Abstract:
Based on laws in electromagnetism and superconductivity and relevant experimental results, it is explained that the half levitation of the so-called room-temperature ambient-pressure superconductor LK-99 above the upper pole face of a permanent magnet disk originates from the torque and force on the ferromagnetic impurities located in a nonuniform applied magnetic field. The locked levitation or suspension of a coated Y-Ba-Cu-O conductor sample above or below the disk is due to the position recovering Lorentz force on the supercurrent induced by sample movement in the non-uniform field, not to the Meissner effect and so-called quantum locking.