Historically, classical thermodynamics was developed during attempts to improve the efficiency of steam engines. Those investigations led to the well-known zeroth, first, and second laws of thermodynamics. Although these laws are presented independently, linkages between the zeroth and second laws have been pointed out in the physics teaching…

The January 2013 Physics Challenge for Teachers and Students has some features that are surprising and worth a closer look. The problem concerns a Carnot-cycle refrigeration unit operating inside a tent. It achieves dynamic equilibrium with a freezer ("cold") compartment temperature of T[subscript C] = 13°C, tent temperature of…

In 2009, President Obama proposed an initiative to decrease our country's energy consumption and dependence on fossil fuels. One key to this plan was to decrease the amount of energy used to heat and cool our homes through government incentives. The EPA estimates that the average American household spends over $1000 annually for heating and…

The scientific method is arguably the most reliable way to understand the physical world, yet this aspect of science is rarely addressed in introductory science courses. Students typically learn about the theory in its final, refined form, and seldom experience the experiment-to-theory cycle that goes into producing the theory. One exception to…

The standard formulation of energy conservation involves the subsidiary ideas of kinetic energy ("KE"), work ("W"), thermal energy, internal energy, and a half-dozen different kinds of potential energy ("PE"): elastic, chemical, nuclear, gravitational, and so forth. These quantities came to be recognized during the centuries over which the…

Discusses the potential and feasibility of future widespread exploitation of the vast geothermal energy resources, that could greatly reduce the need for other forms of energy resources. (GA)

Discusses the feasibility of solar housing for northern latitudes. (SL)

Presents a framework for teachers to use the thermodynamic system of popping corn to generate student interest. Examines the popping mechanism and the role of steam in, the heat required during, and the energy efficiency of the popping process. (MDH)