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Help ro create an inductance L :

Principle of measurment:

All coil gather one inductance L and one resistance R. The group makes up the impedance Z which is complex. |Z| can be calculate with the Pythagor's theorem.

                      |Z|²=r²+L²w²   

( Also Z=r + Lw*i )

In this expression ,which is applicable with a sinusoidal generator of frequency F (in Hz) w is the beat in rad.s-1

w=2*pi*F  (pi=3.14159265359)

If R is very lower than L and if Lw is great, Z is almost equal to Lw.( We will see after what you can do if R isn't negligible.

If you connect a generator with a sinusoidal current F which deliver an alternative current I of known frequency F the difference of potential at the self's bounds is:

V=ZI

In this way we've got V=LwI

Then L=V/(w*I)

So we must build a sinusoidal generator of current I and of frequency F.

If the resistance isn't negligible you must remove, now, the real component of all the impedance Zm.

We've got Lw²=Z²m - r²

Alsoi L² = (Z²m -r²) /w²   avec w=2*pi*f

(Of course to measure r you use an ohmmeter)

Calculation to determine a frequency generated by a LC circuit:

For an electric oscillator we've got:

            (with w the beat)