Show Me Some Science: Diamagnetic Levitation
A thin piece of graphite levitates above a bunch of magnets!
What’s Happening?
It’s not surprising to see a paperclip or another small object stick to a magnet. This phenomenon is called ferromagnetism, and on an atomic level the atoms in the paperclip act like little magnets and all align to the field from the magnet. An object which is ferromagnetic will stick to any magnet.
Diamagnetism is the opposite effect. A diamagnet has atoms that act as small magnets, but they will all align opposite of the field from another magnet. Therefore Diamagnets repel every magnet!
Diamagnetism is much weaker than ferromagnetism, so it can be difficult to see. However, we use a piece of pyrolytic graphite, which is diamagnetic and also very light weight. A series of strong (neodymium) magnets is setup in a checkerboard fashion with alternating North and South Poles facing upwards to create a strong magnetic field. The result is the the graphite levitates in the air above the magnets!