(i) The magnitude of magnetic field produced by a current carrying circular coil at a point is directly proportional to the current flowing through the circular coil . Thus as the amount of current flowing through the circular coil increases, the magnetic field produced at a point in a circular coil increases.
(ii) Magnetude of magnetic field produced at a point in a current carrying circular coil is inversely proportional to the distance of point from the coil. Thus the magnetic field produced at a point decreases as the distance increases from the coil.
(iii) The magnetic field produced by a current carrying wire at a given point depends directly on the current passing through it. Therefore, if there is a circular coil having n turns, the field produced in n times as that produced by a single turn. This is because the current in each circular turn has the same direction, and the field due to such turns then just adds up .
