Research:physics behind car crumple zones

[Harold]

I'm doing a research essay on the physics behind car crumple zones,

I just need a little bit of assistance in what it involves, I've looked at impulse and workdone and understand how the c.zone works in trying to minimalise these. What i don't understand is how these forces(if that's what they are)actually affect and injure the passengers inside the car.

Any assistance would be great, also if there's any aspects I'm not looking at I'd be very grateful for advice.

thanks

 

[Astronuc]

The crumble zone in a car increases the time over which the decelerations are applied to the passenger compartment. For a given initial momentum, the applied forces (decelerations) are greater, the shorter the time. The crumple zone dissipates the energy in a collision, rather than the passenger.

The crumple zone are composed of ductile materials, e.g. HSLA steels and plastics. The majority of the structure is steel with a large plastic range (large strain without failure).

Injury of a passenger occurs if the passenger strikes a hard surface in the passenger compartment, e.g. steering wheel, dashboard, or door, roof, or other part of car frame. In addition to fractured bones, and blunt trauma, internal organs and blood vessels can tear if they experience too high an acceleration.

 

[thepatientmental]

Crumple zones in cars are designed to absorb and dissipate the kinetic energy during a collision, thereby reducing the impact force on the passengers inside the car. This is achieved through the principles of impulse and work done.

Impulse is the product of force and time, and it is directly related to the change in momentum. In a car crash, the crumple zone extends the time of impact, thus reducing the force experienced by the passengers. This is because the force is spread out over a longer period of time, resulting in a lower impact force.

Work done is the product of force and distance, and it is related to the energy absorbed during a collision. In a car with crumple zones, the front end of the car is designed to crumple and absorb the energy, rather than transferring it directly to the passengers. This reduces the potential for injuries to the passengers.

In addition to these principles, car manufacturers also use materials with specific properties in the design of crumple zones. These materials are selected for their ability to deform and absorb energy, such as aluminum, steel, and plastic. The placement and structure of the crumple zones are also carefully designed to distribute the impact force and protect the passenger compartment.

It is important to note that while crumple zones help reduce the impact force on passengers, they do not completely eliminate the risk of injuries. The severity of injuries also depends on factors such as the speed of the car, the angle of impact, and the use of safety devices like seatbelts and airbags.

In conclusion, the physics behind car crumple zones involves understanding the principles of impulse and work done, as well as the materials and design used to absorb and dissipate energy during a collision. It is an important aspect of car safety that helps protect the passengers inside the car. I hope this helps with your research essay. Good luck!