A tightly wound solenoid of length l and cross sectional area `A_(1)` is partly inserted co-axially
Channel: Doubtnut
Date: 2020-02-20

A tightly wound solenoid of length l and cross sectional area `A_(1)` is partly inserted co-axially into another tightly wound solenoid of length l and cross section `A_(2) (gt A_(1))`. The centres of the two solenoids are separated by `x (lt l)`. Assume that `A_(2) lt lt x^(2), A_(2) lt lt l^(2)`. Calculate the total magnetic field energy inside the solenoid when both of them carry same current (I) in the same sense. Number of turns in each solenoid is N.