Question

A current through horizontal power lines flows in the west to east direction. What is the direction of the magnetic field at a point directly below it and at a point above it?

Answer 1

The direction of the magnetic field at a point directly below it :

1. The current is in the west-east direction.
2. Applying the right-hand thumb rule, we get that the direction of the magnetic field at a point below the wire is from south to north.

The direction of the magnetic field at a point directly above it :

1. The current is in the west-east direction.
2. The direction of the magnetic field at a point directly above the wire is from north to south.