In this paper, we show how to construct a time marker similar to that adopted by the PSSC (Physical Science Study Committee) using an aquarium air pump and a hydrographic pen. We also show how this marker can be used either to register the motion of an object from the dots printed on a paper tape attached to the object, or to measure time intervals with the aid of electronic techniques to automatically start/stop its functioning. The suggested experiments allow students to learn the relationship between displacement, velocity, and time associated with a uniformly varied motion, as well as studying the physics related to translation and rotation dynamics.
Keywords:
Time marker; aquarium air pump; hydrographic pen; inclined plane
