Question

when placed above a current carrying straight wire, a compass needle points to the north but when placed below the same wire then Needle points to the south. in which direction is the current flowing in the wire? a) east b) west c) north d) south

Answer 1

Dear Student,

A compass needle points towards magnetic south pole(which is the geometric north pole of earth).
When placed above a current carrying straight wire, a compass needle points to the north(which is the magnetic south pole), Hence magnetic field at point just above the wire is towards geometric south, so using Right hand thumb rule we find that current is towards east direction.

Regards