According to the Newton's First Law, a moving object will continue moving in a straight line unless external force acted on it. As a result, if you are sitting on braking car, you will keep on moving and been thrown out of the seat due to inertia effect.
Impulsive force is produced during collision according to the Newton's Second Law. If time of impact is reduced, the greater the impulsive force produced causing severe damage to the car.
In making a car safer to drive, engineers have to overcome these two factors that are inertia effect and impulsive force. Here are some safety features incorporated in a car:
- Safety belt - help to hold the passengers in their position during collision to prevent them from being thrown forward due to inertia.
- Front and rear crumple zone - easily crushed to increase the time of impact.
- Shatter-proof windscreen - it will not break into pieces easily.
- Airbags - to increase the time of impact and to cushion the driver from being hitting the front of the car.
- Passenger safety case - reinforced to protect passenger.
- Collapsible steering - to increase the time of collision if the driver crashes against it.
- ABS braking system - to prevent the car from skidding if sudden brake is applied.
- Headrests - prevent the passengers from suffering severe neck injury.
- Padded dashboard - increases time interval of collision so that impulsive force is reduced.