Industrial superconductivity

This article presents ways in which superconductivity opens up new possibilities for industrial processes and industrial measurements. There are two characteristics that define a superconductor: first is the sudden disappearance of resistivity at very low temperatures. Second is the Meissner effect. A metal expels any magnetic field inside it when it cools through Tc and becomes superconducting. By expelling the field and thus distorting nearby magnetic field lines, as shown, a superconductor will create a strong enough force field to overcome gravity. This gives rise to the memorable photos of a small crystal floating freely above a cooled magnet