Derive an expression for mutual inductance of two coaxial solenoids

CBSE Class 12
1

Derive an expression for mutual inductance of two coaxial solenoids of same length but different radius and number of turns

2

Let the subscript 1 denote the iner coil and the subscript 2 denote the outer coil
Since the two coils are coaxial thus they will have complete flux linkage i.e. the flux produced at the center due to 2 nd coil will entirely pass through the 1st coil.
Thus,
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