Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

farad
the basic unit of measure in capacitors. A capacitor charged to 1 volt with a charge of 1 coulomb (1 ampere flowing for 1 second) has a capacitance of 1 farad.
Faraday effect
the rotation of the plane of polarization of a high-frequency signal (microwave RF, optical field) in the presence of a magnetic field.
Faraday rotation
(1) rotation in the direction of polarization experienced by a wave traveling through an anisotropic medium. Important examples of media in which the phenomenon occurs include the earth's ionosphere and ferrites biased by a static magnetic field.

(2) depolarization caused in a plasma (e.g., the ionosphere) resulting from interaction between the ions of the plasma and the magnetic field of the wave.

(3) rotation in the polarization vector experienced by a wave after it propagates through a gyromagnetic medium.
Faraday rotator a magneto-optical device that changes the orientation plane of polarized light when it passes parallel to a
magnetic field through a substance with pronounced absorption lines.
Faraday shield
an electrostatic (E field) shield made up of a conductive or partially conductive material or grid. A Faraday cage or screen room is effective for protecting inside equipment from outside radiated RF energies.
Faraday's law
one of Maxwell's equations that describes the fundamental relationship between induced voltage and a time-varying magnetic field. For a conducting coil, the induced voltage is proportional to the time rate of change in the magnetic flux linking the coil. This change may be produced either by actual variation of field strength or by relative motion between coil and field. See also Maxwell's equations.