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Conservation of momentum (7-14)

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Question 1 of 2

Question

If the net external force on a system of objects is zero...then the total momentum of the system at the end of a time interval...
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Review

We now have the answer to the question “When is momentum conserved?” Equation 7-13 says that the total momentum does not change over the time interval Δt if the net external force on the system is zero. Then the left-hand side of Equation 7-13 is zero, and so there is zero difference between the final total momentum →Pf=→pAf+→pBf and the initial total momentum →Pi=→pAi+→pBi.