The moving pattern that appears on an oscilloscope screen is used to illustrate two kinds of wave motion and the relationship between them. Suggestions are presented for measuring wavelength, frequency, phase shift, and phase velocity in this college-level laboratory exercise. (DH)

Describes a lecture demonstration which illustrates changes in the visible spectra of oxygen transport proteins upon reversible oxygen binding. Provides a comparison of the physical characteristics of oxygen storage and transport proteins. Reviews essentials for preparation of the materials. (ML)

Describes the nine modules of the SAVI/SELPH program, a hands-on, multisensory science program developed for grade 4-7 visually impaired, orthopedically disabled, learning disabled, deaf, and multihandicapped students. Modules consist of measurement, structures of life, scientific reasoning, communication, magnetism and electricity, mixtures and…

Presents experiments using wild birds as predators and pastry as prey and colored stones as background to demonstrate natural selection. Describes the exercise as an exercise in simulating natural selection. (Author/CW)

Outlines a laboratory exercise that makes use of Beer's Law plots of cysteine constructed at several pH values over a broad range of wavelengths to estimate the tautomeric ratio (R) of two singly charged ionic forms, calculate the microscopic constants, and construct ultraviolet spectra for both light absorbing species. (CW)

Discusses the possibilities of toxins present in medicinal herbs. Describes an experiment in which toxic constituents can be selectively detected by thin-layer chromatography and NMR spectroscopy. (TW)

Discusses the uses of thermistors in teaching electronics and semiconductors. Describes how to experimentally measure and graph the characteristics of a thermistor. Suggests one possible approach to understand the shapes of the characteristics. (CW)

Explains the use of an accelerometer in investigations confirming Newton's second law. Provides diagrams and descriptions of the apparatus. (ML)

Discusses the velocity of an orbiting satellite. Knowledge of the kinematics of falling objects is the only prerequisite for understanding the concepts considered. (DH)

Describes a comparison of scale of laboratory with respect to time efficiency. Compared full scale and one-tenth scale Grignard reactions with full scale averaging 330 minutes to completion and scaled-down averaging 204. Savings are seen in air pollution, toxicity, solvent cost, and time. (JM)

Describes use of a Fresnel biprism to demonstrate double-slit interference with polarized light. Discusses polarization and phase properties of a randomly polarized gas. (JM)

While students are able to cope with the slide-wire Wheatstone bridge, the slide-wire potentiometer has had a long history of confusing and frustrating elementary physics students. Therefore, a new approach for teaching and using the potentiometer has been developed. This approach is described. (JN)

Investigated the role of "a priori" ideas in planning experiments and data processing leading to inferences. Thirty-one students (ages 11-13) observed a "combustion/candle in a closed container" experiment and were asked to interpret sets of measurements. Findings, among others, show that children preferentially experiment on…

Provides a detailed description for the construction of equipment needed to investigate acid/base equilibria through the measurement of pH and potentiometric titrations. Suggested experiments and calibration techniques are explained. This information helps to solve the problems of inadequate, expensive equipment required for A-level chemistry…

A hair dryer, plastic funnel, and microscope slide can be used for predicting pollen counts on a day-to-day basis. Materials, methods for assembly, collection technique, meteorological influences, and daily patterns are discussed. Data collected using the apparatus suggest that airborne grass products other than pollen also affect hay fever…