## College Physics (4th Edition)

(a) The magnitude of the change in momentum of the ball is $11.31~kg~m/s$ (b) The impulse exerted on the ball by the bat is $11.31~kg~m/s$ (c) The magnitude of the average force exerted on the ball by the bat is $3770~N$
(a) We can find the change in velocity: $\Delta v = v_f-v_0 = (-37~m/s)-(41~m/s) = -78~m/s$ We can use the magnitude of the change in velocity to find the magnitude of the change in the ball's momentum: $\Delta p = m~\Delta v$ $\Delta p = (0.145~kg)(78~m/s)$ $\Delta p = 11.31~kg~m/s$ The magnitude of the change in momentum of the ball is $11.31~kg~m/s$ (b) The impulse exerted on the ball by the bat is equal to the ball's change in momentum, which is $11.31~kg~m/s$ (c) We can use the impulse to find the average force exerted on the ball by the bat: $F~t = J$ $F = \frac{J}{t}$ $F = \frac{11.31~kg~m/s}{0.0030~s}$ $F = 3770~N$ The magnitude of the average force exerted on the ball by the bat is $3770~N$