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A boy strikes a baseball with a bat, giving it an impulse I. He strikes another ball with the same force, but this time the bat stays in contact with the ball for twice as long. What is the new impulse?

1. half the original impulse
2. the original impulse
3. twice the original impulse
4. four times the original impulse

Correct answer: twice the original impulse

Solution

Impulse J = F * t; with F constant and t doubled, the impulse doubles.

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