Demonstrations

Thermal Convection of a Liquid Demo

Code Number :	4B20.10
Disclaimer:	*Disclaimer* These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist. The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose. The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources. Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks. These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage. Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.
Condition :	Good
Principle :	Thermal Convection in a Fluid
Area of Study :	Heat & Fluids
Equipment :	Convection tube (glass, square-shaped), Ink or Food Coloring, Bunsen Burner, Water.
Procedure :	Fill the tube with water leaving enough room for several ml of coloring. Care is needed to see that undue strain is not put on the glass assembly when moving. The fastest convection is obtained when the burner is placed towards the corners of the apparatus. Quite a bit of coloring is needed to overcome dilution during convection. Note: Plexiglas will melt at around 300 degrees F. Be careful in your positioning of the Bunsen burner.

References

S. Velasco, J.A. White, F.L. Román, "Cooling of Water in a Flask: Convection Currents in a Fluid with a Density Maximum", TPT, Vol. 60, # 1, January 2010, p. 60.

Richard J. Bohan and Guy Vandegrift, "Temperature - Driven Convection", TPT, p. 76, Vol. 41, # 2, Feb 2003.

Albert A. Bartlett, "The Curious Case of the Well-Behaved Shower Curtain", TPT, Vol. 34, # 7, p. 444, Oct. 1996.

Edward J. Carlone, "Convection Demonstrator", TPT, Vol. 21, # 7, p. 464, Oct. 1983.

Hc- 2: Freier and Anderson, A Demonstration Handbook for Physics.

H-160: "Liquid in Loop - Candle in Box", DICK and RAE Physics Demo Notebook.

Tik Liem, "The Confused Bottles", Investigation to Science Inquiry, pp. 206.

David Kutliroff, "66, Convection Currents Made Visible with a Dye in a Glass Tube Filled with Water", 101 Classroom Demonstrations and Experiment For Teaching Physics, p. 146.

Janice VanCleave, "27, One Will One Won't", Teaching the Fun of Physics, p. 43.

Ron Hipschman, "Convection Currents", Exploratorium Cookbook III, p. 180.1 - 180.4.

"Convection Currents", Science Snackbook, p. 28.1 - 28.2.

Janice VanCleave, "Curls", 201 Awesome, Magical, Bizzare, & Incredible Experiments, p. 86.

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