Question

two cars collide and come to a complete stop. where did all of their energy go?

Answer 1

into the atmosphere, mainly in the form of heat and sound

Answer 2

and the damage of the automobiles

Answer 3

Their energy mostly went into the buckling of the cars and the actual stopping of the cars. There's also some heat and sound dissipated as well but not nearly as much energy is dissipated there.

Answer 4

Yeah, energy dissipation in automobile damage and car insurance rate hikes.

Newton did that stuff, guys. Remember?

Answer 5

energy that deforms an object in a collision is mostly transformed into heat through internal friction
http://www.physicsforums.com/showthread.php?t=163624

Answer 6

Is this something I'll learn in statistical mechanics?

Answer 7

energy is yes lost due to the fact that the cars are going in opposite direction and stopping eachother but wouldnt this energy ultimately end up in the forging of the metals into new shapes, densities, etc?

Answer 8

Energy is used to transform the shape of the object, but when all is said and done the object is not more energetic just for being all twisted up. By conservation of energy it must therefor go into the atmosphere, since it does not stay in the object itself.

Answer 9

boom sound,friction in the road that helped them to stop after colliding otherwise they go on accelerating forever