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

Options

A.
B.
C.
D.

Answer

A

Explanation

To the right of 2nd wire, field due to both wires is upwards. To the left of 1st wire, field due to both is downwards. In between the wires, field is in opposite direction.