Question

Two coils having self-inductances of 60 mH each are coupled with each other. If the coefficient of coupling is 0.75, calculate the mutual inductance between them.

Answer 1

Given data:

Self-inductance of each coil: L₁ = L₂ = 60 mH

Coefficient of coupling: k = 0.75

Formula for Mutual Inductance:

The mutual inductance (M) between two coils is given by:

M = `k sqrt(L_1L_2)`

Substituting the Values:

M = `0.75 xx sqrt ((60 xx 10^-3) xx (60 xx 10^-3))`

M = `0.75 xx sqrt(3600 xx 10^-6)`

M = 0.75 × (60 × 10⁻³)

M = 0.75 × 0.06

M = 0.045 H

M = 45 mH

The mutual inductance between the two coils is 45 mH.