Demonstrations

Thermal Properties of Rubber

Code Number :	4A30.80
Disclaimer:	Reprinted by permission of Dick Berg, University of Maryland, for use on this website. The demonstrations contained and referenced herein are listed for the purposes of cataloging and describing physics demonstrations which should be conducted only under the direction of a trained instructional support professional or physicist. These demonstrations are not presented for the purpose of being conducted by persons unconnected to this Facility and/or persons not consulting with or being supervised by the recognized instructional support professional or physicist and his/her staff. The University is responsible only for those demonstrations carried out using its own equipment using established safety and scheduling policies, and bears no responsibility for those choosing to use this source material for their own purposes. All demonstrations described and contained herein are public domain, and can also be found in reference materials in libraries, bookstores, and electronic sources. Further information regarding legal liability in use of demonstrations and labs will be found on the web site Injuries in School/College Laboratories in USA. The University of Iowa Disclaimers: University of Iowa Disclaimer All Rights Reserved..
Condition :	Excellent
Principle :	Expansion/Contraction
Area of Study :	Heat & Fluids
Equipment :	Thermal Properties Demo, Infrared Heat Lamps (2), Heat Gun (optional), Large Rubber Bands.
Procedure :	Set the Thermal Properties Demo Unit up as shown. The lightweight mass goes with the spring and the heavier mass with the rubber band. The rubber band will have to be stretched several times before hanging or until the pointers are about opposite each other. A small difference can be overcome by moving the rods the spring and/or the rubber band hang from. Move the scale up or down to the desired setting. Turn on the heat lamps. The spring will stretch about 1 cm and the rubber band will shrink up to 2 cm. It is important that the heat lamps are closest to the spring. The heat gun may be used in place of the heat lamps but the air movement may make the pointers move violently if you are not careful.

References

Mark I. liff, "Polymer Physics in an Introductory General Physics Course", TPT, Vol. 42, # 9, Dec. 2004, p. 536.

Tom Southworth, "Potential Energy Analysis of a Bow," TPT, Vol. 28, # 1, p. 42, (January 1990).

Bruce Denardo and Richard Masada, "Rubber Hysteresis Experiment," TPT, Vol. 28, # 7, p. 489 (October 1990).

D. Easton. "Hooke's Law and Deformation." TPT, Vol. 25, # 8, p. 494, (November 1987).

J. H. Weiner, "Entropic Versus Kinetic Viewpoints in Rubber Elasticity", AJP, Vol. 55, # 8, Aug. 1987, p. 746.

Hm- 4, 5: Freier and Anderson, A Demonstration Handbook for Physics.

M- 438: "Rubber Band & Bungee Cord," DICK and RAE Physics Demo Notebook.

H- 054: "Rubber Band," DICK and RAE Physics Demo Notebook.

C.L. Stong, "Concerning Experiments with Rubber and How to Re-Create a Classical Electrostatic Generator," The Amateur Scientist, (June, 1960).

Walpole, "Shrinking Rubber," 175 Science Experiments, p. 119.

Neil A. Downie, "Electronic Elastic", Ink Sandwiches, Electric Worms and 37 Other Experiments for Saturday Science, p. 198.

Mail Questions and Comments to: Dale Stille