Library / Tools / Physics equation calculator / Gravitational potential energy

Gravitational potential energy calculator

GCSEA-level Energy and power

The change in the energy stored by an object when it is lifted or lowered in a gravitational field.

E_p = m g Δh

This free calculator is for GCSE and A-level physics. Choose the quantity you want to find, enter the other values with their units, and it shows the working in the layout used in exams, with the answer to the number of significant figures you choose. The values shown are an example. Change them to your own.

Quantity to find

E_pChange in gravitational potential energy to find 235 J

mMass

gGravitational field strength constant

ΔhChange in height

Significant figures Value of g (N/kg)

Working

Write the equation
E_p = m g Δh
Constants used
g = 9.8 N/kg
Substitute the values
E_p = 4 × 9.8 × 6
Calculate
E_p = 235.2 J
Give the answer to 3 significant figures
E_p = 235 J

Worked example

Find Ep, the change in gravitational potential energy. Given: mass m = 4.00 kg; change in height Δh = 6.00 m; gravitational field strength g = 9.8 N/kg.

Write the equation
E_p = m g Δh
Constants used
g = 9.8 N/kg
Substitute the values
E_p = 4 × 9.8 × 6
Calculate
E_p = 235.2 J
Give the answer to 3 significant figures
E_p = 235 J

Symbols and units

Symbol	Quantity	SI unit
E_p	Change in gravitational potential energy	J
m	Mass	kg
g	Gravitational field strength (constant)	N/kg
Δh	Change in height	m

Gravitational potential energy: rearranged

To find change in gravitational potential energy: E_p = m g Δh
To find mass: m = E_p / (g Δh)
To find change in height: Δh = E_p / (m g)

Exam tip

Δh is the vertical change in height. It does not depend on the path taken.

Common questions

What is the formula for gravitational potential energy?

The equation is Ep = m g Δh, where Ep is the change in gravitational potential energy (J); m is the mass (kg); Δh is the change in height (m); g is the gravitational field strength (N/kg).

What units should I use for gravitational potential energy?

In SI units: change in gravitational potential energy in J, mass in kg, gravitational field strength in N/kg, change in height in m. The calculator also accepts common alternatives such as kilometres, grams or minutes, and converts them for you.

How do I rearrange Ep = m g Δh?

Rearranging gives these forms: to find change in gravitational potential energy: Ep = m g Δh. to find mass: m = Ep / (g Δh). to find change in height: Δh = Ep / (m g).

Practise gravitational potential energy questions

Include unit conversions (km, g, minutes…)

Press the button for a question with random numbers. Work it out on paper first, then type your answer.

Read the full explanation on the Gravitational potential energy formula page. More energy and power equations: Work done, Work done by an angled force, Elastic potential energy, Power from force and speed, Kinetic energy, Power, Energy transferred, Efficiency. See the full list on the physics equation calculator page.