Which of these is the best example of an elastic collision? A rubber ball is dropped from 1.2m and bounces back up to a height of 0.8m. A billiard ball strikes another of the same mass at rest and stops, and the second ball then moves with the same velocity as the first ball. A cart rams a similar cart and latches onto it with a loud clank. A cart rams another with a compressed spring, which is released, pushing them apart.