Final answer:
The correct answer is that padded dashboards increase the time of impact in a collision, which reduces the force felt by occupants, helping to prevent severe injuries.
Step-by-step explanation:
The correct answer is option b) increase the time of impact in a collision. Padded dashboards are used in cars to reduce the force experienced by the occupants during a collision.
The concept of impulse, which is the product of the net force and the time over which the force acts, tells us that if we increase the time over which the collision occurs, the force of impact will be reduced.
This is because the change in momentum (impulse) is constant, and spreading this change over a longer duration decreases the force.
For example, airbags and padded dashboards increase the time of impact, hence the force felt by passengers is significantly less, which can prevent severe injuries. Similarly, parts of a car that can crumple increase the collision time, further reducing the force of the impact on the occupants.
The correct answer is option a) decrease the impulse in a collision.
Padding on dashboards in cars is used to decrease the force of impact in a collision. When a collision occurs, the padding on the dashboard increases the time over which the force acts.
This means that the force of impact is spread out over a longer duration, which reduces the overall force experienced by the occupants of the car. By reducing the force of impact, padded dashboards help protect the passengers and decrease the chance of injury.