Question

A 0.145 kg baseball is pitched at 42 m/s. The batter hits it horizontally to the pitcher at 58 m/s.

GIVEN:
m = 0.145 kg
v = 42 m/s

batter v = 58 m/s

a. Find the change in momentum of the ball.

p = mv

p = (0.145)(42)
p = 6.09
--> What velocity would I use? Would i use the velocity of the baseball

b. If the ball and bat are in contact for 4.6 x 10^-4 s, what is the average force during contact?

Answer 1

a) The sign of the velocity changes after the ball is hit. That makes the CHANGE in momentum equal to
M[42 -(-58)] = 0.145 kg * 100 m/s

b) Impulse
= (average force) x (time of contact)
= (change in momentum) = 14.5 kg m/s

Solve for the average force