Two identical balls are at rest side by side at the bottom of a hill. Some time after ball A is kicked up the hill, ball B is given a kick up the hill. Ball A is headed downhill when it passes ball B headed up the hill. At the instant when ball A passes ball B,
A) it has the same position and velocity as ball B.
B) it has the same position and acceleration as ball B.
C) it has the same velocity and acceleration as ball B.
D) it has the same displacement and velocity as ball B.
E) it has the same position, displacement and velocity as ball B.

Question

Quizplus · Accepted Answer

At the instant when ball A passes ball B, both balls are at the same position on the hill, and since they are on the same slope, they experience the same acceleration due to gravity. However, their velocities are different because they are moving in opposite directions.

Two Identical Balls Are at Rest Side by Side at the Bottom