Provides an analysis of the forces causing the erratic motion of a knuckleball. Reveals the manner the ball should be thrown to provide maximum deflection. (Author/CP)

Presents a simple means for extending the Bohr model to include relativistic corrections using a derivation similar to that for the non-relativistic case, except that the relativistic expressions for mass and kinetic energy are employed. (Author/GS)

An analysis of the minimum stopping distance problem is presented taking into account the effect of weight transfer on nonskidding vehicles and front- or rear-wheels-skidding vehicles. Expressions for the minimum stopping distances are given in terms of vehicle geometry and the coefficients of friction. (Author/BB)

Discusses the criteria and procedure for optimizing the performance of Archibald rubber-band heat engines by using the appropriate choice of dimensions, minimizing frictional torque, maximizing torque and balancing the rubber band system. (GA)

Obtains the orbits with reference to the center of mass of two bodies under mutual universe square law interaction by use of the eccentricity vector which is equivalent to the Lenz vector within a numerical factor. (Author/SL)

Demonstrates that investigating coriolis effects in a fixed frame leads to a clearer understanding of the physical nature of the phenomenon. (SL)

Examines the motion of a particle in a noncentral potential using the action-angle formalism. (SL)

The lack of parallelism between the force and acceleration vectors has several apparently paradoxical consequences that have been recently examined. This article uses a different and more general mode of analysis than previous authors to derive quite general, rather than particular, results. (Author/SK)

Describes a technique for imparting essentially the same speed, in opposite directions, to two gliders to demonstrate that total momentum of equal masses traveling at the same speed in opposite directions is zero. Also describes a technique using a compression spring and beeswax for momentarily holding two gliders together prior to starting them…

A discussion of linear collisions between two or three objects is related to a junior-level course in analytical mechanics. The theoretical discussion uses a geometrical approach that treats elastic and inelastic collisions from a unified point of view. Experiments with a linear air track are described. (Author/TS)