How to Calculate the Gravitational Potential Energy of an Object

Last Updated: September 2, 2020

Gravitational Potential Energy (GPE) is the energy of place or position. It depends on 3 things: the force of gravity (9.81), the mass of the object (in kilograms), and the height the object is off the ground (in meters).^{[1]
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Research source} GPE can be changed to Kinetic Energy. The unit for GPE is joules (j).

Steps

1
Gather your data. First you need to get the data needed for this calculation. You should get the mass on kilograms (Kg), the height the object is off the floor in meters (m) and the gravity pull which is 9.81 (m/s2).^{[2]
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- Example: A 2 Kg book being held 2 meters off the ground with a gravity pull of 9.81 m/s2.
2
Write down the formula. So to get the GPE of an object you need a formula, the formula is MASS X GRAVITY X HEIGHT (M X G X H).^{[3]
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3
Put the data in the formula. So next you need to replace the letters (M, G, and H) with your data.^{[4]
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Research source} So for the book example, it would be: 2 x 9.81 x 2.
4
Solve the formula. The last step is to solve the formula and there you go, you have the GPE of your object.^{[5]
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Research source} The GPE of the book is 39.24 Joules.

Community Q&A

Question

How do I calculate the height using this formula?

Community Answer

You can multiply the mass by the gravity, all divided by the GPE. That will give you the height.
Question

I got 9.81. What was my mistake?

Community Answer

If you followed the instructions above and performed the same calculations only to get 9.81, then you simply entered a number into your calculator incorrectly, so some math went wrong along the way. The number 9.81 in this situation represents the average gravity of earth.
Question

What is energy measured in?

Community Answer

Energy is measured in joules (J). If it reaches a thousand joules, you can convert it into kiloJoules (kJ).