Question

Two conducting circular loops of radii R₁ and R₂ are placed in the same plane with their centres coinciding. If R₁ >> R₂ , the mutual inductance M between them will be directly proportional to
1. R₁/R₂
2. R₂/R₁
3. (R₁)²/R₂
4. (R₂)²/R₁

Answer 1

Correct Answer - Option 4 : (R₂)²/R₁

Mutual inductance between two coils in the same plane with their centres coinciding is given by

\(M = \frac{{{\mu _0}}}{{4\pi }}\left( {\frac{{2{\pi ^2}R_i^2{N_1}{N_2}}}{{{R_o}}}} \right)\;\)