Home > categories > Minerals & Metallurgy > Magnetic Materials > Why do superconductors repel magnetic fields?
Question:

Why do superconductors repel magnetic fields?

Superconductors work as, when cooled to a certain point, they lose all electrical resistance. This near absolute zero temperature causes atoms to cease random vibrations, thereby allowing un-impeded flow for its electrons and a total loss of electrical resistance. The Meissner effect is a common property of these zero electrical resistant superconductors. It works because the magnet’s magnetic field cannot penetrate the superconductor, causing its lines of force to be expelled back at it. This has the effect of creating a mirror-image of the magnet within the superconductor and, through the expelled lines of force it is creating, causes itself to levitate.QUESTION : Why does the superconductor repel magnetic fields?

Answer:

The exclusion of magnetic flux is brought about by electrical screening currents that flow at the surface of the superconducting material and which generate a magnetic field that exactly cancels the externally applied field inside the superconductor. Superdiamagnetism established that the superconductivity of a material was a stage of phase transition. Superconducting magnetic levitation is due to superdiamagnetism, which repels a permanent magnet, and flux pinning, which prevents the magnet floating away.

Share to: