Q. Two coils of self inductance 1 H and 3H are connected in series to support each other. Their mutual inductance is 6H. What is the self inductance of the combination ?

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Two coils of self inductance 1 H and 3H are connected in series to support each other. Their mutual inductance is 6H. What is the self inductance of the combination ?

Solution:

$L = L_1 + L_2 + 2 M$ = 1 + 3 +2 $times $ 6 = 16 H