Demos: 8A-03 Superconductivity
Show your class the Meissner Effect with this demonstration. By placing a superconductor disk in a bath of liquid nitrogen (to place it in a state of superconductivity) the disk will now exclude the magnetic field of a magnet from within itself when placed over the disk. The resulting force of repulsion is so greater than the weight of the magnet itself and it will float above the superconducting disk.
Directions for doing the demo: Set the Styrofoam container (which contains the experiment) on the surface of the document camera. Carefully pour liquid nitrogen into the opening containing the superconducting disk. With the tweezers pick up one of the small magnets and place it above the disk.
Suggestions for Presentation: Give the magnet a gentle push on one of its corners and it will freely rotate.
Applications: Superconductivity, Magnetism