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Comparing the bounce of smooth balls and rubber super-balls. First a smooth metal ball is thrown without rotation toward a parallel set of surfaces (floor and ceiling). The smooth metal ball acquires a slight clockwise rotation, but continues with its forward motion and bounces from floor and ceiling, moving to the right. A ping pong ball entering at an angle from the left bounces from both surfaces, but stops its forward motion and ends up bouncing vertically up and down. However, when a superball enters f
