Compares various methods of defining derived quantities, arguing for a definitional formula using base or fundamental units in a word equation, or symbol-equations with the symbols explained. Suggests that fundamental units be defined operationally or left regarded as intuitive as in the case of length and time. (JM)

Briefly describes the application of thermodynamics (system at equilibrium) to the study of the extraction of metals from their oxides (dynamic situation). It is more relevant to study the temperature variation of the equilibrium constants of the reaction than to study the free energy approach. (Author/SK)

Suggests an approach to understanding the integrals associated with teaching electricity and magnetism at the college level. Categorizes integrals that are commonly used, explains the significance of paired usage and presents a method for introducing concepts. Provides a review of symbols and for integrals in college textbooks. (CW)

Considers several aspects of quantitative relationships involved in learning physics. Includes discussions of proportionality, various kinds of equality, and the need for generality. Argues that clear distinctions are necessary if the physics curriculum is to be examined with regard to pupil outcomes. (TW)