Question

state the law of conservation of momentum and derive its expression

Answer 1

The mass of two bodies are m1 and m2 Initial velocity of two bodies are u1 and u2 Final velocity of both the bodies are v1 and v2 Acceleration=a1 and a2 respectively Firstly two bodies moving with initial velocity Then when collision took place they apply equal and opposite force so the force becomes F1 and F2 After collision they started moving with the final velocity FIRST BODY Initial velocity = u1 Final velocity = v1 a1=(v1-u1)/t F1=m1(v1-v2)/t SECOND BODY a2=(v2-u2)/t F2=m2(v2-u2)/t F1=-F2 m1(v1-u1)/t= -m2(v2-u2)/t m1v1-m1u1=m2v2+m2u2 m1v1+m2v2=m1u1+m2u2 Total momentum after collision = Total momentum before collision According to conservation of momentum , momentum can neither be created nor be destroyed........

Answer 2

Newton's third law states that for a force applied by an object A on object B, object B exerts back an equal force in magnitude, but opposite in direction. This idea was used by Newton to derive the law of conservation of momentum. ... B=m_{2}(v_{2}-u_{2}) (change in momentum of particle B)