QUOTE (Doug @ 2 Jul 2007, 09:49)
<{POST_SNAPBACK}>I wonder if this could ever be put to a practical use? How much energy is required to cool the magnet? That is where it fails to be practicable.
It is the superconductor that requires cooling and repels all magnetic fields allowing levitation. Currently it is unknown if room temperature superconduction is possible and although there are frequently new and strange materials being annouced that push the temperature a little closer towards room temp. there is still a huge way to go! (about 150 degrees) and since the most advanced ceramic superconductor of today is made of thallium, mercury, copper, barium, calcium, strontium and oxygen (T_superconduct=138 K) then there are so many variables such as molecular configurations etc. to investigate that nobody knows just what is possible...
It is conventional to cool the superconductor with liquid nitrogen and the price of this effectively determines the feasibility of the technology. If we were to get fusion power to work and so have almost limitless energy then producing large amounts of the stuff would be easy given that the atmosphere is 75% nitrogen! Then room temperature superconduction is not essential...
Obviously fusion is almost as big an *if* as room-temp-super is!
Goedel
