A 20-g bullet moving at 1 000 m/s is fired through a one-kg block of wood emerging at a speed of 100 m/s. If the block had been originally at rest and is free to move, what is its resulting speed?
A: 9 m/s
B: 18 m/s
C: 90 m/s
D: 900 m/s
E: 60 m/s
F: 600 m/s
A: 9 m/s
B: 18 m/s
C: 90 m/s
D: 900 m/s
E: 60 m/s
F: 600 m/s
举一反三
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