In the absence of any external force, the total momentum of a system stays the same is the law of conservation of momentum.
The law of conservation of momentum state that in an isolated system, the total mass of objects does not change which means that the mass of objects before collision is equal to the total mass after collision.
The formula for law of conservation of momentum is. M1V1 + M2v2 = M1V1 + M2V2
M1 is initial mass of objects
V1 initial velocity of the object.
M2 is final mass
V2 final velocity.
Therefore, In the absence of any external force, the total momentum of a system stays the same is the law of conservation momentum.
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