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2 years ago

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A 23 g bullet traveling at 230 m/s penetrates a 2.0 kg block of wood and emerges cleanly at 170 m/s. If the block is stationary

on a surface with a coefficient of kinetic friction of 0.15 when hit, how far does it move after the bullet emerges?

1 answer:

Anuta_ua [19.1K]2 years ago

6 0

Answer:

Explanation:

Conservation of momentum during the collision

0.023(230) + 2.0(0.0) = 0.023(170) + 2.0v

v = 0.69 m/s

The initial block kinetic energy will be converted to friction work

½mv² = Fd = μmgd

½(2.0)(0.69²) = 0.15(2.0)(9.8)d

d = 0.1619387... m

d = 16 cm

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