What is Superconductivity?

Superconductivity is a property which enables electricity to flow through a conductor without any loss. Normally, there is some loss of electricity as heat when current flows through a conductor. This is because atoms of the conductor resist the flow of electrons. The resistance, however, depends on the temperature. Thus, cold conductors conduct electricity better than hot conductors. But some conductors when cooled below a certain temperature called critical temperature, let electricity flow through them without any loss. In other words, they become superconductors. The critical temperature at which a material starts superconducting is specific to that material.

The uses for materials capable of superconducting at room temperature are many. For instance, large currents can be carried to very far off places without any transmission loss by using very thin superconductors. Superconductors also make very powerful magnets. Thus, they can be used to propel superfast trains which move floating above the rails.