Describes a demonstration in which the pattern on a rotating turntable can be affected by humming and adjusting the pitch of the hum. At some frequency, if conditions are right, the pattern can be stopped, or "strobed." Also describes a way to introduce humor into physics instruction. (JN)

Experiments which illustrate the effect of humidity on human hair and on paper are described. Also described are two ways to make a hygrometer. These methods were found in a series of British television programs (also available in the United States). Comments on the programs are included. (JN)

Quantifies the interaction of a tennis ball and a tennis court surface. Also shows how, by making a few simple measurements, one court surface can be compared to another court surface. (JN)

Provides the rationale for and examples of experiments designed to test the stability of protons and bound neutrons. Also considers the unification question, cosmological implications, current and future detectors, and current status of knowledge on proton decay. (JN)

Discusses children's conceptions of dynamics, comparing them to those of scientists and examining how they are acquired. Also discusses alternative aims of teaching dynamics at the elementary and junior high school levels, providing instructional strategies to achieve these aims. (JN)

Examines (in the form of a hypothetical dialog between a teacher and a student) the nature of the mantle and the spectral content of the glow which lights up both beam and mantle. These phenomena are associated with excitation of helium gas in the presence of electromagnetic and electrostatic fields. (JN)

Describes how a planetarium was constructed on the ceiling of a traditional physics laboratory. Similarities and differences between the "poor man's" planetarium and other planetariums are noted. (JN)

Procedures for demonstrating rainbows in the classroom are provided. Materials required include a clear plastic box (the size of a shoebox), water, and an overhead projector. Also tells how to make a rainbow on the chalkboard using colored chalk. (JN)

Describes an apparatus which demonstrates the stability of equilibrium of multidimensional objects and helps students to understand the concept of a lever arm. Also describes an alternative to the standard black, mercury "student cell" used as a reference voltage for calibrating a slide-wire potentiometer. (JN)

Clarifies two concepts of gravity--those of a fictitious force and those of how space and time may have geometry. Reviews the position of Newton's theory of gravity in the context of special relativity and considers why gravity (as distinct from electromagnetics) lends itself to Einstein's revolutionary interpretation. (JN)

Describes a college-sponsored physics competition which benefits both high school physics teachers and students. The competition (a paper/pencil examination) is open to students of all abilities and provides an opportunity for teachers to meet and exchange ideas on a yearly basis. (JN)

Reports results of a 1983 national survey which determined the time devoted to teaching major physics content areas; subtopics in each area; equipment students saw and used; principle textbook used; and school/physics enrollments. Indicates that the data obtained can be used to establish guidelines in developing the Physics Achievement Test. (JN)

Today students routinely measure the acceleration due to gravity (g) with strobes and high-speed photography. However, it is possible to measure g using equipment and reasoning available to Galileo. Such an experiment (and the equipment needed) is described. (JN)

Presents several optical illusions which can be used to demonstrate the principles of geometrical optics. Procedures needed to accomplish the demonstrations are included. (JN)

Evaluates the Measurement Module (TEL-Atomic, Incorporated), a real time data capture and display instrument which (according to the manufacturer) was designed primarily for use in demonstrations. Includes comments on the module's specifications and features, software, documentation, and student laboratory use. The module is compatible with Apple…