MadSci Network: Physics |
I was just curious, if a magnet is spun over copper does the magnet's magnetic field penetrates the copper or just move across its outer surface??? Please let me know asap. Thanks Shawn!!
Hi Shawn!
Most substances are magnetically permeable.
If you know that a magnet spinning over metal causes electrons in the metal to move, then it stands to reason that the magnetic field must be penetrating the metal. How else could the magnet have an effect?
There is one curious element, the metal bismuth, that actually excludes the field -- the lines of force are actually deflected around it! This effect is called diamagnetism, and causes bismuth to be repelled by a magnet.
Here's a link to a cool experiment you can do that demonstrates diamagnetic levitation.
Try the links in the MadSci Library for more information on Physics.