A current through a horizontal power line flows in east to west direction. What is the direction of magnetic field at a point directly below it and at a point directly above it?
To find Magnetic Field, we will use the Right Hand Thumb Rule.
- Since current flows from East to West, pointing out thumb towards West
- If we curl our fingers, that will show direction of magnetic field
So, for a point directly above wire, magnetic field is into the paper
and for a point directly below wire, magnetic field is out of the paper