The often observed and misunderstood phenomenon of movement of black and white vanes in toy radiometers under illumination is discussed in a generalized non-mathematical manner. Effects of light pressure, low gas density, friction, heat, and motion are illustrated. (JM)

Discusses a strategy for presenting science concepts via activities which include personal, self-sensitizing frames of reference for students. Examples include force and temperature measurement. (JM)

Describes an apparatus designed to demonstrate vortical flow of a fluid. The apparatus consists of a transparent acrylic cylinder, with a drain hole, and mounted so that it can be rotated about its axis at speeds up to 1000 rpm. Experimental observations with water as the fluid under study are reported. (LC)

Thermodynamic availability functions can be viewed graphically, providing valuable unexpected insights into the nature and meaning of the functions. As a demonstration, the following question is explored and discussed: "What is the maximum work a system can perform in moving into equilibrium with the temperature and pressure of its…

A study examined the effectiveness of two types of canoe paddles in marathon canoe racing. Results of the study indicated that the angled paddle produced significantly greater boat speeds than did the straight paddle. (JN)

Outlines advantages of and provides background information, procedures, and typical student data for an experiment determining rate of hydration of p-methyoxyphenylacetylene (III), followed by nuclear magnetic resonance spectroscopy. Reaction rate can be adjusted to meet time framework of a particular laboratory by altering concentration of…

The lack of parallelism between the force and acceleration vectors has several apparently paradoxical consequences that have been recently examined. This article uses a different and more general mode of analysis than previous authors to derive quite general, rather than particular, results. (Author/SK)