2C20.70 - Magnus Effect - Loop the Loop

Code Number:
Demo Title:
Magnus Effect - Loop the Loop
Bernoulli's Principle
Area of Study:
Heat & Fluids
Rubber Band Chain and 2 Styrofoam Cups Taped Together at the Bottoms.

Wind the rubber band chain around the middle of the cup apparatus.  When winding be sure to stretch the rubber band.  Stretch the end of the rubber band ahead of the cup and let fly.  The cup will start to spin and the spinning action will send it into a curve that looks like a loop de loop.

  • Rod Cross, "Measuring the Effects of Lift and Drag on Projectile Motion", TPT, Vol. 50, #2, Feb. 2012, p. 80.
  • Dick Minnix, "The Spin on Baseballs or Golfballs", TPT, Vol. 18, #4, Apr. 1980, p. 308.
  • Nicolas Plihon, Gauthier Legrand, Francis Pagaud, Arsene Chemin, Jeremy Ferrand, Nicolas Taberlet, et al, "The Physics of Magnus Gliders", AJP, Vol. 89, #9, Sept. 2021, p. 843.
  • Roger L. Schneider and Glenn M. Schmieg, "Bernoulli Cups", AJP, Vol. 47, #2, Feb. 1979, p. 200.
  • Bruce Yeany, "Cup Flyers!", Popular Mechanics, May 2018, p. 104
  • D. Rae Carpenter Jr. and Richard B. Minnix, "F-265.Curving Cups - Mailing Tube", DICK and RAE Physics Demo Notebook, 1993.
  • Donna Berry Conner, "The Spin on Baseballs or Golfballs", A Potpourri of Physics Teaching Ideas, p. 50.

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