Question

Question 9
A constant current flows in a horizontal wire in the plane of the paper from east to west as shown in figure. The direction of 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

Answer 1

Option (a) is correct.
This can be found out by using right-hand thumb rule. The direction of magnetic field at a point will be north to south will be directly above the wire.