What exactly is an ELECTRON VOLT as opposed to a VOLT?

Asked by: Joe Thomas

Answer

Electonvolt (symbol: eV) is a unit of ENERGY. One eV is equal to the amount of energy one electron acquires by accelerating (from rest) through a potential difference of one volt. It is usually used as a measure of particle energies although it is not an SI (System International) unit. The SI unit for energy is the JOULE. 1 eV = 1.602 x 10^-19 joule.

Volt is the SI unit of ELECTRIC POTENTIAL, potential difference or e.m.f. (electro motive force) defined as the difference of potential between two points on a conductor carrying a constant current of one ampere when the power dissipated between the points is one watt. It is named after Alessandro Volta (1745-1827)

It may help to realize that the electric potential is a property associated with the field in the space (i.e. in-between the capacitor plates conected to a battery), while the energy is associated with the particle you place into that field (and it depends on the particle).
Answered by: Anton Skorucak, M.S. Physics, PhysLink.com Creator