79. Units of potential difference and electric field strength

The unit of the potential difference can be set using equation \((8-23)\) which defines the potential difference.

In SI units, work is measured in joules and charge in coulomb. A unit of potential difference is considered to be a potential difference where the movement of a \(1 \,q\) charge is accompanied by \(1\,joule\). This unit is called volt (V).

\( 1\,V \,= \,\frac{1\,{J}}{1\,{q}} \)

The unit of field strength in the SI is set on the basis of the unit of potential. If the potential difference between points at a distance of \(1 \,m\) in a uniform field is \(1 \,V\), the field strength will be equal to \(1 \,V/m\) (volts per meter).