An electric potential (also called the electric field potential, potential drop or the electrostatic potential) is the amount of
work needed to move a unit
positive charge from a reference point to a specific point inside the field without producing any acceleration. Typically, the reference point is Earth or a point at Infinity, although any point beyond the influence of the electric field charge can be used.
According to classical
electrostatics, electric potential is a
scalar quantity denoted by V, equal to the
electric potential energy of any charged particle at any location (measured in
joules) divided by the
charge of that particle (measured in
coulombs). By dividing out the charge on the particle a quotient is obtained that is a property of the electric field itself.
This value can be calculated in either a static (time-invariant) or a dynamic (varying with time)
electric field at a specific time in units of joules per coulomb (J C−1), or
volts (V). The electric potential at infinity is assumed to be zero.
A generalized electric
scalar potential is also used in
electrodynamics when time-varying electromagnetic fields are present, but this can not be so simply calculated. The electric potential and the
magnetic vector potential together form a
four vector, so that the two kinds of potential are mixed under