When a pair of isolated objects collides:
The sum of the impulses on the system is non-zero.
The impulse on one object is the same as the impulse on the other object.
The change in speed of one object is equal but opposite to the change in speed of the other object.
Each object will experience an impulse, but these impulses will cause equal but opposite changes in the objects’ momenta.
Whichever object started with more momentum will continue to have more momentum.
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