A0.145 kg baseball pitched at 35.0 m/s is hit on a horizontal line drive straight back at the pitcher at 56.0 m/s. if the contact time between the bat and ball is 5.00 × 10−3 calculate the force (assumed to be constant) between the ball and bat.

2639 N

Explanation:

The impulse on the baseball is given by:

(1)

where F is the force exerted on the ball and the contact time between the bat and the ball.

The impulse is also equal to the change in momentum of the ball:

(2)

where m is the ball's mass, v is its final velocity, u is its initial velocity.

By using (1) and (2) simultaneously we can write an expression for F, the force exerted on the ball:

where:

m = 0.145 kg

u = 35.0 m/s

v = -56.0 m/s

Substituting,

and the negative sign means that the force is simply in the opposite direction to the ball's initial direction.

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