Steel spheres are like those extra dice you have laying around from some old board game.
You know that you at some point are going to need them. They are useful for a wide variety of experiments including the study of potential & kinetic energy; velocity & acceleration both linear and rotational; friction and rotational inertia. There always seems to be a need in a physics experiment for a steel ball. This versatile set contains 4 shiny stainless steel spheres with one each in sizes of 1/2" 3/4" 7/8" 1" diameters with chrome finish.