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
发布时间：2025-05-24 16:52:48
