Question

1. A ball is at rest on the top of a hill (see the figure).

At the top of the hill, the ball will have [the maximum value of its, no, the minimum value of its] gravitational potential energy and [no, the maximum value of its] kinetic energy. If the ball rolls down the hill then, its [gravitational potential energy, kinetic energy] is converted to [gravitational potential energy, kinetic energy] when it gets to the ground.

2. Get your stopwatch ready and prepare to drop the object from the height h you selected in the previous step. You should drop the object so its [bottom, top, middle] part is initially at the height h. The initial speed of the ball [zero, 9.8 m/s, 9.8 m/s^2, depends on the height h] You'll need to measure the time from when the ball leaves your hand to exactly when it hits the ground [ for the first time it bounces, after it bounces and then comes to rest, both the first time and then after it bounces; then average the two times]
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Answer 1

1. At the top of the hill, the ball will have the maximum value of its gravitational potential energy and the minimum value of its kinetic energy. As the ball rolls down the hill, its gravitational potential energy is converted to kinetic energy when it gets to the ground.

2. When dropping the object, you should drop it so its top part is initially at the height h. The initial speed of the ball will be zero since it starts from rest. To measure the time it takes for the ball to hit the ground, you should start the stopwatch when the ball leaves your hand and stop it when the ball hits the ground for the first time. It is recommended to perform multiple trials and calculate the average time to minimize errors.