The field normal to the plane of a wire of `n` turns and radis `r` which carriers `i` is measured on the axis of the coil at a small distance `h` from the centre of the coil. This is smaller than the field at the centre by the fraction.

The field normal to the plane of a wire of 15 turns and radius r which carries 1 A is measured on the axis of the coil at a small distance d from the centre of the coil. This is smaller than the field at the centre by the fraction

The field normal to the plane of a wire of 15 turns and radius r which carries 1 A is measured on the axis of the coil at a small distance d from the centre of the coil. This is smaller than the field at the centre by the fraction

The magnetic field normal to the plane of a coil of N turns and radius r which carries a current I is measured on the axis of the coil at a distance h from the centre of the coil. This is smaller than the field at the centre by ther fraction.

The field due to a wire of n turns and radius r which carries a current I is measure on the axis of the coil at a small distance h form the centre of the coil. This is smaller than the field at the centre by the fraction:

The field due to a wire of n turns and radius r which carries a current I is measure on the axis of the coil at a small distance h form the centre of the coil. This is smaller than the field at the centre by the fraction:

Magnetic field B on the axis of a circular coil and far away distance x from the centre of the coil are related as :