform rate. After 20 minutes it comes to a stop.

(a) How many revolutions does the disk make before coming to rest?

(b) What is the moment of inertia of the disk?

(c) Find the angular acceleration of the disk as it slows down.

(d) Find the torque that acts on the disk while it is slowing down.

Answer #1

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