
Two circular coils and with their centres lying on the same axis have the same number of turns and carry equal currents in the same sense. They are separated by a distance, have different diameters but subtend the same angle at a point lying on their common axis. The coil lies exactly midway between coil and the point . The magnetic field at point due to coils and is and respectively.


Important Questions on Sources of Magnetic Field
Figure shows a long wire bent at the middle to form a right angle.


The below figure shows two closed paths wrapped around two conducting loops carrying currents and What is the value of the integral for
(a) path and (b) path ?

Each of the eight conductors in the below figure carries of current into or out of the page. Two paths are indicated for the line integral What is the value of the integral for path and path ?

Three distinct current carrying wires intersect a finite rectangular plane . The current in the left wire and the loop is . The direction of current in left-most wire and right-most loop is downwards as shown in the figure. The current through the middle wire is adjusted so that the path integral of the total magnetic field along the perimeter of the rectangle is zero, that is, Then the current is

Rank the value of for the closed paths shown in figure from the smallest to the largest.

Eight wires cut the page perpendicularly at the points shown in figure. A wire labelled with the integer carries the current , where . For those wires with odd , the current is out of the page; for those with even , it is into the page. The value of along the closed path indicated and in the direction shown.

