The two rotating systems shown in the figure differ only in that the two identical movable masses are positioned at different distances from the axis of rotation.If you release the hanging blocks simultaneously from rest,and if the ropes do not slip,which block lands first?
A) The block at the left lands first.
B) The block at the right lands first.
C) Both blocks land at the same time.

Question

The two rotating systems shown in the figure differ only in that the two identical movable masses are positioned at different distances from the axis of rotation.If you release the hanging blocks simultaneously from rest,and if the ropes do not slip,which block lands first? 
A) The block at the left lands first. 
B) The block at the right lands first. 
C) Both blocks land at the same time.

Quizplus · Accepted Answer

The block on the right will land first. This is because it has a larger moment of inertia than the block on the left, due to its greater distance from the axis of rotation. As a result, it will require more torque to rotate, and will therefore experience a greater acceleration than the block on the left. Since both blocks are released from rest, the block on the right will have a head start and will reach the ground first.

The Two Rotating Systems Shown in the Figure Differ Only