How do Seatbelts and Airbags protect you during a crash?

Credit image: public image
Credit image: public image

Article by: Abhinav Tanksale, on 01 June 2022, at 08:50 am PDT

Seat belts are a vital part of a car. They help keep the driver, the front-seat passenger, and the rear-seat passengers safe and secure in the case of a collision. But here's the thing: not everyone uses them. In fact, a shocking number of drivers and passengers go about their daily lives without buckling up at all. This blog will focus on a simplified explanation of what exactly happens during a car crash and how using a seat belt is a good practice. 

Credit image: public image
Credit image: public image

Each year, hundreds of thousands of people die in traffic accidents. The severity and frequency of these fatal collisions has led to laws requiring the use of seat belts or other restraints for the safety of motorized vehicle passengers. In most cases, improper usage of a seat belt is malpractice resulting from ignorance or neglect on the part of motorists who fail to understand its nature and purpose.

Car crashes can be fast and intense. One might be surprised to know that car crashes have the potential of reaching up to 60 g during an accident without even buckling your seatbelt. According to the National Highway Traffic Safety Administration, wearing a seatbelt can reduce their chances of dying in a car accident by 45% and reduce their risk of injury by 50%.

The reason behind this remains inconclusive but many believe that it is because of the impact factor. The impact factor is what we also refer to as force when dealing with collisions. To derive the impact force equation, you can consider the law of conservation of energy. We know, in the beginning, a moving object possesses kinetic energy that reduces to zero after the collision.

 To fulfill the law of conservation of energy, one must compensate for the change in kinetic energy which we express with the impact force equation: 

F = m * v² / (2 * d)

F is the average impact force, m is the mass of an object, v is the initial speed of the object & d is the distance traveled during a collision.

What is even more surprising is that extending the distance you travel or are capable of traveling during a collision actually reduces the average amount of impact force exerted on an object during a said collision. In other words, a longer distance traveled equals less impact force ultimately resulting in fewer injuries sustained by either party (as well as less damage done to your vehicle).

What's highly dangerous for a human being is the change in velocity caused by acceleration or deceleration at that specific moment. This means if one undergoes a sudden increase in velocity while moving a certain distance, he/she must do enough work to slow oneself down back to your original speed again.

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