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)

Presents an experiment to illustrate mechanical resonance designed for use in lower division laboratories. The apparatus and procedure have been kept simple. The basic experiment yields measurements of amplitude versus driving frequency, but a fairly simple elaboration allows for measurements of phase lag as well. (Author/SK)

Compares between the component and the modules (system) approaches which are used to teach electronics at Croydon High School, Australia. The author presents some personal views from his experience of teaching both ways. (HM)

Discusses the use of toys to teach physics. Potential advantages and disadvantages of using toys in the physics classroom or laboratory in addition to some demonstrations and experiments that use balls, cars, and musical toys are also presented. (HM)

Describes how some experiments in physics can be presented in class using cheap materials. How to produce an electrostatic charge using a polythene bottle and how to make a tissue paper electroscope using a tin can are among the experiments described. (HM)

Describes an apparatus and procedure for conducting an undergraduate laboratory experiment to quantitatively study the Hall effect in a plasma. Includes background information on the Hall effect and rationale for conducting the experiment. (JN)

Describes an undergraduate experiment which measures the energy gap in silicon and germanium. Theory, procedure, and results of this experiment are included. (HM)

Provides information regarding the extra bands of color, termed supernumerary arcs, that sometimes accompany a natural rainbow. Several experiments are described that elucidate the phenomenon of supernumerary arcs, involving the illumination of a hanging water droplet with white light from a projector or monochromatic light from a helium-neon…

Describes and evaluates the fabrication of an easily constructed and inexpensive stop-flow system using commercially available components. (CS)

Describes a project on the application of the laser which aims to stimulate the interest of undergraduate students in applied physics and to demonstrate the interaction between light and ultrasonic waves by building a simple laser communication system. (SK)

Describes a method to detect the presence of microgram quantities of nearly any metal in samples of alloys, minerals, water, and air. This chemical-spot testing technique requires no elaborate equipment and can be done by an amateur. (SK)

Presents history, nature of evidence evaluated, and philosophical questions to justify the view that experiments on parity nonconservation were "crucial" experiments in the sense that they decided unambiguously and within a short period of time for the appropriate scientific community, between two or more competing theories or classes of theories.…

The motivation and interpretation of the Fizeau experiment are reviewed, and its status as a test of special relativity is discussed. It is shown, with the aid of a simplified, purely mechanical model of the propagation of light in matter, that the experiment actually cannot discriminate between Galilean and relativistic kinematics. (Author/SK)

Describes different evaluation techniques of student performance in the science laboratory. Evaluation techniques discussed include written reports, test items, practical tests, and observational assessment to evaluate both student performance and to promote development of specific skills. (DS)

Describes a nuclear debris collector which removes trace substances from the lower atmosphere during rainfall. Suggests that the collector could be implemented into courses at various educational levels and could result in developing a network for monitoring the geographical extent of nuclear contamination. (Author/SA)