Car accident.?

Question

I have some data dealing with deformation in a crash test and am compairing it with a real life situation. I have the speed of the vehicle in the crash test and the resulting deformation. I also have the information realting to the deformation on the car durring the "real" situation.

There must be some formula that I am missing...... can someone poke me in the right direction?

Does it matter that in the real crash there is deformation to both cars?

I am thinking that there is something with work and energy...... springs and kinetic energy..... but I am unsure.

We are assuming alot here:
-flat ground
-linear impact.............. ect

Answer 1

I don't have any equations for you, but consider this...

In an inelastic collision, kinetic energy is NOT conserved!! In the case of deformation, that is even more true. Assuming flat ground, there is no change in PE, so all the energy comes from KE.

Deforming the car takes energy. The only source is KE. So you must consider the work done in deforming the car.

You may be reasonable in assuming a constant force during the impact. You can get this through impulse/momentum changes. You can then find the work done by determing what distance the force acted on, and evaluating

W = ∫F∙dx

Furthermore, momentum is ALWAYS conserved in collisions, so you can check to make sure your work calculation is correct.

If you need any more info during your project, I'd be happy to help. Check my profile to e-mail me or IM me.