Problem 4: A 0.4 kg ball traveling with the speed of 15 m/s strikes a rigid wall and rebounds elastically. If the ball is in contact with the wall for 0.045 s, what is (a) the momentum imparted to the wall and (b) the average force exerted on the wall?
Given mass of the ball, m = 0.4 kg Initial velocity, vi = -15 m/s
Final velocity, vf = 15 m/s Time, Δt = 0.045 s
Required (1) Momentum imparted to the wall, Δp
(2) Average force exerted on the wall, Fav
Formulae Δp = mvf – mvi Fsv = (Δp/Δt)
Solution Put values in the above formulae