2A15.21 - Catenoid/Catenary

Code Number:
2A15.21
Demo Title:
Catenoid/Catenary
Condition:
Excellent
Principle:
Surface Tension
Area of Study:
Heat & Fluids
Equipment:
2 Hoops (One Slightly Smaller than the Other) and Soap Bubble Solution.
Procedure:

Dip the hoops into the soap bubble solution and position so that one hoop is inside the other.  Pop the film that is in the middle of the smaller hoop.  Slowly draw the two hoops apart and the soap film should show the minimum energy catenoid.

References:
  • Thomas B. Greenslade Jr., "Keeping Our Readers in Suspense", TPT, Vol. 56, #5, May 2018, p. 276.
  • F. Behroozi, "In Praise of the Caternary", TPT, Vol. 56, #4, Apr. 2018, p. 214.
  • Thomas B. Greenslade Jr., "An Old Favorite: The Noncircular 'Wheel'", TPT, Vol. 44, #4, Apr. 2006, p. 244.
  • James A. Flaten, "Curves of Constant Width", TPT, Vol. 37, #7, Oct. 1999, p. 418. 
  • Charles L. Adler, "Catenaries on the Computer: A Freshman Physics Assignment", TPT, Vol. 37, #4, Apr. 1999, p. 254.
  • Jeffrey R. Regester, "A Long and Bumpy Road", TPT, Vol. 35, #4, Apr. 1997, p. 232.
  • H. Richard Crane, "Three Intuition Teasers", TPT, Vol. 29, #9, Dec. 1991, p. 593.
  • R. D. Edge, "The Wobbler", TPT, Vol. 28, #2, Feb. 1990, p. 122.
  • George W. Ficken, "Catenary Curve Application", TPT, Vol. 16, #7, Oct. 1978, p. 487.
  • C. Criado and N. Alamo, "Solving the Brachistochrone and Other Variational Problems With Soap Films", AJP, Vol. 78, #12, Dec. 2010, p. 1400.
  • Robert O'keefe, "A Circular Caternary', AJP, Vol. 64, #5, May 1996, p. 660.
  • F. Behroozi, P. Mohazzabi, and J. P. McCrickard, "Remarkable Shapes of a Catenary Under the Effect of Gravity and Surface Tension", AJP, Vol. 62, #12, Dec. 1994, p. 1121.
  • Eli Honig, "New Wine into Old Bottles: A Nuptial Arch", AJP, Vol. 59, #5, May 1991, p. 472.
  • Harold S. Zapolsky, "A Simple Solution of the Center Loaded Catenary", AJP, Vol. 58, #11, Nov. 1990, p. 1110.
  • "M-837. Stand on Egg", DICK and RAE Physics Demo Notebook, 1993.
  • Tik Liem, "Fission and Fusion", Investigation to Science Inquiry, p. 188.
  • Jearl Walker, "2.122, Soap Bubble Shapes", The Flying Circus of Physics Ed. 2, p. 135.
  • Robert Ehrlich, "H.17. Water Bridge", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 111.

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