Question

A boy on a bicycle is resting at the top of a hill. Then, he rides his bicycle
down the hill. Describe how the boy's potential and kinetic energy differ at the
top, middle, and bottom of the hill.

Answer 1

At the top of hill, Potential energy is high and Kinetic energy is almost Zero.

At the middle of hill, Potential energy and Kinetic energy are almost equal.

At the bottom of hill, Potential energy is zero and Kinetic energy is high.

Explanation:

PE = mgh

Where, m =Mass

            g= Acceleration due to gravity

             h = Height

KE = 0.5 mv²

Where, m =Mass

             v = Velocity

1. At the top of hill, there is a considerable amount of height. Hence, it has the higher potential energy. And the kinetic energy store is zero. It is due to the fact initial velocity is zero.
2. At the middle of hill, there is a half amount of height. Hence, it has the moderate potential energy. And the kinetic energy store is also moderate It is due to the fact particle gains some amount of velocity.
3. At the bottom of hill, the height is equal to zero. Hence, it has the zero potential energy. And the kinetic energy store is maximum. It is due to the fact final velocity gained by the body is maximum.