A rubber ball, of mass 250 g, travelling at 4.0 ms−1 hits a wall perpendicularly and bounces off with a speed of 3.0 ms−1. The time of impact is 0.2 s.Which of the following gives the best estimate of the average force exerted by the wall on the rubber ball?
a. 0.25 N
b. 1.25 N
c. 8.75 N
d. 50.0 N