Question

Derive an expression for the mutual inductance

between two long coaxial solenoids. What factors

affect it and how​

Answer 1

$\huge\frak\orange{answeR}$

Suppose a current i is passed through the inner solenoid . Let and be the no of turns it each solenoid of equal length l. Therefore, flux through each turn of solenoid is. The total flux through all the turns in a length l of is. And we know that where M is the mutual inductance.