Outlines the Cosmic Background Explorer (COBE) mission to measure celestial radiation. Describes the instruments used and experiments involving differential microwave radiometers, and a far infrared absolute spectrophotometer. (YP)

Described are three experiments on the photometric, Gaussian, and image-forming properties of a helium-neon gas laser. Details of the experimental method and typical calculations with diagrams and graphs are provided. (YP)

Describes a demonstration of the transmission of data signals from one microcomputer to another using an optical fiber line. Discusses the set-up method and demonstration steps for sending program and graphics. Provides a block diagram of the system and two circuit diagrams. (YP)

Explains the problem of analyzing a phase object, separating the contribution due to thickness variations and that due to refractive index variations. Discusses the design of an interferometer and some applications. Provides diagrams and pictures of holographic images. (YP)

Combines the PASCO Free Fall Adapter with a homemade timing sensor. Provides hints for successful operation of the timer and the Atwood Machine. (MVL)

Describes the use of geiger counters for scientific investigations and experiments. Presents information about background radiation, its sources and detection. Describes how geiger counters work and other methods of radiation detection. Provides purchasing information for geiger counters, related computer software and equipment. (MCO)

Presents two demonstrations to compare the differences between the screen reproductions of a bulb when using a converging lens and a pinhole and how that reproduction image reaches the observer's eye from multiple vantage points. (MDH)

Describes a theoretical development to explain the shadow patterns of an object exposed to an extended light source while held at varying distances from a screen. The theoretical model is found to be accurate in comparison with experimental results. (MDH)

Discusses the history of Rudolph Koenig's contribution to the development of acoustical apparatus. Contributions include the clock fork to determine absolute acoustic frequencies, a forerunner of the oscilloscope called the manometric flame, and an acoustic interference apparatus used in the Fourier synthesis of musical sounds. (MDH)

Describes an assignment and the results of having elementary school students design their own interesting and exciting science classroom environment. (PR)

Describes how practical science can be taught using locally-collected junk materials and encourages a new approach to science teaching in rural India. Emphasizes science relevant to the villages to which children will return to when they leave school. (DDR)

Describes how to build your own drop tower. Notes that these demonstrations are part of a portable and compact demonstration kit that fits entirely into a trunk, television and all. (CCM)

Presents detailed instructions and teaching tips for demonstrating resonance and the resulting fracture in a wine glass. (WRM)

Relays one school science technician's experiences in taking a course designed to improve and standardize technician credentials in the United Kingdom. (WRM)

A group of high school students (XII Liceum) in the framework of the Roland Maze Project has built a compact telescope of three Geiger-Muller counters. The connection between the telescope and a PC computer was also created and programmed by students involved in the Project. This has allowed students to use their equipment to perform serious…