Question

Two long parallel wires are at a distance ` 2d` apart. They carry steady equal currents flowing out of the plane of the paper , as shown. The variation of the magnetic field `B` along the line `XX` is given by
A.
B.
C.
D.

Answer 1

Correct Answer - A
The magnetic field varies inversely with the distance for a long conductor . That is, ` B prop (1)/(d)`. According to the magnitude and direction shown graph (1) is the correct one.