Two equipment systems are described: mechanical start-stop gates for air tracks, and a large-scale magnetic induction demonstration. (CS)

Articles describing construction of an inexpensive spectrograph, improving focusing of Polaroid cameras, use of space satellites for instruction, and construction of an optics demonstration platform. (RH)

Describes the following: a low-pressure sodium light source; a design of hot cathodes for plasma and electron physics experiments; a demonstration cart for a physics of sound course; Bernoulli force using coffee cups; a spark recording for the linear air track; and a demonstration of the effect of altering the cavity resonance of a violin. (GA)

Describes three pieces of scientific apparatus and their demonstrational use: a high temperature apparatus for positron annihilation studies, a digitally synthesized classroom variable star, and a demonstration of plasma laser-beam focusing using paint stripper flames. (GA)

This collection of notes describes (1) an optoelectronic apparatus for classroom demonstrations of mechanical laws, (2) a more efficient method for demonstrated nuclear chain reactions using electrically energized "traps" and ping-pong balls, and (3) an inexpensive demonstration for qualitative analysis of temperature-dependent resistance. (CS)

Describes experiments and apparatus to: (1) allow astronomy students to test resolution limit of their eyes at several wavelengths; (2) analyze laser mode phases by interferometry; (3) demonstrate a Cartesian diver with an overhead projector; and (4) generate conical beams of light for smoke-chamber demonstrations. (JN)

Describes the following: an electric circuit for an expensive photometer, an amplifier circuit capable of demonstrating many aspects of behavior of free and driven oscillators, and finally a projection recording system which uses an unmodified XY or XT recorder and a separate overhead projector. (GA)

Describes a method for performing a thermodynamic "ice bomb" demonstration which is faster, simpler, and cheaper than commercially available demonstration devices. (SL)

Describes (1) a rippler assembly which makes use of a loud speaker and a stroboscopic light source designed for this application; and (2) an experiment using a force table that has been modified for a capstan experiment. (JN)

Describes an intelligent lightbulb, an optelectric feedback circuit which bridges the conceptual gap between manual and all-electric servos. The circuit is simple and easily understood in dc terms. Also describes a device for demonstrating wave motion constructed with plastic soda straws. (Author/SK)