An **electromagnetic field** (also **EMF** or **EM field**) is a physical field produced by moving electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces of nature (the others are gravitation, the weak interaction, and the strong interaction).

The field can be viewed as the combination of an electric field and a magnetic field. The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The way in which charges and currents interact with the electromagnetic field is described by Maxwell's equations and the Lorentz force law.

From a classical perspective, the electromagnetic field can be regarded as a smooth, continuous field, propagated in a wavelike manner; whereas from the perspective of quantum field theory, the field is seen as quantized, being composed of individual particles.

Read more about Electromagnetic Field: Structure of The Electromagnetic Field, Dynamics of The Electromagnetic Field, Electromagnetic Field As A Feedback Loop, Mathematical Description, Relation To and Comparison With Other Physical Fields, Health and Safety

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**Electromagnetic Field**- Health and Safety

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... to get a current, which typically causes the wire coil to build up a large

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**Electromagnetic Field**

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**electromagnetic**potential by To see that this equation is invariant, we transform the coordinates (as ... Using the antisymmetry of the

**electromagnetic field**one can either reduce to an identity (0 = 0) or render redundant all the equations except for those with λ,μ,ν = either 1,2,3 or 2,3,0 or 3,0,1 or 0,1,2 ... The covariant derivative of the

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... Maxwell had studied and commented on the

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**electromagnetic**phenomena by employing a new version of Maxwell's equations ... of electrodynamics in curved spacetime are (in cgs units) where Fab is the

**electromagnetic field**tensor representing the

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—Clara Barton (1821–1912)