Describes a method of network analysis that allows avoidance of Kirchoff's Laws (providing the network is symmetrical) by reduction to simple series/parallel resistances. The method can be extended to symmetrical alternating current, capacitance or inductance if corresponding theorems are used. Symmetric cubic network serves as an example. (JM)

Discusses the physics of liquid crystal displays (LCD) which is based on polarizing properties of crystals controlled by electric command. Production of alphanumerics, display control, and input are considered. (JM)

Provided is a review of a high school/college level computer program (for Apple microcomputers) which consists of six simulations designed to introduce students to simple harmonic motion. Includes a discussion of the six simulations and such information as time needed, probable classroom use, source, and current cost. (JM)

Suggestions are provided for demonstrating vector cross product and vector dot product using manipulatives. Also provides a method for producing quick and inexpensive diffraction slits and ideas for demonstrating two-dimensional diffraction. (JM)

Describes the construction of a small (portable), inexpensive, and easy to build Foucault pendulum. Includes photographs of the apparatus, a schematic of the electrical circuit used, and discussion of the amount of accuracy to be expected during classroom investigation. (JM)

In response to a question, "Why not use a magnetic or electric field to deflect light?," reviews the relation between electric charge and electric/magnetic fields. Discusses the Faraday effect, (describing matter as an intermediary in the rotation of the place of polarization) and other apparent interactions of light with electric/magnetic fields.…

Points out textbook errors or discrepancies which are confusing or unclear in describing the photon. Cites specific texts and the particular point of confusion in each one. (JM)

Discusses the construction of various types of physics equipment from laboratory "bits and pieces" (parts of discarded/unusable equipment). Includes comments on constructing improvised equipment from similar bits and pieces in schools in Peru and the Caribbean. (JN)

Describes two kinematics/dynamics programs (Apple II) easily adaptable to other microcomputers. Kept simple, the programs allow teacher/student to control forces acting on a particle by introducing force laws in programs or by using game paddles/joystick. Discusses equations used and provides program listings. (JN)

Use of diagnostic testing (for mathematics skills) and multiple-choice, computer-graded homework in reducing dropout from general physics is discussed. Indicates that these strategies were successful without sacrificing academic or grading standards. Includes list of topics on the diagnostic math test and sample homework problem set (in…

Describes an experiment enabling students to apply concept of diffraction, determine limits of their color perception, learn how to measure wavelength with a simple apparatus, observe continuous and line spectra, and associate colors with corresponding wavelengths. The homemade diffraction-grating spectrometer used is easily constructed. (JN)

Students' cars and wristwatches are used as "apparatus" to introduce and demonstrate Newton's second law of motion. Forces acting on cars are discussed and typical student data (for different makes of cars) are provided. Data could also be used in discussions of work, horsepower, efficiency, and energy cost. (JN)

When salt (NaCl) is introduced into a colorless flame, a bright yellow light (characteristic of sodium) is produced. Why doesn't the chlorine produce a characteristic color of light? The answer to this question is provided, indicating that the flame does not excite the appropriate energy levels in chlorine. (JN)

Provides an explanation for the observed motion of frisbees, can lids, "clay pidgeons," and flat stones when these objects are thrown through the air. Explanation focuses on forces (gravity and air), torque, and gyroscopic precession. (JN)

Describes inexpensive method of determining harmonic content of a repetitive signal such as a sound wave and demonstrations of the precession of a bicycle wheel and inversion shadows on the retina. Also describes a resonance demonstrator (made from scrap material) driven by a portable jigsaw. (JN)