Two identical metal balls are rolling without slipping along a horizontal surface with speed V. Each ball encounters a hill ('two-sided' ramp) of height H. The hill encountered by Ball A is frictionless, while Ball B rolls without slipping over its hill. How does the angular velocity of Ball A compare to that of Ball B when they reach the top of the hill?

The angular velocity of Ball A will be greater than the angular velocity of Ball B when they reach the top of the hill.

Explanation:

Angular velocity can be defined as how fast an object rotates relative to a given point or frame of reference.

The question said the hill encountered by Ball A is frictionless, so Ball A will continue to rotate at the same rate it started with even when it reached the top of the hill.

Ball B on the other hand rolls without slipping over its hill, i.e there's friction to slow down its rotational motion which thus reduces how fast Ball B will rotate at the top of the hill

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