The phenomena, science, and applications of moving electric charges, as contrasted with → electrostatics. More specifically, the branch of physics concerned with the → interaction of → electric currents with → magnetic fields and → electric fields or with other electric currents.
âhanrobâ-ye barqi (#)
A temporary magnet made by coiling wire around an → iron core. When current flows in the coil, or → solenoid, the iron becomes a → magnet. The electromagnet acts as a magnet only so long as the current is flowing in the solenoid.
Of or pertaining to electromagnetism or electromagnetic fields.
Fr.: champ électromagnétique
A region of space consisting of coupled electric and magnetic lines of force at each point, generated by time-varying currents and accelerated charges.
Fr.: force électromagnétique
The fundamental force that is associated with electric and magnetic fields. One of the four fundamental forces of nature, it is carried by photons.
Fr.: induction électromagnétique
The production of an → electromotive force in a circuit caused by a variation in the magnetic flux through the circuit. If this variation is produced by a change in the current flowing in the circuit itself, it is called → self-induction. If due to the variation in a current in some other circuit, it is called mutual induction. See also → Faraday's law of induction.
Fr.: potentiel électromagnétique
Fr.: rayonnement électromagnétique
Radiation propagating in the form of an advancing wave in electric and magnetic fields. It includes radio waves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
Fr.: spectre électromagnétique
The range of frequencies over which electromagnetic waves are propagated. → electromagnetic radiation.
Fr.: théorie électromagnétique
electromagnetic theory of light
negare-ye barqâmeqnâti-ye nur
Fr.: théorie électromagnétique de la lumière
The theory describing light as a wave phenomenon resulting from the combination of two electric and magnetic fields vibrating transversely and mutually at right angles. → electromagnetic radiation; → electromagnetic wave; → Maxwell's equations.
Fr.: onde électromagnétique
A wave produced by oscillation or acceleration of an electric charge. → electromagnetic radiation.
1) The science dealing with the physical relations between → electricity
and → magnetism. Same as
→ electromagnetic theory.
electromotive force (EMF)
niru-ye barqrân (#)
Fr.: force électromotrice
The force, analogous to a pressure, which maintains a flow of electricity through a closed circuit. It is the algebraic sum of the → potential differences acting in the circuit. The unit of electromotive force is the → volt.
The → elementary particle that possesses the smallest possible negative → electric charge. This structureless particle has an intrinsic → spin (1/2), a mass of 9.109 382 91 (40) x 10-31 kg, and an electric charge of 1.602 176 565(35) × 10-19 → coulombs, or 4.803 204 51(10) × 10-10 → esu.
Fr.: capture d'électron
A process whereby an → unstable atom becomes stable. In this process, an → electron in an atom's inner shell is drawn into the → nucleus where it combines with a → proton, forming a → neutron and a → neutrino. The neutrino escapes from the atom's nucleus. The result is an element change, because the atom loses a proton. For example, an atom of → carbon (with 6 protons) becomes an atom of → boron (with 5 protons). Electron capture is also called K-capture since the captured electron usually comes from the atom's K-shell. See also → neutronization.
bâr-e elektron (#)
Fr.: charge de l'électron
Fr.: configuration électronique
Of an atom, a form of notation which shows how the electrons are distributed among the various atomic orbital and energy levels. The format consists of a series of numbers, letters and superscripts. For example, 1s2 2s2 2p3 means: 2 electrons in the 1s subshell, 2 electrons in the 2s subshell, and 3 electrons in the 2p subshell.
vâgeni-ye elektron (#)
Fr.: dégénérescence des électrons
A → degenerate matter in which electrons are very tightly packed together, as in a white dwarf, but cannot get closer than a certain limit to each other, because according to quantum mechanics laws (→ Pauli exclusion principle) the lowest energy levels can be occupied by only one electron. Therefore, electrons are forced into high energy states. And the significant pressure created by these high energy electrons supports white dwarf stars against their own gravity.
cagâli-ye elektroni (#)
Fr.: densité électronique