Question

Define superconductors,semi-conductors,non-conductors and give their importance?

Answer 1

Superconductors are materials that achieve a state of zero resistance at a certain temperature called a transition temperature. The Transition temperature is much below room temperature (Highest achieved i believe is something around -100 Celsius). Superconductivity has some interesting consequences to the lack of resistance. For one, a current, once applied will continue to flow indefinitely. A superconductor will also repel any change in the magnetic field. Theres some pretty cool demonstrations with magnets floating. The magnetic repulsion (diamagnetism) comes from the induction of a "supercurrent" within the superconductor. Because of the slight amount of energy required to create this superconductor the transition temperature is a function of magnetic field strength. The point at which a superconductor will no longer form due to the surrounding magnetic field is called the critical field strength. The search for a room temperature superconductor is an active persuit in the field of physics and actually finding one that is ductile would change the way we transmit electricity forever, as well as the many many applications it could have in digital electronics.

Semiconductors are generally conductive at room temperature and decrease in resistivity as a function of temperature, up until a critical temperature where they exponentially increase to essentially infinite resistance becoming an insulator. Semi conductors are used prolifically in electronics.

Insulators or Non-conductors will not permit the flow of electrons through them. They are used in electrical safety normally as the coating of the wires. They also compose the soles of many shoes to prevent serious electric shock when working with live electricity.