1827 – Germany
‘The electric current in a conductor is proportional to the potential difference’
In equation form, V = IR, where V is the potential difference, I is the current and R is a constant called resistance.
Ohm is now honoured by having the unit of electrical resistance named after him.
If we use units of V, I and R, Ohm’s law can be written in units as:
volts = ampere × ohm