DocuWatch on Facebook
Art America Britain History Science Societies War Shop
DocuWatch

Superconductivity

« String Theory and M-Theory

The Big Bang Machine »

Description

Superconductivity

An introductory video, filmed in 1965, by Alfred Leitner on Type-I superconductors. Leitner used a liquid Helium cryogenic apparatus (similar to the equipment seen in his video on superfluids) to cool Tin below its transition temperature. Below the transition temperature, the metal became a superconductor, exhibiting zero electrical resistance. The famous Meissner effect was also demonstrated, where the superconductor expels all magnetic fields, causing a permanent magnet to levitate above it.

From Wikipedia

Superconductivity is an electrical resistance of exactly zero which occurs in certain materials below a characteristic temperature. It was discovered by Heike Kamerlingh Onnes on April 8, 1911 in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. It is also characterized by a phenomenon called the Meissner effect, the ejection of any sufficiently weak magnetic field from the interior of the superconductor as it transitions into the superconducting state. The occurrence of the Meissner effect indicates that superconductivity cannot be understood simply as the idealization of perfect conductivity in classical physics.

The electrical resistivity of a metallic conductor decreases gradually as the temperature is lowered. However, in ordinary conductors such as copper and silver, this decrease is limited by impurities and other defects. Even near absolute zero, a real sample of copper shows some resistance. Despite these imperfections, in a superconductor the resistance drops abruptly to zero when the material is cooled below its critical temperature. An electric current flowing in a loop of superconducting wire can persist indefinitely with no power source.

In 1986, it was discovered that some cuprate-perovskite ceramic materials have critical temperatures above 90 K (−183 °C). These so called high-temperature superconductors renewed interest in the topic because of the prospects for improvement and potential room-temperature superconductivity. From a practical perspective, even 90 K is relatively easy to reach with readily available liquid nitrogen (which has a boiling point of 77 K), resulting in more experiments and applications.

Other videos in channel "Atoms":

 Atoms Old and New Atoms Old and New An Expensive Theology - (1992) An Expensive Theology - (1992) Atom Atom
Atoms and their Electrons Atoms and their Electrons Chemistry Chemistry
Chemistry - A Volatile History Chemistry - A Volatile History Chemistry 1A Chemistry 1A Cold Fusion ? - (2005) Cold Fusion ? - (2005)
Copenhagen Fall Out - Niels Bohr & Werner Heisenberg Copenhagen Fall Out - Niels Bohr & Werner Heisenberg Do You Know what time It Is? - (2008) Do You Know what time It Is? - (2008)
E=mc2 - Einstein and the World's Most Famous Equation E=mc2 - Einstein and the World's Most Famous Equation Einstein Einstein Einstein, Albert Einstein, Albert
Einstein's Biggest Blunder Einstein's Biggest Blunder Einstein's Brain Einstein's Brain Einstein's Equation of Life & Death - (2005) Einstein's Equation of Life & Death - (2005)
Einstein's Miracle Year - (1996) Einstein's Miracle Year - (1996) Einstein's Unfinished Symphony - (2005) Einstein's Unfinished Symphony - (2005) Elementary Particles and the Laws of Physics - Richard Feynman Elementary Particles and the Laws of Physics - Richard Feynman
Faster Than the Speed of Light Faster Than the Speed of Light Feynman On Quantum Mechanics Feynman On Quantum Mechanics Fundamentals of Physics with Ramamurti Shankar Fundamentals of Physics with Ramamurti Shankar
Great Ideas of Classical Physics 02 - 08 Great Ideas of Classical Physics 02 - 08 Greatest Discoveries - Chemistry Greatest Discoveries - Chemistry Greatest Discoveries - Physics Greatest Discoveries - Physics
Hitler's Bomb - (1992) Hitler's Bomb - (1992) How Long Is A piece Of String ? How Long Is A piece Of String ? Introduction to Chemical Engineering Introduction to Chemical Engineering
Molecules With Sunglasses Molecules With Sunglasses Most Of Our Universe Is Missing Most Of Our Universe Is Missing Nanoutopia Nanoutopia
Nikola Tesla - Master of Lightning Nikola Tesla - Master of Lightning Our Friend The Atom Our Friend The Atom Particle Physics 01 Particle Physics 01
Particle Physics 02 Particle Physics 02 Project Poltergeist Project Poltergeist Quantum Mechanics Explained Quantum Mechanics Explained
Six Billion Dollar Experiment  Six Billion Dollar Experiment Strangeness Minus Three Strangeness Minus Three String Theory String Theory
String Theory and M-Theory String Theory and M-Theory Superconductivity Superconductivity The Big Bang Machine The Big Bang Machine
The Birth Of Liquid Crystals The Birth Of Liquid Crystals The Good German The Good German The Hunt for Higgs The Hunt for Higgs
The Man Who Loved Trees The Man Who Loved Trees The Mysterious Mr. Tesla The Mysterious Mr. Tesla The Path To Nuclear Fission The Path To Nuclear Fission
The Riddle of AntiMatter The Riddle of AntiMatter The Secret Life of Waves The Secret Life of Waves Time Lords Time Lords
Time Trip Time Trip Uncertain Principles Uncertain Principles Uranium Goes Critical - (1979) Uranium Goes Critical - (1979)
Visions Of The Future 03 - The Quantum Revolution Visions Of The Future 03 - The Quantum Revolution What Gives Particles Mass? What Gives Particles Mass? What is One Degree? What is One Degree?
What On Earth Is Wrong With Gravity? What On Earth Is Wrong With Gravity? Zero G Zero G  
Video channels
Videos in this channel
Adsense
Featured
Featured
Featured
Featured
Featured
Featured