The diffraction of a full thermal atomic potassium beam by a single slit was observed. Four experimental diffraction patterns were compared with that predicted by de Brogtie's hypothesis and simple scalar Fresnel diffraction theory. Possible reasons for the differences were discussed. (LC)

Describes the computer generation of random and regular arrays of apertures on photographic film and their applications for classroom demonstrations of the Fraunhofer patterns produced by simple and complex apertures, Babinet's principle, resolution according to the Rayleigh criterion, and many other aspects of diffraction. (LC)

Synthesis and polymerization of vinyl monomers that double as stabilizers against degradation of plastics by ultraviolet light has been accomplished. Potential applications include protection of photovoltaic cells in solar power plants. (Author/RE)

Polarization of laser light is discussed and the theoretical and experimental aspects of fluxes are considered. (Author/SK)

Develops a coordinate-free approach to Fresnel's equations for the reflection and refraction of light at a plane interface. Describes a graphical construction for finding the vector amplitudes of the reflected and transmitted waves. (Author/CS)

Describes a simple and inexpensive way to construct two small growth chambers for studying phototropism in the science classroom. One chamber is designed to illustrate how plants grow around obstacles to reach light and the other to illustrate directional light responses. (HM)

Presents an activity that uses phosphorescent stars to help students understand the wave and particle nature of light. Discusses star phosphorescence, the emission spectrum of the stars, and the photoelectric effect. (DDR)

Describes an experimental approach to determining the speed of light in water using some simple observations and Fermat's principle. Enables students to integrate mathematical techniques and encourages mathematical exploration in which the students have control over what mathematics and technology to use and when to use them. Presents extensions…

Describes an ongoing project, the Cosmic Ray Observatory Project (CROP), being conducted by the University of Nebraska in partnership with several high schools. Each school group has installed cosmic ray detectors, and initial activities have included calibrating equipment, gathering preliminary data, and learning about cosmic ray showers. Aims to…

Discusses the biochemical mechanisms related to photosynthesis. Describes a water-oxidizing clock generating a molecule of oxygen with every four ticks. Lists four references. (YP)

Describes an exercise that allows the measurement of the sizes of biological samples by means of the diffraction of light. (JRH)

Provides activities for the study of light as a theme for December, which encompasses Christmas, Hanukkah, and Kwanzaa. Includes science activities and suggested books for children and teachers. (HTH)

Describes how students in an introductory physics and astronomy lab used computer and data interface units to sample a 15 second portion of a prerecorded audiotape of two broadcast stations to measure the speed of light. (CCM)

Describes how to teach the light spectrum to students using hands-on activities in a physical science class at the middle school level. Explains how to build a spectroscope and lists required materials. Provides an internet address for sciLinks. (YDS)