Question

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 the 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

The correct option is B

directly below the wire

Explanation:

1. To find the direction of the magnetic field, we use fleming's right-hand rule
   
2. It indicates the direction of the current induced as the conductor travels in a magnetic field.
3. The right hand is held vertically (at right angles) to each other with the thumb, index finger, and middle finger.
4. The thumb indicates the direction of movement of the conductor.
5. The index finger indicates the direction of the field (north to south). The index finger indicates the direction of the induced or generated current (the direction of the induced current is the direction of the conventional current, from positive to negative).
6. Therefore, when you put your right hand on the ground, the induced current flows from east to west along the second finger, the magnetic field flows from north to south, and the magnetic field acts directly below the wire.

Hence option $\left(b\right)$ is the correct option.