Why does a tennis ball bounce higher on hills than in plains ?

Why does a tunnis ball bounce heigher on a hill than on plains?

Why has the National Forest Commission of India recommended a relatively larger forest cover for hills than for plains?

A tennis ball with (small) mass m_(2) rests on the top of a basketball of mass m_(1) which is at a height h above the ground, and the bottom of the tennis ball is at height h+ d above the ground. The balls are dropped. To what height does the tennis ball bounce with respect to ground? (Assume all collisions to be elastic and m_(1)gt gt m_(2))

Why does it take longer to cook food in the mountains than in the plains?

A tennis ball bounces down a flight of stairs, striking each step in turn and rebounding to half to height of the step. The coefficient of restitution is

Nalini has 15 tennis balls. She gives 7 tennis balls to her friend. Her father brings back another 5 tennis balls for her. How many tennis balls does she have now?