Intuitive physics of free fall: an information integration approach to the mass-speed belief
Michele Vicovaro · Redalyc (Universidad Autónoma del Estado de México) · 2014
In this study, the intuitive physics of free fall was explored using Information Integration Theory and Functional Measurement. The participants had to rate the speed of objects differing in mass and height of release at the end of an imagined free fall. According to physics, falling speed increases with height of release but it is substantially independent of mass. The results reveal that the participants hold a strong mass-speed belief, i.e., they believe that heavier objects fall faster than lighter ones. Mass and height of release are integrated according to a multiplicative rule. The results are interpreted as providing support to the hypothesis of the perceptual-motor origin of the mass-speed belief. Implications of the results for physics education are discussed. History books tell us that when Galileo Galilei (1564 - 1642) was still a young mathematics teacher, he conducted a brilliant demonstration for his students and colleagues. He dropped pairs of objects of the same material but different masses from the top of the famous leaning tower of Pisa, and showed that they fell with the same acceleration touching the ground simultaneously (Drake, 1978) 1 . Actually, this famous account of Galileo’s demonstration is probably inaccurate because on Earth, when objects are dropped from the top of buildings or towers (as it was the case of Galileo’s demonstration), heavier objects fall slightly faster than lighter ones because