Why do cars have crumple zones?

Crumple zones are designed to absorb the impact energy of a collision, thereby reducing the force transferred to the vehicle occupants. In a car crash, the crumple zone collapses and absorbs the energy of the impact, which slows down the vehicle and reduces the impact forces on the passengers. This energy absorption helps to reduce the risk of serious or fatal injuries to the occupants by reducing the deceleration forces experienced by their bodies.

Here are some additional benefits of crumple zones:

- They help to distribute the impact forces over a larger area of the vehicle, reducing the amount of force concentrated on any one area.

- They can help to prevent the car from rolling over, which can cause additional injuries to the occupants.

- They can help to mitigate the damage to vehicle components other than the crumple zone itself.

- Crumple zones have been mandated by governments globally and have significantly contributed to the improved safety performance of modern vehicles in crash tests and real-world accidents.

Crumple zones are specifically designed areas made of weaker materials and collapsible structures with predetermined weak points at the front and sometimes the rear of a vehicle. During a collision, these designated weaker components deform and crush at a controlled rate of compression. This controlled yielding allows for energy absorption in the designated region and gradually decelerates the car. By deforming and absorbing this crash energy, crumple zones help to create a "cushion" for those inside the vehicle and reduce the intensity of the sudden change in speed.