Q8.A wire is perpendicular to the plane of the paper. A ring of compass needles surrounds the wire in the plane of the paper with center of ring being the center of the wire .Initially there is no current in the wire. What happens after a steady dc current is established in the wire?
Answer : Option AExplaination / Solution: The current carrying wire has a magnetic field around it and the lines of force are in the form of concentric circles with their centers on the wire.