Question

Two coils are Placed close to each other. The mutual inductance of the pair of coils depends upon

• A. Relative position and orientation of the two coils
• B. the materials of the wires of the coils
• C. the current in the two coils
• D. the rates at which currents are changing in the two coils

Answer 1

Answer: (A)

Relative position and orientation of the two coils

The coupled flux of two coils system is used to define the mutual inductance between the coils. The mutual inductance between the coils is $M_{21}=\frac{N_2{\varphi }_{21}}{I_1}$

So it is defined as the proportionality between the emf generated in coil 2 due to the current flows in coil 1. Thus It depends on the relative position and orientation of two coils.