Describes an apparatus and procedure for conducting an undergraduate laboratory experiment to quantitatively study the Hall effect in a plasma. Includes background information on the Hall effect and rationale for conducting the experiment. (JN)

Investigated is the period of a simple pendulum. The cases of the rigid rod and fexible cord are reviewed. By applying a variational principle it is proven that the first order correction to the period is the same for both the cord and the rod. (GA)

Describes simple modifications that will permit external triggering of certain electronic timers, thus allowing their use in experiments which require greater precision than was possible with inexpensive apparatus. (GA)

Describes a kinetic and mechanistic investigation of ascorbic acid by a substitution-inert complex in acidic medium suitable for the undergraduate level. Discusses obtaining the second order rate constant for the rate determining step at a given temperature and comparison with the value predicted on the basis of the Marcus cross-relation. (CW)

Discusses simulation program to aid in the design of enzyme kinetic experimentation (includes sample runs). Concentration versus time profiles of any subset or all nine states of reactions can be displayed with/without simulated instrumental noise, allowing the user to estimate the practicality of any proposed experiment given known instrument…

Describes an exercise involving the use of kinematics to decide if one should stop or try and get through an intersection when the traffic light turns yellow. Gives students' experience in recording data, doing simple calculations and connecting classroom studies to real world experiences. (Author/SK)

Discusses the principles of magnetic levitation presented in the physics classroom and applied to transportation systems. Topics discussed include three classroom demonstrations to illustrate magnetic levitation, the concept of eddy currents, lift and drag forces on a moving magnet, magnetic levitation vehicles, levitation with permanent magnets…

Explains that the result of collision experiments with a linear arrangement of several identical elastic balls cannot be predicted solely from the conservation laws and energy and momentum. Indicates that the system of balls must be capable of dispersion-free energy propagation. (Author/JN)

Discusses the mechanism and the change of pH during the reaction. Notes that a dramatic rise in pH occurs when the reaction nears completion. Evaluates theories by other authors. (MVL)

Contains articles on digestive enzymes in grasshoppers; bird and badger observation; reactions between hydrochloric acid and sodium carbonate solutions; observing the migration of ions; pupil's heating skills (Bunsen burners); photolysis experimentation; capillary kinetics; experience with trireme; connection circuits; special relativity; a…

Presents an experimental example illustrating the most common methods for the determination of kinetic parameters. Discusses the different theories and equations to be applied and the mechanism derived from the kinetic results. (CW)

Examines the influence of enzyme and substrate concentrations, pH, temperature, and inhibitors on catalytic activity. Follows the influence of different phosphate concentrations in the growth medium on enzyme activity. Studies regulation of enzyme synthesis by repression. Includes methodology for six experiments. (MVL)

Shows how video recordings of the Brownian motion of tiny particles may be made. Describes a classroom demonstration and cites a reported experiment designed to show the random nature of Brownian motion. Suggests a student experiment to discover the distance a tiny particle travels as a function of time. (MVL)

Follows the increase of the pH in a solution of vinegar during neutralization with commercial antacid tablets. Provided are background information, equipment details, procedures, and details of the data analysis. (MVL)

Suggests an apparatus to improve the measurement of the mechanical equivalent of heat. Describes the materials needed to construct the apparatus; the methodology of an experiment to measure the heat gained by lead shot falling through a distance of 100 meters; and the calculations made to register that gain. (MDH)