Two skaters at rest, one of 100 kg and the second of 50 kg, push off against one another. The total momentum of the system after they push off is
A) positive.
B) zero.
C) negative.
D) increasing as the skaters move away from each other.
E) decreasing as the skaters move away from each other.

Question

Quizplus · Accepted Answer

The total momentum of the system remains zero after the skaters push off against each other due to the conservation of momentum. Initially, both skaters are at rest, so the total initial momentum is zero. When they push off, they exert equal and opposite forces on each other, leading to equal and opposite changes in momentum, which keeps the total momentum of the system at zero.

Two Skaters at Rest, One of 100 Kg and the Second