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##### Question: 1

Explain law of conservation of momentum? Also drive its formula?

##### Answer: 1

1-23The momentum of an isolated system of two or more than two or more than two interacting bodies remain constant.we can write it as,Total momentum of gun and bullet before fixing =0let m be the mass of the bullet and v be its velocity on firing the gun; M be the mass of the gun and V is the Velocity with which it recoids . thus the total momentum of the gun is fired will be: The momentum of the gun and the bullet after the gun is fired = Mv+ mv Total momentum before firing = Total momentum after firing Mv =-mv or v=-m/M v

An isolated system is a group of interacting bodies on which no external force is acting . IF no unbalanced on net force acts on a system then its momentum remains constant.

Consider a system of gun and a bullet. Before firing, the Velocity of the bullets as well as that of gun was zero. therefore the total momentum of both the objects was also zero.

When the gun is fired bullet shoots out of guns and acquire momentum. To converse momentum the qun recoils backward. Now according to the law of conversation of momentum, the total momentum of the gun and bullet will also be zero after the gun is fired.

According to the law of conversation of momentum.

MV + mv =0