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Colorado State University

Csu: Model of Basic Otto Cycle

For Students 9th - 10th
This site from the Colorado State University discusses the Otto cycle of a car engine. Includes a highly mathematical treatment of the efficiency of such engines. Includes a link to a java applet investigating the efficiency of such...
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University of Sydney (Australia)

Thermal Physics Module: Refrigerators and Heat Pumps [Pdf]

For Students 9th - 10th
Refrigerators and heat pumps are described. Their operation is explained and the variables which improve their efficiency is discussed.