posted by sugin .
a 200g tennis ball approaches a racket at 20m/s is in contact with the racket for 0.008s and the ball rebounds at 4m/s. find the average force that the racket exerted on the ball
F = Δp/Δt = [m•v2 –(- m•v1)]/ Δt =
= m• (v2+1v1)/ Δt =
0.2(20+4)/0.008 =600 N