Imagine a classroom of students fixated on a tiny magnet the size of the head of a pencil. The magnet is resting on a mysterious black disc, but the magnet does not stick to the disc. Both the black disc and the magnet sit on top of an upside-down Styrofoam cup. Here comes the fun part… when the teacher pours liquid nitrogen on the black disc, the tiny magnet lifts off the disc and spins in the air. The students cheer… and the teacher is ready to explore the science of superconductors with her students.
- A small amount of liquid nitrogen
- A superconductor, like the one used in this demonstration - yttrium-based (YBa2Cu3O7)
- Small magnet
- Heavy protective gloves
- Safety glasses