In 1842, Samuel Earnshaw formulated what is now known as Earnshaw’s Theorem, which states that magnetic levitation cannot be achieved solely using stationary magnets. To maintain stable levitation, an external force must be introduced.

This device demonstrates stable magnetic levitation of a small magnet by leveraging an external force generated by diamagnetic surroundings, specifically pyrolytic graphite. Diamagnetic materials interact with external magnetic fields by repelling them, creating a stabilizing force that counteracts instability. In this setup, the small magnet is lifted by a larger magnet positioned above it. However, without the presence of the pyrolytic graphite, the small magnet would either rest on the bottom plate or be attracted to the larger magnet, preventing stable levitation.

The device highlights how even the subtle diamagnetic force can be harnessed for educational purposes and fun experiments. The small magnet can be rotated effortlessly by blowing air on it, and it will spin for a surprisingly long time before coming to a stop. Achieving stable levitation requires precise positioning of the small magnet in the narrow gap between the two graphite sheets. This is done by carefully adjusting a screw until equilibrium with gravity is reached.

Materials

• 1x large lifting magnet (NdFeB, 12 × 12 × 12 mm)
• 1x small magnet (NdFeB, smaller than the graphite)
• 2x graphite sheets (20 × 20 × 1 mm, available online)
• 2x M3 screws