Question

The direction of magnetic field at a point due to an infinitely long wire carrying current is:

• A. Parallel to the current
• B. Antiparallel to the current
• C. Along the perpendicular drawn from a point on the wire
• D. Perpendicular to the plane containing the conductor and the point

Answer 1

The correct option is D Perpendicular to the plane containing the conductor and the point

$\overrightarrow{B}\propto \overrightarrow{L}\times \overrightarrow{B}$

So using the right thumb rule , direction of B is perpendicular to plane containing wire and point.