# Average Force on a Batted Ball

Average Force on a Batted Ball

This Demonstration calculates the force exerted on a baseball by a swinging bat as a function of the initial speed of the pitched ball and the final speed of the batted ball . The change in momentum of the ball is equal to the impulse, which is the integral of the force over time: F(t)dt. Thus the average force is , where the ball is in contact with the bat between times and , and is the momentum. High-speed photography shows that the time interval - is approximately 0.001 second. The weight of a regulation baseball is 5.25 ounces, or 5.25/16 pounds, which corresponds to a mass of slugs, using the Imperial system of units, with length in feet, time in seconds, mass in slugs, and force in pounds.

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(p()-p())/(-)

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p=mv

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5.25/(16×32.2)=0.0102

The average force is then given by .

F=m(-)/(-)=0.0102(-)/0.001

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The Demonstration also animates the collision of the pitched ball with the swinging bat.