Demonstrations

Electrical Equivalent of Heat

Code Number :	5F15.10
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 :	Good
Principle :	Relationship between Thermal and Electrical Energy
Area of Study :	Electricity & Magnetism
Equipment :	Countdown timer, Insulated flask, 250 Watt heater, AC current projection meter, Ring stand, Digital thermometer, 2 Digital Meters (amperage and voltage), Cord for Multimeter, Beaker and Water.
Procedure :	Set up as shown and by running the experiment for a set amount of time, measuring the voltage and current, and the temperature rise, you should be able to calculate the electrical equivalent of heat.

References

Thomas B. Greenslade, Jr. "Nineteenth - Century Measurements of the Mechanical Equivalent of Heat." TPT, Vol. 40, # 4, p. 243, (April 2002).

Ronald F. Gleeson, Melvin Deak, "Joule's Law Experiment", TPT, Vol. 19, # 2, Feb. 1981, p. 119.

Brother T. G. Bullen, "Alternative setup for Joule's Law", TPT, Vol. 19, # 5, May 1981, p. 280.

Frank G. Karioris, "Inexpensive Immersion Heater", TPT, Vol. 12, # 9, Dec. 1974, p. 573.

Samuel C. Dickienson, "Relating Heat and Electrical Units with Immersion Heaters", TPT, Vol. 10, # 5, May 1972, p. 268.

T.E. Neil and P.D. Schulze, "Mechanical Equivalent of Heat: Electrical Method by Vaporization of Liquid Nitrogen," AJP, Vol. 54, No. 5, May 1986.

Eh-3, He-4: Freier and Anderson, A Demonstration Handbook for Physics.

Robert Ehrlich, "Conversion of Electrical to Thermal Energy," Turning the World Inside Out, p. 152-153.

Mail Questions and Comments to: Dale Stille