Magnetic levitation
Magnetic levitation, maglev, or magnetic suspension is a method by which an object is suspended with no support other than magnetic fields. Magnetic force is used to counteract the effects of the gravitational acceleration and any other accelerations.
The two primary issues involved in magnetic levitation are lifting forces: providing an upward force sufficient to counteract gravity, and stability: ensuring that the system does not spontaneously slide or flip into a configuration where the lift is neutralized.
The sizes of magnets also has a role in the levitation. While using smaller magnets it is easier to control levitation and experimental conditions.
Magnetic levitation is used for maglev trains, contactless melting, magnetic bearings and for product display purposes.
Magnetic Levitation Media
An experiment with off-the-shelf components uses a magnet glued to the end of a rotary multitool. Its rotation causes a second magnet to levitate millimeters away from the first one.
A superconductor levitating a permanent magnet
An example of magnetic pseudo-levitation with a mechanical guide (wooden rod) providing stability
The Transrapid system uses servomechanisms to pull the train up from underneath the track and maintains a constant gap while travelling at high speed
Floating globe. Magnetic levitation with a feedback loop
Aluminium foil floating above the induction cooktop due to eddy currents induced in it
Permanent magnet stably levitated between fingertips
Diamagnetic levitation of pyrolytic carbon
A live frog levitates inside a 32 mm diameter vertical bore of a Bitter solenoid in a magnetic field of about 16 teslas
A Levitron branded top demonstrates spin-stabilized magnetic levitation
