PHYSICS 1111 Quiz 14 - Moment of inertia of a solid

PHYSICS 1111 

Quiz 14

Moment of inertia of a solid disk: I = ½ MR2

Moment of inertia of a solid sphere: I = 2/5 MR2

Moment of inertia of a ring: I = MR2

Moment of inertia of a hollow sphere: I = 2/3 MR2

1. (4 pts) Consider a 5.0 kg solid disk with a 2.0 m radius, which is initially spinning on its central axis in a counterclockwise direction with an angular speed of 5.0 rad/s. What is the angular momentum of this spinning disk?

2. (4 pts) Now, a second object, which is not initially rotating, is dropped on top of the first and they stick together. The final angular speed of the two objects stuck together is 2.0 rad/s in the same counterclockwise direction. What is the magnitude of the moment of inertia of the second object?

3. (2 pts) What was the initial rotational kinetic energy of the spinning disk in question 1. ? This means before the object from question 2 was dropped.