Explains and illustrates strange events which occur when two pendulums interact through a variety of interconnections. Phenomena addressed include: pendulums coupled by a spring, rod, or string; vertical and rotational oscillations, and synchronous and mirror-image swinging. A resonant-spring pendulum and a Wilberforce pendulum are also discussed.…

Describes a rapid, visual demonstration of protein separation by gel filtration chromatography. The procedure separates two highly colored proteins of different molecular weights on a Sephadex G-75 in 45 minutes. This time includes packing the column as well. Background information, reagents needed, procedures used, and results obtained are…

Describes a physical/organic chemistry experiment on conductance behavior of hydrogen-bonded species of six salts of easily accessible, nitrogen-containing bases and halogenoacetic acids. The bases and acids used are much cheaper and have comparatively less unpleasant odors than the pyrim puridines and trifluoroacetic acid used in previously…

Describes electricity experiments which can be used for such purposes as determining the magnetic field of a magnet, making an electromagnet, and showing the repulsion of like poles of a magnet. Includes list of materials needed, procedures used, and instructional strategies. (JN)

Background information, procedures used, and typical results obtained are provided for an experiment involving the separation of chlorophyll a and chlorophyll b from their diastereomers. Reasons why the experiment can be easily integrated into most laboratory curricula where high-performance liquid chromatography capabilities exist are given. (JN)

Provides a method for correcting the photoemission from a collector when using the photoelectric effect experiment to determine Planck's constant. The problem results from a negative current through the cell and makes the measurement of the cutoff potential difficult. (DH)

Presents a field formula for calculating speed and flight efficiency of soaring birds. By estimating the size of the bank angle and timing the complete circle, the observer can determine the speed and circling radius on a chart provided. Lift coefficients and flight characteristics of several birds are also discussed. (DH)

Background information, materials needed, laboratory procedures, and typical results are provided for five high performance liquid chromatography experiments (three isocratic and two step gradient separations). Suggestions for further experimentation are also provided, including quantitative determinations and separation of charged solutes. (JN)

Brief descriptions are presented of 40 demonstrations and laboratory experiments in electrodynamics, complementing the ninth grade physics text. (Author/JH)

Experimental design of packaging materials to withstand the impact of gravity by 5th grade students. (EJS)