Transcription: Conservation of momentum is a consequence of Newton's third law. Consider a flying projectile that explodes into several pieces, like this multiple warhead missile. The forces between the pieces we call internal forces. There may also be external forces such as gravity. By Newton's third law, the internal forces act in equal but opposite pairs. Any force on one piece is offset by an equal and opposite force on another piece. These forces are balanced, i.e., add to zero. Therefore, the internal forces can produce no net change in momentum. Explosions can serve momentum. The same argument holds ...
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