(b) Which of the following must be true for the sum of the magnitudes of the momenta of the individual particles in the system?

Options

A. It must be zero
B. It could be non-zero, but it must be constant
C. It could be non-zero, and it might not be constant
D. It could be zero, even if the magnitude of the total momentum is not zero

Answer

C

Explanation

(b) Individual particles feel external force which is internal force for whole body.
i.e. Momentum of individual particle is not conserved so it will very.