Assume we’re holding a current-carrying straight conductor in our right hand, with the thumb pointing in the current’s direction. The right-hand thumb rule states that our finger should wrap around the conductor in the direction of the magnetic field lines. Consider a current flowing in an east-west direction across a horizontal power line. The magnetic field at a position above the wire is directed north to south using the right-hand thumb-rule. At a position directly above the wire, the magnetic field is directed from south to north.The compass needle deflects in the north-south direction when a magnetic compass is placed below in the current-carrying cable.
What will happen to a compass needle when the compass is placed below a wire and a current is made to flow through the wire? Give a reason to justify your answer.
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Principal, Babu Daudayal SVM, Mathura