1M40.90 - Celts or Rattle Backs
Put the Celt on a smooth surface. Start it spinning in a clockwise direction. After a few turns it will stop and then go in its preferential counter-clockwise direction. It will also turn in a counter-clockwise direction if you just start it rocking by tapping one end.
The large Celt can be set to rotate in either direction or not at all.
- Rod Cross, "Rocking and Rolling Rattlebacks", TPT, Vol. 51, #9, Dec. 2013, p. 544.
- Steve Dail, "Rattleback Bet", TPT, Vol. 49, #5, May 2011, p. 316.
- Ronald D. Edge and Richard Childers, "Curious Celts and Riotous Rattlebacks", TPT, Vol. 37, #2, Feb. 1999, p. 80.
- H. Richard Crane, "The Rattleback Revisited", TPT, Vol. 29, #5, May 1991, p. 278.
- Jearl Walker, "The Amateur Scientist: The Mysterious 'Rattleback': A Stone That Spins in One Direction and Then Reverses", Scientific American, Vol. 241, #4, Oct. 1979, p. 172.
- Jodi and Roy McCullough, "Center of Gravity with a Celt", The Role of Toys in Teaching Physics, p. 4.114.
- Jearl Walker, "1.109. Rattlebacks", The Flying Circus of Physics Ed. 2, p. 54.
- Jearl Walker, "2.72. The Rebellious Celts", The Flying Circus of Physics with Answers.
- Christopher P. Jargodzki and Franklin Potter, "226. The Mysterious", Mad About Physics, p. 90, 226.
- Robert Ehrlich, "F.5. Rattleback", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 71 - 72.
- Sir Hermann Bondi, "The Rigid Body Dynamics of Unidirectional Spin", Proceedings of the Royal Society of London, Vol. 405, #1829, June 1986, p. 265 - 274.
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