The article describes an experiment involving a solid ball resting in a smooth sheet of paper. Topics discussed include the behavior of the ball being independent on the acceleration of the paper as well several different paper removal speeds being investigated experimentally. Also mentioned are calculations involving ball rolling without slipping and ball rolling with slipping.
The article presenst a method for measuring the refractive index of liquids that can be used as a class experiment or teacher demonstration. It mentions that an open rectangular container with thin transparent walls, an opaque strips 3-4 cm wide, and a sheet of paper are among the materials needed. It states that adjustment of the strength of the source, the distance of the source from the opaque strip, and the width of the container will lead in optimally sharp shadows.