Question

A 0.145 kg baseball pitched at 38.0 m/s is hit on a horizontal line drive straight back toward the pitcher at 55.0 m/s. If the contact time between bat and ball is 3.40×10−3 s, calculate the average force between the ball and bat during contact.

Answer 1

a = (Vf - Vo) / t,
a = (55 - 38) / 0.005 = 5000 m/s^2.

F = m*a = 0.145 * 5000 = 725 N.

Answer 2

CORRECTION:

a = (V-Vo)/t
a = (-55-38)/3.4*10^-3 = -27,353 m/s^2.

F = m*a = 0.145 * (-27,353) = -3966 N.