Question

The momentum of an isolated system remains conserved provided:
a) Net final momentum of the system is zero.
b) Net external force of the system is non zero.
c) Net initial momentum of the system is zero.
d) Net external force on the system is zero.​

Answer 1

Answer:

The momentum of an isolated system of particles is conserved. The forces are internal in nature and sums up to zero for entire system. As the external force is zero on system it's momentum remains conserved.

Answer 2

Answer:

d) Net external force on the system is zero.​