A constant current flow 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
A constant current flow 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

Solution: The answer is (b) directly below the wire

We can determine the direction of the magnetic field beneath the wire by applying the right-hand thumb rule.