A 1.2 kg ball drops vertically onto a floor, hitting with a speed of 20 m s-1. It rebounds with a speed of 10 m s-1.
(a) What impulse acts on the ball during the contact?
(b) If the ball is in contact with the floor for 0.020 s, what is the average force exerted by the floor? What is the average force exerted by the ball?