Question

The coefficients of self induction of two coils are respectively 2 mH and 3 mH. They are coupled so as to oppose each other. What will be their self inductance if their mutual inductance is 1 mH?

• A. 7 mH
• B. 5 mH
• C. 3 mH
• D. 1 mH

Answer 1

Answer: (C)

3 mH

Answer 2

$L = L_1 + L_2 -2 M = 2 + 3 - 2 \times 1 = 3$ m H