2C20.45 - Attracting Balls or Sheets

Code Number:
2C20.45
Demo Title:
Attracting Balls or Sheets
Condition:
Good
Principle:
Coanda and Air Stream Around a Circular Object
Area of Study:
Heat & Fluids
Equipment:
Hanging Balloons or Balls.
Procedure:

Hang two balloons or balls so that there is a narrow gap between them. Blow a stream of air between the two balloons and watch as the balloons move toward each other.

References:
  • Clifford Swartz, "Bernoulli and Newton", TPT, Vol. 41, #4, Apr. 2003, p. 196.
  • Harold Cohen and David Horvath, "Two Large-Scale Devices for Demonstrating a Bernoulli Effect", TPT, Vol. 41, #1, Jan. 2003, p. 9.
  • "F-235. Two Light Bulbs on Strings", Dick and RAE Physics Demo Notebook, 1993.
  • Charles Vivian, "Blowing the Air Away", Science Experiments & Amusements For Children, p. 65.
  • Janice VanCleave, "In Not Out", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 35.
  • Robert Ehrlich, "H.13. Fan Below Two Vertical Pieces of Paper", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 107 - 108.
  • Jearl Walker, "Two Boats Drawn Together", The Flying Circus of Physics", p. 137.
  • Cy Tymony, "Air Pressure Demonstration V", Sneakiest Uses for Everyday Things", p. 25.
  • Cy Tymony, "Air Pressure Demonstration IV", Sneakiest Uses for Everyday Things", p. 24.
  • Martin Gardner, "Three for Bernoulli", Science Tricks, p. 19.
  • Julius Sumner Miller, Q119 & A119, Millergrams II – Some More Enchanting Questions for Enquiring Minds, p. 14 & 78.
  • David Kutliroff, "74. Air Streams Do Strange Things", 101 Classroom Demonstrations and Experiment For Teaching Physics, p. 162.






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