Question

The rotating systems shown in the figure differ only in the placement of the two identical masses on each system with the block on the left having its two masses at radius R and the one on the right having its two masses at 0.5R. Which block will hit the floor first when both are released from rest at the same time and same height from the floor.

A. The block on the left lands first.
B. The block on the right lands first.
C. Both blocks land at the same time.
D. Do not have enough information to know which lands first.

Answer 1

The block on the left lands first. The block on the right has two masses at radius 0.5R, while the block on the left has two masses at radius R. The smaller radius of the masses on the block on the left allows it to rotate faster and hit the floor first.

This correct answer is B.

Step-by-step explanation:

The block on the left lands first. When both blocks are released from rest at the same time and at the same height from the floor, the block on the left with two masses at radius R will hit the floor first.

This is because the moment of inertia of a rotating object depends on both the mass and the radius of the object.

The block on the left has a smaller moment of inertia due to the smaller radius of the masses, which allows it to rotate faster and reach the floor first.

This correct answer is B.