Superconductors :: essays research papers

  Ã‚  Ã‚  Ã‚  Ã‚  I am writing to inform you of a recent economic opportunity that could leave you rich if you choose to invest. The prospect of wealth relies on superconductors- the system of the future and present. You could earn millions by contributing to the research of superconductors.   Ã‚  Ã‚  Ã‚  Ã‚  Superconductors consist of an element, inter-metallic alloy, or compound that will conduct electricity without resistance (loss of energy flowing through the material) below a certain temperature. Once in motion, electrical current will flow forever in a closed loop of superconducting material, hence the high demand of such a product.   Ã‚  Ã‚  Ã‚  Ã‚  The development of superconductors has been a working progress for many years and some superconductors are already in use, but there is always room for improvement. In 1911, Dutch physicist Heike Kamerlingh Onnes first discovered superconductivity when he cooled mercury to 4 degrees K (-452.47 º F / -269.15 º C). At this temperature, mercury’s resistance to electricity seemed to disappear. Hence, it was necessary for Onnes to come within 4 degrees of the coldest temperature that is theoretically attainable to witness the phenomenon of superconductivity. Later, in 1933 Walter Meissner and Robert Ochsenfeld discovered that a superconducting material will repel a magnetic field. A magnet moving by a conductor induces currents in the conductor, which is the principle upon which the electric generator operates. However, in a superconductor the induced currents exactly mirror the field that would have otherwise penetrated the superconducting material - causin g the magnet to be repulsed- known today as the â€Å"Meissner effect.† The Meissner effect is so strong that a magnet can actually be levitated over a superconductive material, which increases the use of superconductors. After many other superconducting elements, compounds, and theories related to superconductivity were developed or discovered a great breakthrough was made. In 1986, Alex Muller and Georg Bednorz invented a ceramic substance which superconducted at the highest temperature then known: 30 K (-243.15 º C). This discovery was remarkable because ceramics are normally insulators – they do not conduct electricity well. Since their discovery the highest temperature for superconductivity to occur is 138 K (-130.15 º C).   Ã‚  Ã‚  Ã‚  Ã‚  The uses of superconductors are innumerable. They are used in the medical field often, so their use if valuable to common citizens such as yourself and me. Their uses medically include MRI (Magnetic Resonance Imaging) so that doctors do not have to invade the human body for exams, as well as speeding the results of the exams to almost instant information.