First, liquid oxygen is made by passing gaseous oxygen through a tube submerged in liquid nitrogen. Then the oxygen is poured between the poles of a strong electro magnet. The paramagnetic nature of the oxygen causes an induced dipole. As a result, the oxygen is suspended in the magnetic field. Once the field is disabled the oxygen returns to its original state and falls from the magnet. Note: liquid oxygen is dangerous and can cause spontaneous combustion please do not try this at home.
Other demonstrations from MIT
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