Why are Trampolines Bouncy? Physics Can Explain!

Have you ever been on a trampoline? Have you ever felt your feet hit its fabric and get lifted into the air? It is quite the experience! But have you ever wondered what makes a trampoline bounce? No ordinary fabric could launch a person several feet in the air with one bounce. So, what makes a trampoline bounce?

If you have not been on a trampoline, you have at least seen one. A person simply has to jump on the trampolines surface. However, there is some science to it. The science is called the trampoline effect, and it follows a law of physics. Most people believe that it is the fabric that launches you into the air, but actually, it is the system of springs attached to the fabric.

When you jump on a trampoline, your weight forces the springs to coil downwards. This kinetic energy of jumping is applied to the springs, forcing the trampoline downward. As a result of the springs having pressure, or kinetic energy exerted on it, Hooke’s Law is applied. Robert Hooke was a 17th-century physicist who studied the actions and reactions of elastic properties. In his law, he states that “the force needed to extend or compress a spring by some distance scales linearly with respect to that distance.” What Hooke means is that depending on the force you exert on a spring, you will receive the same distance or length of pushback returned. Essentially saying that the harder you jump on a trampoline, the higher you will bounce due to the springs reacting to your applied force. This law has many similarities to Newton’s third law which states, “with every action, there is an equal and opposite reaction.” However, Hooke’s Law is concerned with the responses of elastic objects, and theory is contingent on the stiffness of the spring. If the spring is stiff, or more solid, you won’t have very much pushback. Though Hooke’s theory is correct and is used in many different fields of science and engineering, the principle has stipulations.

Hooke’s theory only works on elastic bodies such as trampolines, rubber products, and latex. For the most part, only elastic objects can exert the same amount of energy back once energy has been transferred to it. However, there are small exceptions to this rule. For example, some solid objects will also return applied force, but only in small amounts. If too much force is applied to a solid object, it will physically break or “change.”

Hooke’s theory also has a limit of how much energy can be applied to an elastic body. In the example of a trampoline; you can bounce, but if you bounce too hard with too much weight, you could potentially break the springs. In physics, this principle states that “no material can be compressed….or stretched beyond a maximum size.” Springs are not exempt from this physical rule. That is why when you’re bouncing on a trampoline, it is possible to receive a maximum height from a bounce that cannot be matched or improved.

Despite what you may think, there is science all around us. Physics is in everything we see and feel. This is no different for an object as simple as a trampoline. Your one simple bounce on a trampoline actually has multiple forces acting on it, and kinetic energies being transferred and returned. If you want to see for yourself the physics behind a trampoline, stop by your local Rebounderz in Apopka, Florida! We have an entire indoor trampoline park waiting for you to test out our trampolines and witness physics for yourself! Visit us today!