Question

There is a straight wire carrying current as shown in the figure. What is the direction of the magnetic field around the wire when the reference point is above the wire?

• A. Clockwise direction along the circle encircling the wire.
• B. Anti-clockwise direction along the circle encircling the wire.
• C. In the direction of the current.
• D. Opposite to the direction of the current.

Answer 1

The correct option is B

Anti-clockwise direction along the circle encircling the wire.

The direction of the magnetic field can be determined by right-hand thumb rule - "When the thumb points in direction of the current, the direction of curling of fingers will give the direction of magnetic field."

So, in the current situation, the direction of the magnetic field is in anti-clockwise direction as observed from the reference point that lies above.