Physics-
General
Easy
Question
Two identical disks are positioned on a vertical axis. The bottom disk is 0 wrotating at angular velocity and has rotational kinetic energy KE0 . The top disk is initially at rest. It is allowed to fall, and sticks to the bottom disk. What is the rotational kinetic energy of the system after the collision?
. 
- (1/4) KE0
- (1/2) KE0
- 4 KE0
- 2 KE0
The correct answer is: (1/2) KE0
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