Assume that you have an electrical wire carrying current I d

Assume that you have an electrical wire carrying current I directed outward from the page. Which arrow represents the magnetic field direction at a point P (at the distance d from the wire)?

Solution

The upward arrow(towards +y axis) indictes magnetic field at point.

manetic filed lines are closed loops(cirlces) around the wire. The tangent drawn to the circle gives magnetic field direction.