Errors found in a common physics experiment to measure acceleration resulting from gravity using a linear air track are investigated. Glider position at release and initial velocity are shown to be sources of systematic error. (CW)

Introduces three laboratory exercises which develop an understanding of principles of mechanics by using examples of bicycle operation: Newton's laws, statics and dynamics, and energy relationships. Describes related theory and laboratory procedures with diagrams and pictures in each exercise. (YP)

Describes the layout, working principle, and uses of an ultrasonic interferometer for demonstrating the impact of the motion of the medium upon wave propagation. Suggests some technical improvements of the interferometer. (YP)

Discussed are selected application and future trends in supercritical fluid chromatography (SFC). The greatest application for SFC involves those analytes that are difficult to separate using GC or LC methods. Optimum conditions for SFC are examined. Provided are several example chromatograms. (MVL)

Discussed is a method of measuring the coefficient of linear expansion of a solid. Getting many data points, using a computer program using the least square fit technique, and modifying the apparatus are described. (YP)

Discusses the use of an overhead projector for the deflection of a vertical image to a screen. Describes three demonstrations: magnetizing of a steel ball bearing and paper clip; convection currents of a hot liquid within a cold liquid; and oscillation of concentrated salt solution into fresh water. (YP)

Described are three physics experiments: (1) "Holographic Prism"; (2) "Teaching about Energy with the Gravicar"; and (3) "The Coherer." In each experiment, a brief description of the experiment devised is provided with diagrams and references. (YP)

Explained is a representation of the three categories of spectra. Discusses what a lesson on spectra should include, background information, and equipment needed. Provided is a diagram of an absorption box. (RT)

Presents an activity that demonstrates the physical and chemical changes that occur during the operation of a wet cell battery as it produces an electrical current. Provides instructions for the lesson. (MDH)

Describes the federal legislation introduced in 1991 that provides formula grants to states to purchase elementary science equipment. The purchases are to be matched by local education agencies and coordinated with hands-on laboratory activities. (MDH)

Computer interfaced electrostatic charge sensors allow both qualitative and quantitative measurements of electrostatic charge but are quite sensitive to charges accumulating on modern synthetic materials. They need to be used with care so that students can correctly interpret their measurements. This paper describes the operation of the sensors,…

Analytical and experimental methods are used to determine the natural frequencies and mode shapes of Aluminum 6061-T651 beams with rectangular and circular cross-sections. A unique test stand is developed to provide the rectangular beam with different boundary conditions including clamped-free, clamped-clamped, clamped-pinned, and pinned-pinned.…

The hearing reported in this document focused on H.R. 4726, a bill concerned with improving the facilities and instructional equipment available at science-technology centers, two-year colleges, and other non-profit institutions engaged in informal and formal education in science and technology. Witnesses from three agencies (National Aeronautics…

Most children become excited about science because they can do something and because they can watch the results. These are some of the answers most elementary school students tell you when they are asked about science class. It has been substantiated by decades of research that experiential experiences are exciting and remembered, visual and…

Recognizing that a crisis exists in engineering education, several state professional engineering societies have taken the lead in identifying and helping to solve problems related to engineering education on a state level. The National Society of Professional Engineers (NSPE), believing that NSPE state societies are ideally structured to assume a…