A 0.6 kg ball experiences a total impulse of 3.6 N·s during a collision lasting 0.02 s. What is the average impact force?

A 0.6 kg ball experiences a total impulse of 3.6 N·s during a collision lasting 0.02 s. What is the average impact force?

• A. 180 N
• B. 9 N
• C. 1800 N
• D. 36 N

Answer: (A)

The key idea is that impulse equals the average force times the collision time, and also equals the change in momentum. Here the impulse is 3.6 N·s and the contact time is 0.02 s, so the average force is F_avg = impulse / time = 3.6 / 0.02 = 180 N. The mass isn’t needed for this calculation because the given impulse already represents the momentum change. A shorter collision with the same impulse would require a larger force, while a longer collision would need a smaller force.

The key idea is that impulse equals the average force times the collision time, and also equals the change in momentum. Here the impulse is 3.6 N·s and the contact time is 0.02 s, so the average force is F_avg = impulse / time = 3.6 / 0.02 = 180 N. The mass isn’t needed for this calculation because the given impulse already represents the momentum change.

A shorter collision with the same impulse would require a larger force, while a longer collision would need a smaller force.