Two people, one twice as massive as the other, attempt a tug-of-war with 12 meters of rope on frictionless ice. After a brief time, they meet. The heavier person slides a distance of
A)3 m.
B)4 m.
C)6 m.
D)0 m.

Question

Quizplus · Accepted Answer

Since the system is on frictionless ice and momentum must be conserved, the center of mass of the system does not move. The rope is 12 meters long, so the center is 6 meters from each end. Since they meet at the center of mass, and the system started with the center of mass at the midpoint of the rope, each person moves half the distance to the center, which is 6 meters. However, because one person is twice as massive as the other, they will move less to conserve momentum, specifically half the distance, resulting in the heavier person moving 4 meters.

Two People, One Twice as Massive as the Other, Attempt