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 research projects and experiments in graphic design conducted at a number of colleges and universities. (GT)

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 straightforward vertical fall experiment using a badminton shuttlecock, a tape measure, and a millisecond timer. The effects of air resistance are important and directly measurable. The experimental data best fit a predictive model which assumes a resistive force quadratic in the instantaneous speed of the falling object. (GS)

The emphases of this investigation were to outline procedures to assess the effectiveness of instructional materials and to examine those procedures. Methods for determining sample size, constructing instruments, and modifying data are described. (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.…