In the figure QR is a vertical conductor and the current I flows from R to Q. P is a point on the horizontal
plane and is to the south of the wire. The direction of the magnetic field at P due to the current will be towards:
According to right-hand thumb rule, if we hold the conductor QR in right hand with the thumb in the direction of Q, the direction of the magnetic field at a point will be along the fingers encircling the wire. Hence the direction of magnetic field will be towards east.