Posted by Øystein Rustad (148.122.36.76) on October 18, 2003 at 07:54:18:
Hello, just wanted to mention about the tippe top.
Very similar to the last drawing in MT
The top flips upside down, and has been a "mystery" to science for a long time. The center of the total mass rises, but does not really reflect in lost rotational energy.
Some scientists done heavy work on this thing, and they came to that the only way the rotational energy could be lost as the mass rises, is to surface friction......
http://www.havingasoftware.nl/software/ThreeDimSim/ex8/tippetop.htm
http://www.physics.brown.edu/Studies/Demo/solids/demos/1q6030.html
The tippe top is a top consisting of slightly more than a hemisphere resting on a cylindrical stem (concentric with the rotation axes) which served as a handle. The surprising thing about this top is that upon spinning on the hemispherical portion, it spontaneously turns itself upside-down and begins spinning on the stem.
I would like to conduct some experiments on this, but that would need some handcrafting skills :-)
I would like to spin up a mass and measure the tourque as it is flipped from horisontal to vertical...
Any ideas ?
Øystein