Information
Gail placed two carts on a track. Both carts have very low friction. A spring is attached to one of the carts. Gail compressed the spring between the two carts. Then, she released the carts. The two carts pushed apart.
Question
Which statement explains why momentum is conserved in this situation?
Answer options with 4 options
A.
The two carts have zero initial momentum.
B.
The net force acting on the system is zero.
C.
The initial momentum of the spring is zero.
D.
The two carts move at the same speed in opposite directions.
1 answer
The correct answer is:
B. The net force acting on the system is zero.
This is because when no external forces are acting on a system, the total momentum of that system remains constant. Since Gail's experiment involves two carts with very low friction and no external forces acting on them, the momentum is conserved.
