If passengers in a car do not wear their seat belts and the car is brought to a sudden and abrupt halt due to a collision or a sudden stop, several things can happen to the passengers:
Inertia: Objects in motion tend to stay in motion, and objects at rest tend to stay at rest unless acted upon by an external force (Newton's First Law of Motion). When a car suddenly stops, the passengers inside the car will continue moving forward at the car's original speed. Without seat belts, they may be thrown forward.
Ejection: Passengers not wearing seat belts can be ejected from the vehicle through the windshield, side windows, or open doors, depending on the nature of the collision. This can result in serious injury or death.
Collision with Interior: Passengers who are not restrained can collide with various parts of the car's interior, such as the dashboard, windshield, or even with other passengers. These collisions can cause severe injuries.
Secondary Collisions: In the event of a collision, the car may not come to a complete stop immediately. It might bounce or continue to move for a short distance after the initial impact, causing passengers to experience additional impacts.
Whiplash: When the car suddenly stops, the head and neck of passengers can snap forward and backward rapidly, causing whiplash injuries.
Seat belts are crucial safety devices designed to mitigate these risks. They keep passengers restrained in their seats during a sudden stop or collision, spreading the deceleration forces over a longer period, reducing the risk of injury, and preventing ejection from the vehicle.
In summary, not wearing seat belts in a moving vehicle increases the likelihood of severe injury or even death in the event of a sudden stop or collision. It is essential for all passengers to wear their seat belts at all times when inside a moving vehicle to protect their safety.