Question

A magnetic compass needle is placed in the plane of the paper.in which plane would you place a straight current carrying conductor near this needle so that there is no change in the deflection of the compass?state the condition of the current carrying conductor in which the compass needle will show the maximum deflection?

Answer 1

when current carrying conductor is kept perpendicular to the needle the needle does not deflect but when kept parallel above or below the needle it shows maximum deflection