Gravitational Potential Energy: formula
Enter the mass in kilograms, the gravitational acceleration and the height in meters. Gravitational potential energy is mass times gravity times height, with 9.81 meters per second squared on Earth, 1.62 on the Moon and 3.71 on Mars. The height is measured above a chosen reference level, such as the ground or the bottom of a fall.
The result is in joules, with kilowatt-hours shown for scale.
Gravitational Potential Energy: worked example
| Mass (kg) | 10 |
|---|---|
| Gravity (m/s²) | 9.8 |
| Height (m) | 5 |
| Potential energy (J) | 490.5 |
| Potential energy (kWh) | 0.00014 |
Only differences in height matter, so the reference level is arbitrary. Near the surface gravity is nearly constant, but over large heights it decreases. Real systems lose energy to friction and air.
Elastic and chemical energy are separate forms.
Gravitational Potential Energy: changing Mass (kg)
| Mass (kg) | Potential energy (J) | Potential energy (kWh) |
|---|---|---|
| 8 | 392.4 | 0.00011 |
| 9 | 441.5 | 0.00012 |
| 10 (example) | 490.5 | 0.00014 |
| 11 | 539.6 | 0.00015 |
| 12 | 588.6 | 0.00016 |
Gravitational Potential Energy: compare input ranges
| Input | Tested from | To | Potential energy (J): low input | Potential energy (J): high input | Swing |
|---|---|---|---|---|---|
| Mass (kg) | 9 | 11 | 441.5 | 539.6 | 98.1 (20%) |
| Height (m) | 4.5 | 5.5 | 441.5 | 539.6 | 98.1 (20%) |
| Gravity (m/s²) | 9 | 11 | 450 | 550 | 100 (20%) |
Gravitational Potential Energy: individual input comparisons
| Input | Value | Potential energy (J) | Potential energy (kWh) |
|---|---|---|---|
| Mass (kg) | 8 | 392.4 | 0.00011 |
| 9 | 441.5 | 0.00012 | |
| 10 | 490.5 | 0.00014 | |
| 11 | 539.6 | 0.00015 | |
| 12 | 588.6 | 0.00016 | |
| Gravity (m/s²) | 8 | 400 | 0.00011 |
| 9 | 450 | 0.00013 | |
| 10 | 500 | 0.00014 | |
| 11 | 550 | 0.00015 | |
| 12 | 600 | 0.00017 | |
| Height (m) | 4 | 392.4 | 0.00011 |
| 4.5 | 441.5 | 0.00012 | |
| 5 | 490.5 | 0.00014 | |
| 5.5 | 539.6 | 0.00015 | |
| 6 | 588.6 | 0.00016 |
Gravitational Potential Energy: combined input changes
| Mass (kg) / Gravity (m/s²) | 8 | 10 | 12 |
|---|---|---|---|
| 8 | 320 | 400 | 480 |
| 9 | 360 | 450 | 540 |
| 10 | 400 | 500 | 600 |
| 11 | 440 | 550 | 660 |
| 12 | 480 | 600 | 720 |
Gravitational Potential Energy: which assumptions move the result?
Gravitational Potential Energy: values and definitions
| Quantity and definition | Value used |
|---|---|
| Mass (kg) | 10 |
| Gravity (m/s²) — 9.81 on Earth. About 1.62 on the Moon. | 9.8 |
| Height (m) | 5 |
| Potential energy (J) | 490.5 |
| Potential energy (kWh) | 0.00014 |
Gravitational Potential Energy: half and double Mass (kg)
| Mass (kg) | Potential energy (J) |
|---|---|
| 5 | 245.3 |
| 10 | 490.5 |
| 20 | 981 |
Common error: Using the mass in pounds. The formula wants kilograms, and pounds without conversion overstate the energy by more than double.
Physics & Mechanics calculators: Work and Power Calculator, Wavelength and Frequency Calculator, Projectile Motion Calculator, Free Fall Calculator, Centripetal Force Calculator, Pendulum Period Calculator.
Lifting a mass stores energy equal to its weight times the height. Ten kilograms raised 5 meters under standard gravity holds 490.5 joules, which is what it would release if it fell. In kilowatt-hours that is a tiny 0.00014, which is why gravity storage needs enormous masses or heights to matter.
Measure the height as the vertical drop, not the path taken. A ramp changes the effort but not the stored energy.
See impact speed on the free fall calculator, the energy in motion on the kinetic energy calculator and the work on the work and power calculator. The force and Hooke's law pages cover related mechanics, and the pendulum period calculator shows energy exchange in a swing.
Does the reference height matter?
Only differences in height matter, so you can choose any level as zero, as long as you are consistent.
How does potential energy become kinetic energy?
As an object falls its height and potential energy drop while its speed and kinetic energy rise by the same amount, ignoring air resistance.
What is the formula for gravitational potential energy?
Mass times gravitational acceleration times height, so a 10 kilogram mass lifted 5 meters on Earth gains 490.5 joules.