A heavy rock and a light rock are dropped from the same height.The forces exerted on them by air are negligible.Which of the following statements about these rocks are correct? (There could be more than one correct choice.)
A)Both rocks have the same kinetic energy when they reach the ground.
B)Both rocks have the same speed when they reach the ground.
C)The heavier rock reaches the ground before the lighter rock.
D)Just as they were released, the two systems consisting of each rock and Earth had the same amount of gravitational potential energy.
E)When they reach the ground, the heavier rock has more kinetic energy than the lighter rock.

Question

Quizplus · Accepted Answer

Both rocks have the same speed when they reach the ground due to the acceleration of gravity being constant for all objects. However, the heavier rock has more kinetic energy because kinetic energy depends on both mass and speed, and the heavier rock has more mass.

A Heavy Rock and a Light Rock Are Dropped from the Same