Voltage

Types of voltage

There are two types of energy transfers in

When energy is ‘lost’ by a coulomb (i.e. ‘given’ to a component), it’s called ‘potential difference’.
When energy is ‘gained’ by a coulomb (usually from a cell), it’s called ‘EMF’.

Potential difference is the work done by unit charge.
It’s a type of voltage that represents the energy transferred to or from a component in a circuit (not from the cell/battery).
If the potential difference across a component is, for example, , that menas that of charge transfers of energy to the component.
It’s called the ‘potential difference’ because it is the difference in energy (work done) or volts across a component.
Potential difference can be measured with a voltmeter.