A ball is thrown against a wall, bounces off, and is caught. The number of impulses acting on the ball is
1) one.
2) two.
3) three.
4) none.
The greatest impulse occurs when the ball
5) is thrown.
6) bounces against the wall.
7) is caught.
8) is zero for each.
9) is nonzero, but the same for each case.
Answer: 3, 6
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