A student's life was saved in an automobile accident because an airbag expanded in front of his head. If the car had not been equipped with an airbag, the windshield would have stopped the motion of his head in a much shorter time. Compared to the windshield, the airbag:

Explanation

The correct answer is Option D: Exerts a much smaller force. When a collision occurs, the airbag extends the time it takes for the head to come to a stop, which decreases the average force experienced by the student. Although the momentum change (△p) and impulse remain the same with or without an airbag, the airbag reduces the force by increasing the time interval (△t) during which the momentum change occurs. Therefore, the force is smaller with an airbag. Option A is incorrect because the change in momentum remains consistent between scenarios. Option B is incorrect as the impulse does not change; it's the force applied over time that differs. Option C is incorrect because the change in kinetic energy depends on changes in velocity, which are the same in both cases.