Coil Inductance Formula

An inductor is otherwise called as coil or reactor. The inductance of the coil can be found by coil inductance formula which is based on computing the known values such as the number of turns, relative permeability, loop diameter, wire diameter and permeability of free space. An inductance of coil formula itself is computed based on the basic loop inductance. The inductor of the coil is found by its inductance and the standard SI unit of inductance is henry (H).

Inductance of Coil Formula


Inductance = n2 × μo × μr × ( l / 2 ) × ( ln( ( 8 × l ) / d) -2)


N = Number of Turns
μr = Relative Permeability
L = Loop Diameter(m)
D = Wire Diameter(m)
μo = Permeability of Free Space(4 × π × 10-7)

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Inductors play a pivotal role in the operation of camera flash lamp circuitry. Inductors are one among the linear circuit elements that make up the electronic circuits, so coil inductance formula is very much essential to calculate such inductors inductance value.

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