What makes a trampoline bounce?

Answer 1

This is due to the elastic properties of the polymer that makes up the ball.

As the ball hits the surface, it compresses under strain (but only to a certain point). The residual strength of the structure of the ball eventually overcomes the initial downward force to spring back to it normal shape. This causes the ball to rebound from the surface.

It will not bounce as high as the start point as energy is lost into to sound and heat.

Answer 2

The surface of a trampoline can be one of a few different types. Personal or Home-use trampolines are usually equipped with a polyester bed which is black and made of soft, synthetic material. Other surfaces are webbing and string type beds. These surfaces are more flexible and resilient than the poly bed and used in specific training and competitive uses. In addition to the bed surface, the trampoline also uses springs that suspend the bed from the 4-sides of the trampoline frame. Depending on the weight of the person, the trampoline bed itself flexes and also causes the springs to stretch downward. As the bed rebounds from the initial contact, the user is propelled into the air. The heavier the person, the higher the trampoline can propel them into the air. Also, the higher the user bounces the further the bed and springs are deflected and the higher the next bounce will be. Trampoline can be lots of fun, but because it seems to easy to use it is very often underestimated in terms of the danger the user is exposed to when bouncing on a trampoline. There are certain basic safety guidelines that must be followed in order to maximize the safety of the user. There should only be one person at a time bouncing on the bed of the trampoline. This is because in the event that one user is on the way up and another coming down, a collision is likely. Also, there is a situation that arises when more than one person bounces on the trampoline that is referred to as "kipping" in the gymnastics and trampoline industries. If a person jumps on the trampoline bed just as a performer is making contact downward from a jump, then that person adds their body weight and the bed and springs are deflected much further down that normal and one or both of the bouncers will be propelled much higher into the air as a result. This particular activity is very dangerous and should not be allowed in any setting, home or at a gymnastics or other professional instruction setting. The first thing we teach young kids about the trampoline is how to stop bouncing. This is vital to the safety of the participant, especially young children. To stop the bounce the user only needs to bend their knees and let the trampoline bed rise up under them without propelling them upward. Once the student can step the bounce they are ready to begin learning very basic bounces and other skills. The next most important guideline is that the user must make every effort to remain in the center of the trampoline at all times. If a student leaves the center of the trampoline they are instructed to bend their knees and stop bouncing immediately. If a user continues to bounce after they are off-balance they may find themselves falling in an upside down position on the trampoline bed or they may even be propelled off the trampoline entirely. In the event the student lands upside down or drastically off-balance, serious injury can occur. There is much more to maintaining proper safety precautions on a trampoline than most people realize. Have fun bouncing, but remain safe at all times.