A long straight vertical copper wire is fixed on a laboratory bench and a steady…
PHYSICS · Multi-part · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current
Problem
A long straight vertical copper wire is fixed on a laboratory bench and a steady direct current is passed upward through it.
(i) Define magnetic field lines.
(ii) Explain why the magnetic field produced by the current in the wire has the shape of concentric circles centred on the wire.
(iii) Two points P and Q are located at the same horizontal level, P due east of the wire and Q due north of the wire. Draw a neat sketch of the magnetic field pattern around the wire and indicate the direction of the field at P and at Q.
(iv) State and explain the change, if any, in the directions indicated in part (iii) when the current in the wire is reversed.