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السؤال رقم 4 في هذه الصفحة

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Solution:- The initial momentum pi of the ball will be, pi = mvi To obtain the initial momentum pi of the ball, substitute 46.0 g for the mass of the ball and 52.2 m/s for vi in the equation pi = mvi, pi = mvi = (46.0 g) (52.2 m/s) = (46.0 g×10-3 kg/1 g) (52.2 m/s) = 2.4 kg.m/s = (2.4 kg.m/s) (1 N/1 kg.m/s2) = 2.4 N.s As the final speed of the ball is zero, thus the final momentum pf of the ball will be zero. So, pf = 0 To find out the impulse J imparted to the ball, substitute 2.4 N.s for pi and 0 for pf i n the equation J = pi – pf, J = Δp = pi – pf = 2.4 N.s -0 = 2.4 N.s Therefore the impulse J imparted to the ball would be 2.4 N.s. b) The impulse J imparted to the club is just opposite that imparted to the ball. Therefore the impulse J imparted to the club will be 2.4 N.s. c) To obtain the average force F exerted on the ball by the club, substitute 2.4 N.s for Δp and 1.20 ms for t in the equation F = Δp/ Δt, F = Δp/ Δt = 2.4 N.s/1.20 ms = (2.4 N.s)/((1.20 ms)(10-3 s/1ms)) = 2000 N From the above observation we conclude that, the average force F exerted on the ball by the club would be 2000 N .