Physics Of The Trampoline

I absolutely love jumping on the trampoline but I never really thought there was any physics involved. I knew you had to use a force to jump up and gravity pulls you back down obviously. An American inventor named George Nissen first invented the trampoline in 1935. (Silvia) A trampoline is defined as an elastic disc of hard canvas held up by metal springs attached to a metal skeletal frame. Kinetic and Potential energy allow you to be able to jump on a trampoline. PE=mgh this equation helps you find political energy due to gravity. (ferg)You calculate this by multiplying the mass of the person, by the height they are from the ground, by g, acceleration due to gravity. Acceleration is always 9.81m/s2. (ferg) That’s why it is harder for people
with more mass to jump as high as a smaller person because of the gravitational affect it has. There is also physics involved in the springs around the edge of the trampoline.
When a person jumps on the trampoline it causes the springs to compress together which causes the person to go high in the air while the spring goes back to the normal position. Larger masses make the spring stretch out more and can be shown in the equation F=ma. (ferg)Which is Newton’s 2nd law, F=force of gravity, m=mass, a=acceleration. (ferg) So the bigger the jump is the gravity force is also increased. Hooke’s law deals with the springs and equilibrium. So this law states that the spring will work to get back to equilibrium which means the springs will pull back against the weight of the person as they land. F=-kx is Hooke’s equation f=force, k=spring constant, x=displacement of spring. (ferg) Hooke’s law is like another form of potential energy. Did you know the springs and gravity on the trampoline keep you bouncing? Newton’s 3rd law states that for every action there is an equal opposite reaction. (Silvia) (Johnston) The equilibrium as described in Hooke’s law keeps you bouncing back into the air after you land on the trampolines surface again. (Hutchison) Kinetic energy is also a big part of the whole process
too. The formula for kinetic energy is KE=(1/2)mv^2, m=mass& v=velocity. (ferg)The higher the person is off the trampoline the higher the potential energy is. At the point above the trampoline where on is at rest, potential energy is at its highest.
But as the person starts to jump again all the energy’s decrease. The physics of jumping on a trampoline also includes Newton’s 3 laws. Newton’s first law states that an object will continue its path of motion unless acted on by outside force. (ferg) So when someone jumps on the trampoline the two outside forces present is gravity & the springs. (Hutchison) When jumping up gravity is the force that makes you come back down, so without gravity you would jump up and going all the way past the stars. So now that you know what gravity does in the process of jumping on the trampoline now we can talk about the other outside force, which are the springs. (ferg)So would the same amount of kinetic and potential energy be used if a whole bunch of people jumped on at the same time instead of just one? Of course the amounts would change because a group of people have a large mass unlike a single person would only have a small mass. A large group would definitely cause the springs to stretch and then compress at a slower rate because of the gravitational pull on every single person jumping up and then coming back
down. (Skhandelwal) The springs stretch and then compress back together to get to the normal stage, which is why you keep bouncing. (Hutchison) (Silvia) Because the springs are attached to the hard canvas it allows the canvas to move like an elastic band when you jump. So instead of just talking about the trampolines you jump on why not take a look at a physics way of trampolines. Physicists in France came up with a way to measure acceleration due to gravity by bouncing ultra cold atoms. This technique uses a firing laser pulse at a collection of free falling atoms, which makes some atoms bounce higher than others. When the atoms combine they create a interference pattern that reveals that g is 9.809 m/s2. (Johnston)This kind of trampoline is called the quantum trampoline. What happens in the process is the atom can absorb a photon from the pulse, and then make another photon but slightly a different energy. (Johnston)But if the pulse and momentum hit the atom just right it will make the atom bounce up and down like a gymnasts or acrobat on a trampoline. However sometime when the atom is given a pulse it can either gain twice the momentum or gain nothing at all. Now that they have proved that g can obtain a fraction of atoms It takes a lot of different patterns and observations when they recombine. All the atoms were cooled to an ultra cold temperature which allows atoms to set into the quantum state. (Johnston)The atoms were pulsed between 10-30 because the interference pattern was measured. Having the pulses in a pattern allowed them to determine the acceleration of gravity to by 9.809 m/s2 to three decimal places. (Johnston) This agreed with the geodetic system & it was a little bit more precise than Sackektts number. (Johnston) With this they believed their information would be a great help instead of just false information. Although this isn’t the first time these ultra cold atoms have been tested, all physicists are still finding new ways to find more accurate answers and different methods that work better. (Johnston) So what if the trampoline is old and worn out, Will it still function the same way as a new one? The answer is yes and no because the springs can get worn out and not come back together as fast as a usual one or it will break and spring off. (Skhandelwal)This happens if too much weight is added to a worn out trampoline. So now that you know about all the physics and equations need to function a trampoline. Try adding more people on the trampoline and try to see how much more you bounce back off of the trampoline. Also try to figure out how the gravitational force effects the way you bounce back off the trampoline. Now you know the different ways of how the trampoline works.