Presents an experiment to study the acceleration of a cart moving up and down an inclined plane. Demonstrates how multitiming and the study of the movement in both directions allows the determination of the component of gravitational force along an inclined plane without any assumptions about friction. (JRH)

Describes experiments simulating the mechanics of the human elbow and back. (SL)

Describes equipment used for a magnetic force experiment that is capable of producing precise results but rugged enough to withstand handling by several hundred undergraduate students per year. (WRM)

Explains a projectile motion experiment involving a bow and arrow. Procedures to measure "muzzle" velocity, bow elastic potential energy, range, flight time, wind resistance, and masses are considered. (DH)

Uses the context of sports surfaces to discuss the qualities of a surface that will produce a shock-absorbing effect. Discusses experiments to measure the shock-absorbing properties from two theoretical perspectives. Describes necessary equipment for the experiments. (MDH)

Describes modifications to an apparatus for measuring the force of an object in circular motion. Explains how to accurately measure rotation rate with the use of a motion detector. (WRM)

Describes an inexpensive tensiometer, a balance consisting of a plastic drinking straw as the crossarm, a needle as a pivot, and wire loop counter balance to assure proper balance. The instrument permits the quantitative demonstration of interfacial tension and effects of various agents that modify it. (Author/JN)

Describes three demonstrations/activities that involve forces: (1) a canoe-like boat made from copper window screen; (2) magnetic forces with a paper clip and ceramic magnetic; and (3) an "icemobile" machine that cuts ice cubes without an obvious source of energy. (DH)

Describes: the chemical history of a pencil; a simple solar camera for measuring the sun's diameter; the experimental comparison of the thermal stability of metal carbonates; and the introduction of the concept of weight as a force to young children. A computer program listing on color mixing is also provided. (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 the rebuilding of a Project Physics fan cart on a PASCO dynamics cart chassis for achieving greatly reduced frictional forces. Suggests four experiments for the rebuilt cart: (1) acceleration on a level track, (2) initial negative velocity, (3) different masses and different forces, and (4) inclines. (MVL)

Describes a coriolis simulator which uses a carbon paper trace technique and a simple specific-heat apparatus, emphasizing instructional considerations. Also indicates that a variac and an ordinary electric drill can be used to wind coil if a lathe or coil winder are unavailable. (JN)

Describes an experimental sequence using the force probe to develop the relationship between net force and acceleration. (PR)

Describes the construction and use of a magnetic needle that is stronger than those conventionally used for experiments with electromagnetism. (WRM)

Presents an examination of the buoyancy principle which can serve as a simple but rigorous illustration of a falsification test that not only clears up a possible misconception but also points the way to a number of practical uses of buoyancy measurements that have not generally been recognized. (MVL)