During a collision with a wall, the velocity of a 0.200-kg ball changes from 20.0 m/s toward the wall to 12.0 m/s away from the wall. If the time the ball was in contact with the wall was 60.0 ms, what was the magnitude of the average force applied to the ball?
A) 40.0 N
B) 107 N
C) 16.7 N
D) 26.7 N
E) 13.3 N

Question

Quizplus · Accepted Answer

Using the impulse-momentum theorem, we can find the average force applied to the ball:

Impulse = Δmomentum

J = Δp = mΔv

J = 0.200 kg × (12.0 m/s - (-20.0 m/s))
J = 6.4 kg·m/s

The average force is then:

F = J/Δt

F = 6.4 kg·m/s / 0.06 s
F = 107 N

Therefore, the best choice is B, as it corresponds to the magnitude of the average force applied to the ball during the collision.

During a Collision with a Wall, the Velocity of a 0.200-Kg