4B20.38 - Thermal Convection of a Gas - Convection Currents

Code Number:
Demo Title:
Thermal Convection of a Gas - Convection Currents
Thermal Convection Currents
Area of Study:
Heat & Fluids
Convection Mobiles, Convection Lamp, 100 Watt Light Bulb, and Variac.

Turn on the convection lamp and the inner part should start to rotate giving views of different planets. Set the 100 watt light bulb under the convection mobiles and turn on. The mobiles should start to spin as the hot air rises.

Light the candle or place a smoking paper inside one side of the antique convection apparatus and observe the updraft and the downdraft sides.

  • R.D. Edge, "The Two-Cent Turbine or Magic Millwheel",  TPT, Vol. 26, #7, Oct. 1988, p. 468.
  • George W. Ficken, Jr., "Convection - Driven Oscillator", TPT, Vol. 20, #7, Oct. 1982, p. 469.
  • Carl Kenty, "The Calorotor: A Simple Heat Engine with Which the Motion of Individual Molecules may be Demonstrated", AJP, Vol. 35, #12, Dec. 1967, p. 1120.
  • George M. Hopkins, "Ascensional Power of Heated Air", Experimental Science, p 196.
  • Carson I. A. Ritchie, "The Spinning Snake", Making Scientific Toys, p. 105.
  • Charles Vivian, "Making an Air-Screw", Science Experiments & Amusements For Children, p. 4.
  • Martin Gardner, "The Twisty Snake", Science Tricks, p. 28.
  • Martin Gardner, "Psychic Motor?", Science Tricks, p. 27.
  • Janice VanCleave, "26, Spinning Spiral", Teaching the Fun of Physics, p. 42.
  • Janice Van Cleave, "58, Up Draft",  Earth Science for Every Kid, p. 130.
  • Janice VanCleave, "Up Draft", 201 Awesome, Magical, Bizarre, & Incredible Experiments, p. 78.
  • Shoma Kutasov, Physics Demonstrations, p. 67.
  • Sara Stein, "Draft Detector", The Science Book, p. 166.

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