Examines, in three experiments, infant sensitivity at 20, 30, and 36 weeks of age to 3-dimensional structure of a human form specified through biomechanical motions. Findings are interpreted as suggesting that infants, by 36 weeks of age, are extracting fundamental properties necessary for interpreting a point-light display as a person. (Author/BE)

An elementary physical model of cone receptor cells is explained and applied to complexities of human color vision. One-, two-, and three-receptor systems are considered, with the later shown to be the best model for the human eye. Color blindness is also discussed. (DH)

Describes a simplified method of calculating the speeds necessary to cause large relativistic changes and to determine the magnitudes of physical quantities as an object approaches the speed of light. Provides equations and two completed example problems. (JM)

Discusses how the caustic by reflection is formed. Indicates that the phenomenon can be demonstrated by showing the reflection of the light from a distant point source from the inner curve of a polished hoop of metal (such as a wedding ring). (JN)

Describes three demonstrations used in the Chicago Museum of Science and Industry polarized light show. The procedures employed are suitable for the classroom by using smaller polarizers and an overhead projector. Topic areas include properties of cellophane tape, nondisappearing arrows, and rope through a picket fence. (JN)

Presents a nonmathematical approach to help students understand that there are two types of coherence and to associate coherence as a property of the illumination at an object itself. The approach also lends itself to an introduction to the Fourier approach for analyzing imaging systems. (JN)

Presents the listing (TRS-80) for a computer program which derives the relativistic equation (employing as a model the concept of a moving clock which emits photons at regular intervals) and calculates transformations of time, mass, and length with increasing velocities (Einstein-Lorentz transformations). (JN)

Provides background information on and experiments for determining the spectra of streetlights. Procedures for taking photographs of the spectra produced are included as well as discussions of sodium and mercury spectra. (JN)

Discusses three theories used to explain the interaction of electromagnetic radiation with matter: the multiphoton theory, the cascade theory, and the effective photon theory. (MLH)

The information provided in this booklet is meant to give the necessary background information so that the science of black holes can be taught confidently to elementary students. The featured activities can be used to engage and excite students about the topic of black holes in different disciplines and in a number of ways. Activities include:…

Describes new applications being found for solar energy as a result of technical advances and a variety of economic and social forces. Discusses the basic requirements for a solar climate control system and outlines factors that should stimulate greater use of solar energy in the near future. (JR)

Presents a brief historical account of Michelson's invention of his interferometer with some subsequent ingenious applications of its capabilities for precise measurement discussed in details, including the experiment on detrmination of the diameters for heavenly bodies. (CC)

Discusses the nature of virtual images and how they can be plotted and used to reveal important relationships between objects and their mirror reflections. Describes some applications of virtual images in the theater and classroom. (JR)

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)