Science & TechFact

In some metals, current flows forever without loss.

In 1911 Heike Kamerlingh Onnes cooled mercury to 4.2 kelvin and watched its electrical resistance drop abruptly to zero. In superconductors, a current once started keeps flowing practically indefinitely. The most powerful magnets in MRI scanners and CERN's particle accelerator use superconducting coils cooled with liquid helium. Room-temperature superconductivity has not been achieved.

Useful: Superconductors expel magnetic fields and therefore levitate above magnets; Japan's SCMaglev uses superconducting coils and runs at over 600 km/h.

Source: en.wikipedia.org

MaterialienMedizin Physik

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