# Energy changes in falling bodies [duplicate]

Consider these four situations:

1. a tennis ball falling on a wooden floor
2. a tomato falling on a wooden floor
3. a book falling on a wooden floor
4. a tennis ball falling on a soft mattress Why only in the first situation the object bounces?
• In the case of the tennis ball on the wooden floor the collision is elastic, and in the others the collision is inelastic. The tennis ball will flex, and push itself up. The tomato will flex but lacks elasticity to propel it back up. Commented Jun 22, 2023 at 19:01
• @user16217248 thanks, but what does the kinetic energy of the object in each situation change into? Commented Jun 22, 2023 at 19:21
• Ball: Back into the ball, as upwards velocity. Tomato: If the tomato ruptures, sideways velocity of the tomato pieces. Book: Sound. Tennis ball on mattress: Infrasound I am guessing. Commented Jun 22, 2023 at 19:28
• Does this answer your question? Why the rubber ball bounced higher than the glass ball? Commented Jun 22, 2023 at 19:48
• @user16217248 thanks, in case of a mattress I assumed it would be the elastic energy of the mattress and then it would transform into heat Commented Jun 22, 2023 at 19:55