Electromotive force (Cambridge International IGCSE Science)

Spec point — P4.2.4

Electromotive force

Extended Tier Only

• Electromotive force (e.m.f.) is the name given to the potential difference of the power source in a circuit
• It is defined as The electrical work done by a source in moving a unit charge around a complete circuit
• Electromotive force (e.m.f.) is measured in volts (V)

The e.m.f. is the voltage supplied by a power supply: 12 V in the above case