Car crash-completely inelastic collision?

[pebbles]

If a car crashed into a tree, or a head-on collision with another vehicle, the collision would be completely inelastic correct?
What would the kinetic energy be converted to? Internal energy?

 

[mgb_phys]

A head on with another same size vehicle could be fairly elastic - it depends on the speed and the angle.
Hitting a tree is pretty inelastic - although you might bounce back slightly.
The energy goes into deforming the crumple zone, creating free surfaces on broken parts and heating the compressed components.