Two coils of self inductances $L_1$ and $L_2$ are kept close to each other so that the effective flux in one is completely linked with the other. What is the mutual inductance M between them?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $(L_1 L_2)^{1/2}$
When the flux in one coil is completely linked with the other, the mutual inductance (M) between the coils,
$M=\sqrt{L_1L_2}$