Electromagnetic field

The electromagnetic field (EMF) is composed of two related vectorial fields, the electric field and the magnetic field. This means that the vectors (E and B) that characterize the field each have a value defined at each point of space and time. If only E, the electric field, is nonzero and is constant in time, the field is said to be an electrostatic field.

The electromagnetic field generates a force F on a charged particle, given by the Lorentz equation

where is the charge of the particle, and v is its current velocity (expressed as a vector.)

The behaviour of electromagnetic fields can be described with Maxwell's equations, and their quantum basis by quantum electrodynamics.