Question

when a cannonball is fired from a cannon, the momentum of the recoiling cannon is momentarily ______. view available hint(s) ○ less than the momentum of the fired cannonball ○ greater than the momentum of the fired cannonball ○ equal and opposite to the momentum of the fired cannonball ○ the same as that of the fired cannonball submit

Explanation:

This question is about the law of conservation of momentum. In a system (cannon + cannonball) with no external net force (initially at rest, so total initial momentum is 0), when the cannonball is fired, the total final momentum must also be 0. Let the momentum of the cannonball be \( \vec{p}_{ball} \) and the momentum of the cannon be \( \vec{p}_{cannon} \). Then \( \vec{p}_{ball} + \vec{p}_{cannon} = 0 \), so \( \vec{p}_{cannon}=-\vec{p}_{ball} \), meaning they are equal in magnitude and opposite in direction.

Answer:

C. equal and opposite to the momentum of the fired cannonball