State Ampere's circuital law. Use this law to obtain the expression for the magnetic field inside an air cored toroid of average radius r having n-turns per unit length and carrying a steady current I.

State Ampere's circuital law. Obtain an expression for magnetic induction along the axis of toroid.

The magnetic field on the axis of a long solenoid having n turns per unit length and carrying a current is

State Ampere's circuital law. By using it derive an expression for magnetic field intensity at a point due to a straight current carrying conductor.

Derive an expression for the magnetic field due to a solenoid of length 2l , radius a, having n number of turns per unit length and carrying a steady current I, at a point on the axial line, distant r from the centre of the solenoid. How does this expression compare with the axial magnetic field due to a bar magnet of magnetic moment M?

The magnetic field B with in the solenoid having n turns per metre length and carrying a current of i ampere is given by

State the Biot-Savart law. Use it to obtain an expression for magnetic field at the centre of a current carrying circular loop.