Question

Discuss the law of conservation of momentum.

Answer 1

If the net external force acting on a system of bodies is zero, then the momentum of the system remains constant. This is the basic principle of conservation of linear momentum. Notice that momentum of the system is conserved and not that of the individual particles. Momentum of the individual bodies in the system might increase or decrease according to the situation, but the momentum of the system will always be conserved, as long as there is no external net force acting on it.