The stepped shaft is secured to a main shaft, which itself is secured within a bracket. The bracket can be bench or wall mounted.
Wrapped around the circumference of each step of the shaft is cord. At the ends of each cord is a single adjustable bob. The adjustment of the bobs can be made to ensure that the starting positions of each bob is the same even though the steps are different diameters. Alternatively the starting position of each bob can be made different.
Shaft is rotated by a pin which can also be used to lock shaft. The angular movement of the shaft and the corresponding linear movement of the weights can be compared.
A comprehensive instruction manual for lecturer and student, giving full details on apparatus assembly and operation as well as example results. All necessary assembly and operational tools are provided.