Question

what is Momentum first law

Answer 1

The momentum of a body is constant if no external unbalanced force is acting on it.   (By Newton's first law, a body remains in the state of rest or the state of uniform motion unless an external unbalanced force acts on it)  HOPE IT HELPS! ^_^  

Answer 2

Conservation of momentum is a fundamental law of physics which states that the momentum of a system is constant if there are no external forces acting on the system. It is embodied in Newton's first law (thelaw of inertia).

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