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.In order to perform this demonstration, you''ll need a small amount of liquid nitrogen. That''s why this
demonstration is best left to your science teacher. You''ll also need a superconductor like the one used in this demonstration - yttrium-based (YBa2Cu3O7. When pouring liquid nitrogen please be careful to prevent any splashing. Always conduct the experiments in a well-ventilated room, and do not touch any items immersed in the liquid nitrogen with your hand until they have warmed to room temperature.
More abstracts about the Superconductors - Floating Magnet