Electric field strength

An electric field is a vector field that associates to each point in space the Coulomb force that would be experienced per unit of electric charge, by an infinitesimal test charge at that point. Electric fields are created by electric charges and can be induced by time-varying magnetic fields. The electric field combines with the magnetic field to form the electromagnetic field.

The electric field, ${\displaystyle \mathbf {E} }$, at a given point is defined as the (vector) force, ${\displaystyle \mathbf {F} }$, that would be exerted on a stationary test particle of unit charge by electromagnetic forces (i.e. the Lorentz force). A particle of charge ${\displaystyle q}$ would be subject to a force ${\displaystyle \mathbf {F} =q\mathbf {E} }$.

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