Kinetic Energy and Recycling it

Kinetic Energy and Recycling it

by Tom

Do you know what kinetic energy is?  Well if you don’t, here’s a quick explanation of how kinetic energy works and how to recycle it.

Understanding Kinetic Energy

Kinetic energy is what I’m using right now to move my body while I’m typing.  It’s the energy that is needed to create motion.  The formula for kinetic energy is ½ mass of object being moved multiplied by the speed of the object squared in meters per second.  Or E = ½ M * V² . The answer is in Joules.

There is also potential energy. Potential energy is like kinetic energy but not in action yet.  For instance, a boulder that is balancing precariously on top of a hill has potential energy.  Here are two types of potential energy, one is gravitational potential energy, and the other is elastic potential energy. The formula for gravitational potential energy is the mass of the object in kilograms multiplied by the gravitational pull (in meters per second) multiplied by the height off the ground the object is in meters.  You might also represent the formula as this: PE = M*G*H.

Here’s an example of how to calculate kinetic energy!

Mass of Meteorite=5000 kilograms
Velocity of Meteorite=50,000 meters per second
5000 kilograms / 2 = 2500 kilograms
50,000 * 50,000 = 2,500,000,000
2,500,000,000* 2500 = 6,250,000,000,000 Joules of kinetic energy


Then there is a much more complicated formula for elastic potential energy.  To start, go and get a rubber band.  Now that you have it, hold it out, with both thumbs on either end and keep the rubber bands at their maximum length WITHOUT stretching them.  Right now, you are at the equilibrium of the rubber band.  Now, just for an example, move your right thumb one more centimeter away from your left.  Let’s just say that right now you are applying 1 Newton of force outwards stretching the rubber band.  Well, since for every action there is an equal and opposite reaction, there will be the -1 Newton’s of force pressing in on both of your thumbs.

Now to find the spring constant, divide that negative Newton by the distance from the equilibrium, which in this case is 1 centimeter (0.01 meters), which all together equals -100 Newton’s per meter.  In our case let’s switch – to + so that we can calculate the opposite reaction that will occur if we let one side of the rubber band go.  We can call this 100 Newton’s per meter k. Let’s call the amount you pulled the rubber band x.  k will be the constant, also known as the ratio of the rubber band.  So, in this case, for every centimeter you stretch the rubber band away from the equilibrium, there will be 2 Newton’s of force.  Since that is always true, this can be called a constant.  To get the amount of potential energy in Joules, divide k by 2 and square x.  Now multiply both and you have the total amount of potential energy.

What Can We Do to Recycle Kinetic Energy and What Are We Doing Already?

Piezoelectricity is a way that we can produce electricity-using vibrations in certain materials like quartz.  By vibrating or bending quartz we can separate the negative and positive charges so that when they come back together they will create electricity.  We can use this technique of creating electricity by making more clothes that have a kind of material in it that can generate electricity when bent by movements in the human body.  Also, we can put sensors in the roadway so that when the asphalt gets “bent”, we can capture the kinetic energy that the car used to run over the sensor and recycle it into more energy.  You might also find that artificial trees are being put up that have leaves that capture kinetic energy in that same way when the wind blows.

We can also install energy-capturing speed bumps that will shift down when cars go over them.  By that small shifting movement, the speed bump can generate electricity using pumps and wheels.  In addition to all this, here is another strategy that is just as good as all the other ones: simply use the shifting movements of regular driving to generate energy.  Yet another way to recycle kinetic energy is to put special energy-capturing tiles just around in the city so when people are walking around, they can step on the tiles and produce energy themselves!  But here’s a way to SAVE kinetic energy at home or on the road: drive only when you truly need to.  Otherwise, walk or bike or take any kind of public transportation.


I hope this gave you a good understanding of kinetic energy.  And in the future, if I were a scientist, I would try to create a super kinetic energy absorbent typing keyboard that would power the computer and I would teach more science to other enthusiastic scientists.


Posted December 13, 2011 by sciencesavestheworld