Chronology | Current Month | Current Thread | Current Date |
[Year List] [Month List (current year)] | [Date Index] [Thread Index] | [Thread Prev] [Thread Next] | [Date Prev] [Date Next] |
In a previous note, I pointed out that our "tube" is made of four or five
nested copper pipes about 2.5 m long. Our magnets are "cattle" magnets about
3" long purchased from a local farm supply store. They are small cylindrical
steel magnets of much lower cost and strength than neodymium. Our machinist
also fashioned a similar cylindrical piece of nonmagnetized soft iron. We
drop this through the tube for comparison with the magnet's fall time. It
also dispels the notion that friction slows the magnet's fall.
Roger
Commercial versions of the demo use the supermagnets in an *aluminum*
tube. Such tubes, in six foot lengths and various diameters, are readily
available in hardware stores.
-- Donald