Your Equation

Library / Tools / Physics equation calculator / Energy transferred (E = QV)

Energy transferred (E = QV) calculator

GCSEA-level Electricity

The energy transferred when a charge moves through a potential difference.

E = Q V

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

108 J

Working

  1. Write the equation
    E = Q V
  2. Substitute the values
    E = 12 × 9
  3. Calculate
    E = 108 J
  4. Give the answer to 3 significant figures
    E = 108 J

Worked example

Find E, the energy transferred. Given: charge Q = 12.0 C; potential difference V = 9.00 V.

  1. Write the equation
    E = Q V
  2. Substitute the values
    E = 12 × 9
  3. Calculate
    E = 108 J
  4. Give the answer to 3 significant figures
    E = 108 J

Symbols and units

SymbolQuantitySI unit
EEnergy transferredJ
QChargeC
VPotential differenceV

Energy transferred (E = QV): rearranged

  • To find energy transferred: E = Q V
  • To find charge: Q = E / V
  • To find potential difference: V = E / Q

Exam tip

One volt is one joule per coulomb.

Common questions

What is the formula for energy transferred?

The equation is E = Q V, where E is the energy transferred (J); Q is the charge (C); V is the potential difference (V).

What units should I use for energy transferred?

In SI units: energy transferred in J, charge in C, potential difference in V. The calculator also accepts common alternatives such as kilometres, grams or minutes, and converts them for you.

How do I rearrange E = Q V?

Rearranging gives these forms: to find energy transferred: E = Q V. to find charge: Q = E / V. to find potential difference: V = E / Q.

Practise energy transferred (e = qv) questions

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

Related

Read the full explanation on the Electrical work done formula page. More electricity equations: Charge, current and time, Ohm’s law, Electrical power, Electrical power, Resistors in series, Resistors in parallel, Resistivity, EMF and internal resistance. See the full list on the physics equation calculator page.