A long solenoid with closely wound turns has n turns per unit of its length. A steady current
Channel: Doubtnut
Date: 2020-08-02

A long solenoid with closely wound turns has n turns per unit of its length. A steady current I flows through this solenoid. Use Ampere's circuital law to obtain an expression, for the magnetic field, at a point on its axis and close to its mid point.