A 75-kg man is standing in a 20-kg boat.The man steps to the right thinking he is stepping out onto the dock.However,the following will actually happen (ignore the friction of the water or air on the boat or the man):
A)The man only moves a short distance to the right while the boat moves a larger distance to the left.
B)The man only moves a short distance to the left while the boat moves a larger distance to the right.
C)The man actually stays still while the boat moves toward the left.
D)The boat doesn't move and the man moves to the right.
E)None of the above.

Question

A 75-kg man is standing in a 20-kg boat.The man steps to the right thinking he is stepping out onto the dock.However,the following will actually happen (ignore the friction of the water or air on the boat or the man):
A)The man only moves a short distance to the right while the boat moves a larger distance to the left.
B)The man only moves a short distance to the left while the boat moves a larger distance to the right.
C)The man actually stays still while the boat moves toward the left.
D)The boat doesn't move and the man moves to the right.
E)​None of the above.

Quizplus · Accepted Answer

When the man steps to the right, due to the conservation of momentum, the boat will move to the left. Since the boat is lighter than the man, it will move a larger distance compared to the distance the man moves to the right.

A 75-Kg Man Is Standing in a 20-Kg Boat