It is hard to observe relativistic effects in everyday life. However, table experiments using a mechanical transmission line for solitons may be an efficient and simple way to show effects such as Lorentz contraction in a classroom. A kink soliton is a deformation of a lattice of several dozen or more pendulums placed on a wire and connected by a…

The familiar system involving a uniform ladder sliding against a vertical wall and a horizontal floor is considered again. The floor is taken to be smooth and the wall to be possibly rough--a situation where no matter how large the static friction coefficient between the ladder and the wall, the ladder cannot lean at rest and must slide down.…

According to historical stories, the Saxons placed a bowl with a hole in its bottom in water and used the time it took the bowl to submerge to limit orations. Describes a science activity in which students find a relationship between the diameter of the hole and the time to submergence. (WRM)

Describes an experiment that extends Newton's instantaneous-impulse method of orbital analysis to a graphical method of orbit determination. Discusses the experiment's usefulness for teaching both horizontal projectile motion and instantaneous impulse. (WRM)

Describes a simple demonstration of the flow of sand through an orifice at the bottom of a sandbox. Advocates the experiment's use with dimensional analysis for students in an introductory physics course. (WRM)

Describes a procedure for the datalogging of microbial population densities. (WRM)

Describes changes in scientific research methods that have been brought about by the use of computers. Presents an example of the falling of a body in a fluid to show students how computers can be used to experiment with mathematical models and to automate experiments. Contains 11 references. (Author/WRM)