Question

a small rock bounces off the windshield of a moving car and experiences a large change in velocity. how does the car’s momentum change? (1 point) it has a change in momentum greater than that of the rock, in the opposite direction. it has a much smaller change in momentum than that of the rock, in the opposite direction. it has a change in momentum equal to that of the rock, in the opposite direction. it does not change.

Explanation:

According to the law of conservation of momentum, in an interaction (like the rock hitting the car's windshield), the total momentum before and after remains constant. So the change in momentum of the car ($\Delta p_{car}$) and the change in momentum of the rock ($\Delta p_{rock}$) must satisfy $\Delta p_{car}=-\Delta p_{rock}$. The negative sign indicates opposite directions, and the magnitudes are equal. So the car's momentum change is equal in magnitude to the rock's, opposite in direction.

Answer:

It has a change in momentum equal to that of the rock, in the opposite direction.