1. Place a retort stand on the plank as shown in the figure.
2. Pass a copper wire through hole of the plank and rubber knob of the retort stand in such a way that the wire be arranged in a vertical position and not touch the stand.
3. Connect the two ends of the wire to a battery via switch. Allow the current flows through wire.
4. By sprinkling the iron fillings around the wire, we can observe the magnetic field lines are in circular shape.
Conclusion :
Hence it is proved that “Magnetic field lines are closed loops”.
