Inductance
"L"
What it is
The property of an electric circuit by which an electromotive force is
induced in it by a variation of current either in the circuit itself or in a
neighboring circuit. Inductance is a measure of the amount of magnetism that can
be stored in a body by an electrical current.. Large coils of wire can store
more magnetism and thus have more inductance. Magnetism is not only stored in
the wire but in the air and in materials about the wire. Inserting iron cores
into coils of wire greatly increases the amount of magnetism that can be stored
and therefore increases the inductance. Inductance is also defined as the
property of a circuit that opposes a change in current. Inductance has the
dimensions of permeability * length.
Reluctance is the reciprocal of inductance multiplied by a constant.
History
Joseph Henry (1797-1898) discovered inductance (self induction) in 1842 when he
noticed that a spark was produced when an electrical circuit was broken. Henry
also determined that circuits containing inductance tended to oscillate. The
discovery of inductance opened an exciting new dimension of exploration.
Common equations
inductance = area * permeability / length
frequency^2 = 1 / (inductance * capacitance)
inductance = reluctance * k = k / permeance
Units
henrys
millihenrys
abhenrys
stathenrys
intl henrys
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