Question

define law of conservation of momentum and prove that the momentum of body is conserved ​

Answer 1

Law of conservation of momentum states that total momentum of system remains conserved in the absence of external force. Proof: Consider a body of mass m1 moving with velocity U1, striking against another body of mass m2 moving with velocity U2. ... Let v1 and v2 be the velcoities of two bodies after collision.

Answer 2

If not Torque Act on the body then the angular momentum of the body is conserved