Two coupled inductors L₁ = 8H and L₂ = 32H have coefficient of coupling K = 0.4. The mutual inductance between them is

Correct option is C

$$\bullet L_1 = 8\,H \\[4pt]\bullet L_2 = 32\,H \\[4pt]\bullet \text{Coefficient of coupling } K = 0.4$$

The formula for mutual inductance M between two coupled inductors is given by:

​$$M=K\sqrt{L_1L_2}\\M=0.4\times\sqrt{8\times32}\\M=0.4\times\sqrt{256}=0.4\times16=6.4\ \text{H}$$​​

So, the mutual inductance between the inductors is 6.4 H.

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