inductance

/in duk"teuhns/, n. Elect.1. that property of a circuit by which a change in current induces, by electromagnetic induction, an electromotive force. Symbol: L Cf. inductive coupling, mutual inductance, selfinductance.2. inductor (def. 1).[188590; INDUCT + ANCE]
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Property of a conductor, sometimes in the shape of a coil, that is measured by the size of the electromotive force (emf), or voltage, induced in it, compared with the rate of change of the electric current that produces the voltage.A steadily changing electric current produces a varying magnetic field, which induces an emf in a conductor that is present in the field. The magnitude of this voltage is proportional to the rate of change of the current. The inductance is the proportionality factor. The unit of inductance is the henry, named after Joseph Henry; one henry is equivalent to one volt divided by one ampere per second.* * *
property of a conductor (often in the shape of a coil) that is measured by the size of the electromotive force, or voltage, induced in it, compared with the rate of change of the electric current that produces the voltage. A steady current produces a stationary magnetic field; a steadily changing current, alternating current, or fluctuating direct current produces a varying magnetic field, which, in turn, induces an electromotive force in a conductor that is present in the field. The size of the induced electromotive force is proportional to the rate of change of the electric current. The proportionality factor is called the inductance and is defined as the value of the electromotive force induced in a conductor divided by the magnitude of the rate of change of the current causing the induction.If the electromotive force is induced in a conductor that is different from the one in which the current is changing, the phenomenon is called mutual induction, exemplified in a transformer. A changing magnetic field caused by a varying current in a conductor, however, also induces an electromotive force in the very conductor that carries the changing current. Such a phenomenon is called selfinduction, and the quotient of the induced electromotive force and the rate of change of the current is specified as selfinductance.A selfinduced electromotive force opposes the change that brings it about. Consequently, when a current begins to flow through a coil of wire, it undergoes an opposition to its flow in addition to the resistance of the metal wire. On the other hand, when an electric circuit carrying a steady current and containing a coil is suddenly opened, the collapsing, and hence diminishing, magnetic field causes an induced electromotive force that tends to maintain the current and the magnetic field and may cause a spark between the contacts of the switch. The selfinductance of a coil, or simply its inductance, may thus be thought of as electromagnetic inertia, a property that opposes changes both in currents and in magnetic fields.Inductance depends on the size and shape of a given conductor, the number of turns if it is a coil, and the kind of material near the conductor. A coil wound on a soft iron core far more effectively chokes the increase of a current than the same coil with an air core. The iron core increases the inductance; for the same rate of change of the current in the coil, a greater opposing electromotive force (back emf) is present to choke the current.The unit of magnetic inductance is the henry, named in honour of the 19thcentury American physicist Joseph Henry (Henry, Joseph), who first recognized the phenomenon of selfinduction. One henry is equivalent to one volt divided by one ampere per second. If a current changing at the rate of one ampere per second induces an electromotive force of one volt, the circuit has an inductance of one henry, a relatively large inductance.* * *
Universalium. 2010.
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inductance — [ ɛ̃dyktɑ̃s ] n. f. • 1893; du rad. de induction, d apr. l angl. inductance ♦ Phys. Coefficient d auto induction (⇒ henry). Par ext. Le circuit caractérisé par son coefficient d auto induction. ⇒ self inductance. Inductance d arrêt, destinée à… … Encyclopédie Universelle
Inductance — In*duc tance, n. (Elec.) Capacity for induction; the coefficient of self induction. Note: The unit of inductance is the henry. [Webster 1913 Suppl.] … The Collaborative International Dictionary of English
Inductance — [engl.], Induktivität … UniversalLexikon
inductance — (n.) 1886, from INDUCT (Cf. induct) + ANCE (Cf. ance) … Etymology dictionary
inductance — ► NOUN Physics ▪ the property of an electric conductor or circuit that causes an electromotive force to be generated by a change in the current flowing … English terms dictionary
inductance — [in duk′təns] n. [ INDUCT + ANCE] 1. the property of an electric circuit by which a varying current in it produces a varying magnetic field that induces voltages in the same circuit or in a nearby circuit: it is measured in henrys: symbol, L 2.… … English World dictionary
Inductance — Electromagnetism Electricity · … Wikipedia
Inductance — Bobine simple L inductance d’un circuit électrique est un coefficient qui traduit le fait qu’un courant le parcourant crée un champ magnétique à travers la section entourée par ce circuit. Il en résulte un flux du champ magnétique à travers la… … Wikipédia en Français
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inductance — The coefficient of electromagnetic induction; the unit of i. is the henry. [see induction] * * * in·duc·tance in dək tən(t)s n 1 a) a property of an electric circuit by which an electromotive force is induced in it by a variation of current… … Medical dictionary