Each time a ball bounces, it loses e.g. 40% of its vertical kinetic energy. Can you describe what happens to the ball?
(Clarification for the pedantic: the ground is flat, and each part of the ball’s path is a parabolic arc. Don’t consider friction, atoms, relativity, quantum, etc! Just describe qualitatively what happens to the ball. There’s no need for calculations or numbers, although they might help support your reasoning. You will likely need some knowledge of physics and math.)
I invented this little puzzle and I know the answer. I’ve asked people to solve it, and no one has ever given me the right answer. So, just for fun, I’m offering a $50 prize for the first person who can answer it correctly before Monday 15th November, and I will be pleased to meet you! I can send you the prize by PayPal, or in person if you live in Melbourne. It’s a nice puzzle; the answer is surprising and interesting.