23. Imagine a ball on a track where no energy is transferred between the ball and the track

or between the ball and the air around it. The ball starts from rest at the position labeled B

and moves along the track toward Positions D, E, F, and G. Place a dot on the highest

position the ball will reach before stopping and going back down the track. Explain why the

ball stop at that position? (Remember that no energy is transferred between the ball and the

track or between the ball and the air around it.)

The ball will stop at that position because of the fact gravitational potential energy and motion energy (kinetic energy) both depend on the mass of the ball.

Explanation:

Position 1. As the ball moves downwards at one end, its gravitational potential energy will reduce and its motion energy (kinetic energy) will go up, but its motion energy will not raise sufficiently for it to go on the previous Position 1.

Position 2. As the ball moves downwards at one end, its gravitational potential energy will alter into motion energy (kinetic energy), and as the ball moves upward the other end, its motion energy will be altered back into the equal amount of gravitational potential energy it begun with.

Position 3. As the ball moves downward at one end, its motion energy (kinetic energy) will be summed to its gravitational potential energy, which gives it sufficient energy move higher than it started.

The position that the ball will reach depend on the weight of ball because motion energy and gravitational potential energy depends on the ball's mass.