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*23.  The
lead female character in the movie Diamonds Are Forever is standing at the edge of an offshore oil
rig. As she fires a gun, she is driven back
over the edge and into the sea. Suppose the mass of a bullet is 0.010 kg and
its velocity is +720 m/s. Her mass (including the gun) is 51 kg. (a)
What recoil velocity does she acquire in response to a single shot from a
stationary position, assuming that no external force keeps her in place? (b)
Under the same assumption, what would be her recoil velocity if, instead, she
shoots a blank cartridge that ejects a mass of 5.0 x 10-4 kg at a velocity of +720 m/s?
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Consider
the character, the gun and the bullet to be a single system. Initially all are at rest. After she fires the gun, she and the gun go
in the direction opposite to the bullet.
The forces propelling the bullet and recoiling the gun are internal to
the system so momentum is conserved.
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