2A15.10 - Ring and Thread

Code Number:
Demo Title:
Ring and Thread
Surface Tension
Area of Study:
Heat & Fluids
Soap Bubble Solution and Ring Frame with Thread Network.

Dip the ring frame with thread network into the soap bubble solution and remove. Hold up to the light and show that the thread network is limp because there is soap film both inside and outside of the thread loop. Break the bubble inside the loop and the thread immediately pulls into a circle due to surface tension from the outside bubble.

  • L.M. Gratton and S. Oss, "Soap, Colors, Holes, and Much More", TPT, Vol. 43, # 6, p. 338, Sept. 2005.
  • Ernest K. Chapin, "The Strange World of Surface Film", TPT, Vol. 4, # 6, Sept. 1966, p. 271.
  • Fi-13:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • George M. Hopkins', "Surface Tension", Experimental Science, Volume Two, p. 229.
  • R. W. Pohl, "(6)", Physical Principles of Mechanics and Acoustics, p. 174.
  • W. Bolton, "Surface Tension", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 21.
  • W. Bolton, "The Production of Foams", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 68.
  • Sara Stein, "Soap Circle", The Science Book, p. 167.
  • Tik L. Liem, "The Strong Soap Film", Invitations to Science Inquiry - Supplement to 1st and 2nd Ed. p. 45.

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