The law of conservation of momentum applies to a system of colliding objects only if:
A)there is no change in kinetic energy of the system
B)the coefficient of restitution is one
C)the coefficient of restitution is zero
D)the net external impulse is zero
E)the collisions are all elastic

Question

Quizplus · Accepted Answer

The law of conservation of momentum states that the momentum of a system of colliding objects is conserved if the net external impulse on the system is zero. Therefore, choice D is the correct answer. Choices A, B, and E are not necessarily true for the law of conservation of momentum to apply. While elastic collisions do conserve both momentum and kinetic energy, the law of conservation of momentum applies to all types of collisions, not just elastic ones. The coefficient of restitution is a measure of the relative velocity of objects after a collision, but it does not determine whether momentum is conserved.

The Law of Conservation of Momentum Applies to a System