Levitation

Levitation is the effect of an object floating in the gravitation field without any obvious support of the surrounding objects. The laws of physics allow various types of levitation, and the easiest way to make a thing levitate is to use magnetic forces. It turns out that it is impossible to create a static configuration of magnets with one of them levitating; even if an equilibrium is created, it is always unstable. However, if we employ some additional physics principle, e.g. the gyroscopic effect of a spinning top, we can stabilize the equilibrium. This is the case of Super Levitron that can be seen in the first two rows of photographs. It is a spinning magnetic top hovering above a base that creates a strong magnetic field of a specific shape. The levitating globe, on the contrary, uses an electric current through a coil and a feedback to stabilize the equilibrium. Superconductors provide still another possibility of levitation thanks to the Meissner effect. The superconductor tries to expel the magnetic field from its volume, which results in a repulsive force, or can lead to fixing the mutual position of the magnet and the superconductor (4th and 5th rows). This enables to make a bearing completely without friction (the last row).