A man is marooned at rest on level frictionless ice. In desperation, he hurls his shoe to the right at 15 m/s. If the man weighs 720 N and the shoe weighs 4.0 N, the man moves to the left at approximately: A) 0 B) 2.1 * 10^-² m/s C) 8.3* 10^-² m/s D) 15 m/s E) 2.7 * 10^-³ m/s

Question

Quizplus · Accepted Answer

According to conservation of momentum, the momentum of the man and the shoe before the throw is zero. After the throw, the total momentum of the system is still zero since there are no external forces acting on the system. Therefore, the momentum of the man and the shoe after the throw must be equal in magnitude and opposite in direction.

Let the velocity of the man after the throw be v. Then, using conservation of momentum:

(720 N)(0 m/s) + (4.0 N)(15 m/s) = (720 N + 4.0 N)(-v)

Solving for v, we get:

v = 8.3 m/s

Since the velocity is negative, the man moves to the left. Therefore, the answer is choice C.

A Man Is Marooned at Rest on Level Frictionless Ice