Question

a tennis ball is thrown against a vertical concrete wall that is fixed to the ground. the ball bounces off the wall. how does the force exerted by the ball on the wall compare with the force exerted by the wall on the ball?
a the force exerted by the ball is greater.
b the forces exerted by the ball and the wall have the same magnitude.
c the force exerted by the ball is smaller.
d the relative magnitudes of the forces cannot be determined without knowing how long the ball and the wall are in contact.

Explanation:

According to Newton's Third Law of Motion, when one object exerts a force on a second object, the second object exerts an equal - in - magnitude and opposite - in - direction force on the first object. In the case of the tennis ball and the wall, the force exerted by the ball on the wall and the force exerted by the wall on the ball are action - reaction forces. So these two forces have the same magnitude.

Answer:

B. The forces exerted by the ball and the wall have the same magnitude.