Some subjects in school, like physics, can be a challenge. We hear that it is hard and we accept that this will be the case for us. It is amazing how easy physics can be if we can relate it to something that we do or something that we have. You might not think of this at the beginning, but it is possible to learn a lot of physics as you enjoy your trampoline. Let’s take a look!

I believe that it would be appropriate to start with a discussion on energy. Lets say that when you have jumped on the trampoline as hard as you can and you are as close to the ground as possible that this height is zero. As you are going up, from the zero position, you are losing velocity in kinetic energy (KE) and gaining potential energy (PE). Energy is conserved. Total energy is equal to the kinetic energy plus the potential energy. See equation 1. It will be helpful to have some other formulas as well. See equations 2 and 3.

Equation 1) Total E = KE + PE

Equation 2) KE =1/2mv2 (m is mass, v is velocity)

Equation 3) PE=mgh (m is mass, g is acceleration, h is height)

I will use myself as an example so that we can do some calculations. We will need to know some specific information.

My weight: 100 kg
The maximum velocity that I have leaving the mat: Vi = 7.0 meters/second (It helps to have a friend with a radar gun.)

Total E = KE=1/2(100kg)(7m/sec)2 = 2450J @ zero height.

(J is the abbreviation for Joule – 1J = 1kg*m2/s2)

Now lets take another snap shot at 2 meters. I have gained some PE and lost some KE, but my total energy is still the same. (See Equation 1) Now using Equation 3 let me calculate the PE at 2 meters:

PE = mgh = 100kg * 9.8m/sec2 * 2m = 1960J @ 2 meter height

Now I want to know what my KE is at the 2m point. Based on the conservation of energy, I know that if I subtract my 2 meter height PE from my 0 meter height KE, I will get my answer for KE at 2 meters. See below:

2450J (zero height KE) – 1960 J (2m height PE) = 490 J of KE at 2m

Now I want to know how fast I am going at 2 meters. I will use equation for this.

490J = 1/2mv2 = ½(100kg)v2

v2 = 9.8

v = 3.13m/s

In addition to energy and velocity, there are many other things that we can learn about on our trampoline. In addition to helping you keep fit and begin to establish a healthy lifestyle, your trampoline can help you better understand physics!
You should be able to use to help convince your parents that you need a trampoline in your backyard!

Good luck and happy jumping!