Perform an investigation to demonstrate magnetic levitation
- When a superconducting material in its normal state is placed in a magnetic field, the magnetic field strength inside the material is almost the same as the magnetic field strength outside the material.
- When such a material is in its superconducting state, currents flow within it to produce a magnetic field that cancels the applied magnetic field within the material.
- Meissner Effect: The expulsion of the magnetic field from inside a superconductor.
- The Meissner effect can be observed by placing a rare earth magnet over a superconductor suspended in liquid nitrogen:
- The magnet should hover above the superconductor.
- This is because the currents in the semiconductor that expel the magnet’s field create magnetic poles that cause repulsion between the superconductor and the magnet.