Dave Kreskowiak wrote:

BTW, did you notice the car barely moved at all as the sled was slamming into it??

It looks good doesn't it. The speed of the impact is faster that the speed of the shock traveling down the car. Basically there just isn't enough for the car to react to whats happening with it. You can replicate to the effect by putting two nails in each end of a broom handle, balancing the broom using the nails on two wine glasses. You can get a sword/axe/something sharp and chop the broom handle in two without breaking the glasses. The broom handle breaks before the force is transfered to the glasses. Joe