OnlineCBT
Physics · PYQ NEET UG 2021
हिन्दीTwo conducting circular loops of radii \( R_1 \) and \( R_2 \) are placed in the same plane with their centres coinciding. If \( R_1 \gg R_2 \), the mutual inductance M between them will be directly proportional to:
Correct answer · Option 2
\( \frac{R_2^2}{R_1} \)
Explanation
Magnetic field at the center due to outer loop \( B_1 = \frac{\mu_0 I_1}{2R_1} \). Flux linked with inner loop \( \Phi_2 = B_1 A_2 = (\frac{\mu_0 I_1}{2R_1})(\pi R_2^2) \). Mutual inductance \( M = \frac{\Phi_2}{I_1} \propto \frac{R_2^2}{R_1} \).
