Post: Gravitational Potential Energy
In the last blog post we talked about what energy is, and now we will go into a form of energy called gravitational potential energy. We will also go through some real life examples on where you can use this form of energy. Hopefully, after this you will know what gravitational potential energy is and how to use it in real life. Now let’s get into what this energy really is.
What Is Gravitational Potential Energy?
Gravitational potential energy is the stored energy in an object based on the positition in a gravitational field and how high or heavy it is. For example, a pencil on a table has more potential energy than one on the ground. Or a flying plane has more potential energy than a race car on the road. An example of gravitaional potential energy turning into kinetic energy would be when a kid sitting down goes down a slide. The kid is up at the top - that’s the potential energy. When the kid slides down, the potential energy turns into kinetic energy.
How the Formula Works
Gravitational potential energy can be calculated by weight times height - but that only works when you are near Earth’s surface. If you are a rocket in space, or a spacecraft launching into space, the gravitational force will change, including your gravitaional energy. The real formula is $GPE = mgh$, where $m$ is the mass, $g$ is the acceleration due to gravity, and $h$ is the height.
Finding the Weight
So, let’s say there is a wood log carrying 2 pounds on the left and $W$ pounds on the right. Suppose that the weight on the left goes 2 inches lower, and the weight on the right goes 1 inch higher. There is also a 1 pound weight in the middle that goes up 2 inches. We want to find out how much weight the log would have to carry on the right to balance the wood log, disregarding the weight of the log. We can figure this out using gravitational potential energy: the sum of the weights times the heights. This would give us the equation: (-2)(2) + (1)(2) + ($W$)(1) = 0, which would give us the solution $W$ = 2 pounds.
As in the equation, the gravitational potential energy is 0 when the object is still and doesn’t move
Conclusion
Now you know how to find the gravitational potential energy and how it is used in real life. This concludes my blog post about gravitational peotential energy. I hope you enjoyed reading this. Make sure to check out my other physics posts on this website!