Inductance calculator

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This calculator uses Weinstein's formula (1884) for the self-inductance of a multi-layer, n-turn circular coil (mean radius a) of rectangular cross-section (mean radius a, axial breadth b, radial depth c). This complex formula is valid for air-coils, with any combination of a, b, c and n. n is the total number of turns (not per layer). See [Rosa].
The dimensions a, b and c are expressed in centimeters, the inductance in millihenrys. Note: use decimal point not comma.

a = cm
b = cm
c = cm
n = turns

L = millihenry

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In the following version, the number of turns n can be calculated from given values of the dimensions a, b, c and the inductance L.

a = cm
b = cm
c = cm
L = millihenry

n = turns

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Javascript program by E.H. Dooijes, June 2008.