physics(easy)
posted by Anonymous .
A superball of mass m, starting at rest, is dropped from a height hi above the ground and bounces back up to a height of hf. The collision with the ground occurs over a total time tc. You may ignore air resistance.
(a) What is the magnitude of the momentum of the ball immediately before the collision? Express your answer in terms of m, hi, and g as needed (enter h_i for hi, h_f for hf, and t_c for tc).
(b) What is the magnitude of the momentum of the ball immediately after the collision? Express your answer in terms of m, hf, and g as needed (enter h_i for hi, h_f for hf, and t_c for tc).
(c) What is the magnitude of the impulse imparted to the ball? Express your answer in terms of m, hi, hf, tc, and g as needed (enter h_i for hi, h_f for hf, and t_c for tc).
(d) What is the magnitude of the average force of the ground on the ball? Express your answer in terms of m, hi, hf, tc, and g as needed (enter h_i for hi, h_f for hf, and t_c for tc).

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