SUPERCONDUCTIVITY is a phenomenon of exactly zero electrical resistance and expulsion of magnetic flux fields occurring in certain materials, called SUPERCONDUCTORS, when cooled below a characteristic critical temperature. It was discovered by Dutch physicist Heike Kamerlingh Onnes on April 8, 1911, in Leiden. Like ferromagnetism and ... إقراء المزيد

CLASSICAL ELECTROMAGNETISM or CLASSICAL ELECTRODYNAMICS is a branch of theoretical physics that studies the interactions between electric charges and currents using an extension of the classical Newtonian model. The theory provides an excellent description of electromagnetic phenomena whenever the relevant length scales and field strengths are ... إقراء المزيد