3B10.25 - Inertia of Motion - Standing Pulse - Chain

Code Number:
Demo Title:
Inertia of Motion - Standing Pulse - Chain
Area of Study:
Oscillations & Acoustics
Bead Strings, Glass Beaker, and Dynabrolly Apparatuses.

See also 1F30.15 in Mechanics.

Try to pull the end of the chain rapidly out of the beaker with a slight upward arcing motion.  As the chain falls out of the beaker onto the floor the arc should be maintained by the motion of the chain.

The fan motor and pulley version uses a continuous loop of chain.  Turn the fan onto the medium setting.  Use the 1/2 inch PVC rod to modify the shape of the rotating loop.  Notice how the chain will retain this modified shape, twist, or loop for a considerable period of time.

  • J. Pantaleone and R. Smith, "A Bullet-Block Experiment that Explains the Chain Fountain", TPT, Vol. 56, #5, May 2018, p. 294.
  • Wojtek Dindorf, "Tiny Chain Fountain", TPT, Vol. 54, #5, May 2016, p. 320.
  • Dan MacIsaac, "Understanding the Chain Fountain", TPT, Vol. 54, #5, May 2016, p. 318.
  • James Gorman, "A Startling Video, Explained", The New York Times, 03/04/2014.
  • Niel A. Dowie, "2. Dynabrolly", Vacuum Bazookas, Electric Rainbow Jelly and 27 Other Saturday Science Projects, p. 14 - 20.

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