A constant current flows in a horizontal wire in the plane of the paper from east to west as shown in Figure 13.5. The direction of the magnetic field at a point will be North to South
(a) directly above the wire
(b) directly below the wire
(c) at a point located in the plane of the paper, on the north side of the wire
(d) at a point located in the plane of the paper, on the south side of the wire
Hence, the correct answer is option (b).
Explanation:-
- We can use right-hand thumb rule to find out magnetic field due to a current-carrying wire. The magnetic field will form a close loop and if we see it from the East the loop will be clockwise.
- At a point above the wire, the direction of magnetic field will be towards North from south and at a point below the wire, the magnetic field will be towards south from North.
- At a point located towards north, the magnetic field will be into the paper. At a point located towards south the magnetic field will be out of the paper.