Resumen de Bridging the Conceptual Gap Between Free Fall and Drag-Dominated Regimes
Elida de Obaldia, Norma Miller, Fred Wittel, George Jaimison, Kendra Wallis
Some misconceptions about physics are hard to change. For example, students continue to believe that heavier objects fall faster than light ones, even after a year of physics instruction. Physics misconceptions are persistent. Light objects do fall more slowly if their size-to-weight ratio is sufficient for drag to be appreciable. Motion through a viscous medium is an advanced topic and students are asked to hold their curiosity until they take a more advanced course. Most never will. We suggest that the idea that heavier objects fall faster (or lighter objects fall slower) is a reasonable approximation that people develop from observing the world around them. We also suggest that discussing drag qualitatively at the outset may allow students to reconcile what they learn in physics class with a concept formed in early childhood. This approach asks students to modify their concept rather than discard it. In this paper we present a simple physics lab experiment that can be performed with readily available equipment and which bridges the gap between the domains of constant velocity and constant acceleration free fall. It is motivated by a lab experiment described in Paul Robinson's laboratory manual.
