Question

When a baseball player catches a baseball, the glove "gives" or moves backward. How does this movement affect the change in momentum of the baseball?

The change in momentum increases because the impact time increases.
The change in momentum decreases because the force decreases.
The change in momentum stays the same because the ball still comes to a stop.
The change in momentum depends on the initial speed of the ball and the time to stop.

Answer 1

The change in momentum stays the same because the ball still comes to a stop.

Reason: Δp = m(v_final − v_initial). If the glove brings the ball to rest (v_final = 0), Δp = −m v_initial regardless of how long the stop takes. Moving the glove backward increases the contact time and therefore reduces the average force (J = F_avg Δt), but it does not change the total impulse (change in momentum) required to stop the ball.