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Ninjazn_Element
A baseball (m = 149 g) approaches a bat horizontally at a speed of 40.3 m/s (90 mi/h) and is hit straight back at a speed of 49.7 m/s (111 mi/h). If the ball is in contact with the bat for a time of 1.10 ms, what is the average force exerted on the ball by the bat? Neglect the weight of the ball, since it is so much less than the force of the bat. Choose the direction of the incoming ball as the positive direction.
Strategy: 1) Find the impulse on the ball. Impulse is equal to change in momentum. Or: \[I=\Delta p=mv'-mv \]2) Find the average force with equation: \[I=F\Delta t \]