While entropy is often described as "disorder," it is better thought of as a measure of how spread out energy is within a system. To illustrate this interpretation of entropy to introductory college or high school students, several activities have been created. Students first study the relationship between microstates and macrostates to…

Students in introductory physics courses often don't study thermodynamics or thermodynamic events. If any thermal physics is taught in introductory courses (e.g., Physics 101 for Liberal Arts Majors), it usually involves the concepts of specific heat and various temperature scales. Seldom are the first and second laws of thermodynamics taught in…

The rapid compression or expansion of a gas in a plastic syringe is a poor approximation of an adiabatic process. Heat exchange with the walls of the syringe brings the gas to equilibrium in an amount of time that is not significantly greater than the length of the compression or expansion itself. Despite this limitation, it is still possible to…

This paper discusses a Fermi-problem exercise through which I take students in several of my college courses. Students work in teams, determining the average daily Caloric needs per person. Then they use insolation values to determine the size of a collection area needed to absorb the previously determined daily energy requirements. Adjustments to…

A pair of fine tweezers and a steady hand may well be enough to pick up a grain of sand, but what would you use to hold something hundreds of times smaller still, the size of only one micron? The answer is to use a device that is not mechanical in nature but that relies instead on the tiny forces that light exerts on small particles: "optical…

Emphasizes firewalking as a good illustration of basic concepts in thermodynamics. Describes the basic principles of firewalking and other factors including the cooling of the surface embers, moisture of the feet, thick skin on the feet, tolerance for pain, and other uncontrolled factors. (YP)

Photographs illustrate several principles of physics which can be observed in everyday situations. (CP)

Lists several ideas for experiments for the amateur scientist to try or design. The list covers a wide range of topics; sound, mechanics, thermodynamics, fluids, optics, and electrostatics. (GA)

Photographs of snow covered buildings are used to illustrate thermal radiation from various types of structures and the effect of insulation on heat loss. (CP)

Suggests the use of a colorimeter in which heat produced is related to the amperage and voltage measured. In relating the quantities, a definition for voltage can be obtained. (CP)

Presents experiments that use the Mattel's Hot Wheels Top Speed toy set to show that work is a measure of energy transferred to or from a system. (JRH)

The effect of color on heat absorption ability is demonstrated using different color copper disks on a snow covered surface. (CP)