Understanding EMF and potential difference / voltage
The potential difference around a resistance is a measure of the amount of energy transferred by each coulomb of electricity as it passes though. The EMF of an electricity supply is a measure of the total energy given to each coulomb and the potential difference measured across a supply is the amount of energy in joules given to each colomb for the circuit connected to the supply.
These ideas are sometimes hard to understand and the notes aim to explain in more detail.
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