Derive an expression for the magnetic field along the axis of an air-cored solenoid, using
Channel: Doubtnut
Date: 2020-08-02

Derive an expression for the magnetic field along the axis of an air-cored solenoid, using Ampere's circuital law. Sketch the magnetic field lines for a finite solenoid. Explain why the field at the exterior mid point is weak while at the interior it is uniform and strong.