By changing an object’s momentum, we are able to move it either faster or slower, and eventually to a halt, depending on the amount, direction, and magnitude of the force that acts upon the object. By applying this aspect on a car’s safety systems, we are able to either reduce the risks of injuries as the results of a crash, or to avoid a crash completely. It is with this principle that seatbelts, crumple zones, air bags, and braking systems, among other features, are able to save us from such unfortunate events.
Seatbelt – an active safety feature
In America alone, seatbelts have saved an approximate of 13,000 lives each year. Furthermore, an estimate of 7,000 fatalities could have been helped if the passenger had worn a seatbelt during the event of the crash. Although at times wearing a seatbelt during a drive could result in seatbelt-caused injuries likely around the sternum area and perhaps even death, the risk of going without far outweighs the risk of the injuries caused by the seatbelts.
By the law of inertia, when a car crashes (i.e. decelerates rapidly) the passenger will continue to move at the same speed until a force acts upon them to cause deceleration. There is a stopping force. If said passenger flies out the windshield onto the tarmac, the windshield would apply considerable force upon passenger’s head (Newton’s second law), and would cause death or injury, and the tarmac would then apply more force to the body. A seatbelt spreads force to the less vulnerable sections of the body, and in a longer space of time because of its flexible material (compared to the sturdy windshield).
Since the belt applies force on a wide range of the body, less pressure would be involved, and the passenger would experience less pain. The seatbelts are also designed to stop the passenger from moving forward too much in the event of a collision, because this may let the passenger collide with the wheel instead.
By having more