# Inductor inductance per turn?

Discussion in 'General Electronics Chat' started by wes, Jul 22, 2011.

1. ### wes Thread Starter Active Member

Aug 24, 2007
242
2
Hi, I was just thinking about inductors and it occurred to me that when measuring the inductance of a coil and hypothetically if the inductance
was 1 mH and the coil was 100 turns then if you measured the inductance of a single turn in that coil, it should be around 10 uH? Is this correct

If you took 100 10 uH turns of wire and made a coil out of them then it should be 1 mH right?

2. ### Adjuster Well-Known Member

Dec 26, 2010
2,147
300
Inductance is more closely related to the square of the number of turns N. When a closed magnetic circuit is used the inductance is pretty well directly proportional to N$^{2}$, in fact we use a formula L = N$^{2}$ * AL.

AL is the specific inductance of the magnetic core, often quoted in nano-Henries for 1 turn, or milli-Henries per 1000 turns.

Inductance is effectively a measure of flux linkages per unit current. If we double the number of turns, then the magnetising force for a given current is doubled, so the magnetic flux doubles (ignoring any non-linear effects). This flux also links with twice as many turns, so the number of flux-turns per Ampere has actually been multiplied by four.

Last edited: Jul 22, 2011