The purpose of the seat belt is to hold the passenger in place so the passenger is almost part of the car which prevents the passenger from flying forward as the car stops abruptly in the case of a collision.
Real Life Situation
When a car stops suddenly due to a collision with another object such as another car, a tree, pole etc. the car’s acceleration decreases very quickly in a short period of time. This is called deceleration. Newton’s Law of Inertia explains how this happens.
An object in motion continues in motion with the same speed and direction unless acted upon by an unbalanced force.
- As the car collides with another object, the other object provides the force which changes the speed and direction. The car stops going in the direction it was going in, and in some cases bounces back depending how hard of a force hits it or how much momentum the car had. Also, the speed decelerates quickly due to the impact.
- When all this happens the passenger is not being acted upon by a force to slow them down. This part is where the seat-belt comes into play.
- As the person continues in their same direction and speed (forward and the same speed that the car was going) the seat-belt catches them, holding them back from flying through the air.
- The alternative is to not wear a seat-belt, but a force will still have to act on the person in order to slow them down. This force will come from the dashboard or windshield as the person crashes into it causing a lot of damage to themselves.
- A seat-belt has two parts. The first part rests over the passengers’ pelvis and the second part rests over the shoulder and across the chest. When the car stops abruptly the seat-belt applies the stopping force across a large section of the body so the damage is reduced.
- Seat belts are made flexible to provide the seated occupant the convenience of some free movement of the upper torso within the compartment, while providing a method of limiting this movement in the event of a crash.
- Since seat-belts are flexible one might ask how do they hold you in place? Seat-belts are designed so that the machinery behind them tightens up the belt to hold the passenger in place when the car decelerates quickly.
- Air bags are much more effective when the driver and passengers are wearing their seat belts. If you’re not wearing your seat belt, then your body will most likely not remain in the position in which the airbag can protect you.
Related: Vehicle Safety: Past vs Present
You must understand that there are plenty of reasons to wear a seat belt. The seat belt serves to protect drivers and passengers from injury during any type of collision. They ensure that the strongest part of the body is restrained and the impact of the crash is spread out over a wider area, including the shoulders and torso. With a seat-belt on, your spinal cord as well as the brain is pretty much protected. Buckle up & always wear seat belts!
Lastly, have a look at the award winning road safety advert to help you realize the importance of wearing seat belts.
A 3d animation professional with over 20 years of industry experience having served in leading organizations & production facilities of Pakistan, an avid car enthusiast and petrolhead with an affection to deliver writings to help shape opinions. Formerly written for PakWheels as well as major publications including Dawn. Founder of CarSpiritPK.com