# What Is the Formula in Calculating EMF?

By Staff WriterLast Updated Mar 25, 2020 2:47:58 PM ET

Electromotive force, or EMF, is calculated using the formula e = E / Q, where e is the EMF, E is the energy in Joules and Q is the charge. The EMF measures the potential difference between the terminals of a cell when the circuit is switched off.
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