Post: Kinetic Energy

We talked about energy and gravitational potential energy. Now, we will briefly go over another form of energy, the energy of motion, called kinetic energy. It is an amazing form of energy that shows your movement. When you are working out, you’re using kinetic energy. I will explain how this form of energy is related to potential energy.

What Is Kinetic Energy?

Kinetic energy is the energy of motion. An example of using kinetic energy is when a car is driving, or when you are running around. Like in the other post, gravitational potential energy is the energy in an object based on the position in a gravitational field and how high or heavy it is. So, if a car is on a hill and it stops at a red light and drives down the hill when it turns green, the car’s potential energy turns into kinetic energy.

How the Formula Works

The formula for kinetic energy is $KE = \frac{1}{2}mv^2$, where $m$ is the mass and $v$ is the velocity. From this formula, you might be able to assume that it has something to do with motion just by looking at it (the velocity shows you how it is related to moving or acting). Let’s say a 5 kilogram object is moving 4 meters a second. It’s kinetic energy would then be 40 joules.

Real Life Example

Let’s say you are playing soccer and you kick a ball, and it goes high. To calculate the energy of the ball at its highest point, you will need to multiply its weight times its height. That’s its gravitational potential energy (it is not required to multiply gravity as a separate term because weight includes the gravitational force). When the ball falls down, it releases kinetic energy. To find the kinetic energy of the ball, you can follow the formula above: $KE = \frac{1}{2}mv^2$.

At the ball’s highest point, the potential energy is high because the ball is higher. The kinetic energy is low because the ball doesn’t move.

Conclusion

I showed you two forms of energy, and how they work. It is interesting how both forms of energy relate to each other. Potential energy is the energy an object has based on its height, while kinetic energy is the energy of an object when it is moving. Make sure to check my other posts on physics. Thank you for reading!