Presents seven notes on new equipment, techniques, or materials of interest to teachers of physics. A circuit of a low-cost computer terminal to audiovisual device interface, and a demonstration of the buoyancy of air are among notes presented. (HM)

Describes some undergraduate laboratory experiments in acoustics which involve the analysis of speech and musical instrument sounds and the general analysis of the frequency range of complex sounds. (HM)

An experiment in which both Raman-Nath and Bragg diffraction of light by acoustic waves in water are observed in the sound frequency range from 5 to 45 MHz. The apparatus consists of a laser, light detector, rf power source, quartz transducer, and homemade water cell. (Author/DF)

Provides an annotated list of books, textbooks, and films on superfluid helium. Also lists research reports/reviews arranged by category, including among others, early history, microscopic understanding, ions in helium, helium in rotation, vortices and quantization, helium films and constricted geometrics, persistence flow, and superfluid helium…

Describes an experiment which makes use of a number of concepts from geometrical optics. The apparatus and method which is intended for students in elementary college physics classes are included. (HM)

Describes effects which produce the semidiurnal tidal bulges, using elementary methods, without reference to fictitious forces and without recourse to a potential. (Author/HM)

Presents an experiment on the bending of light in a medium with a continuously varying index of refraction. Several theoretical approaches for the analysis of this experiment, designed for college physics students, are also presented. (HM)

Describes an air track experiment which involves a massive particle incident on a fixed wall with a light particle trapped in between. An analysis for this experiment, which is intended for junior and senior college students, is also included. (HM)

Presents four notes that report new equipment and techniques of interest to physics teachers. These notes deal with collosions of atoms in solids, determining the viscosity of a liquid, measuring the speed of sound and demonstrating Doppler effect. (HM)

Discusses parametric oscillators and parametric instability. A simple, easy-to-construct system which exhibits parametric instability is presented. The two lowest-order resonances are described and analyzed in detail. The analysis stresses the physical and intuitive aspects of the problem. (Author/HM)

Discusses the oscillatory motion of a mass on a spiral (nonhelical) spring, and calculates the lowest eigenfrequency and the associated effective spring mass for a range of values of the attached mass. Analytic and numerical comparisons are made to the helical spring problem. (HM)

Describes an apparatus that offers a very lucid demonstration of Poisson statistics as applied to electrical currents, and the manner in which such statistics account for shot noise when applied to macroscopic currents. The experiment described is intended for undergraduate physics students. (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)