Constructing naive theories of motion on the fly

Abstract

People often make erroneous predictions about the trajectories of moving objects. McCloskey (1983a, 1983b) and others have suggested that many of these errors stem from well-developed, but naive, theories of motion. The studies presented here examine the role of naive impetus theory in people's judgments of motion. Subjects with and without formal physics experience were asked to draw or select from alternatives the trajectories of moving objects that were presented in various manners. Results from two experiments indicate that both trajectory judgments and explanations were affected by specific response and display features of the problem. In addition, these data provide little evidence that naive impetus theory plays a significant role in subjects' performance; instead, they suggest that motion judgments and explanations are constructed on the fly from contextual cues and knowledge that is not necessarily naive.

The impetus theory in judgments about object motion: A new perspective

“…Several other studies have reported similar findings (Osborne & Freyberg, 1985;Piaget, 1974;Viennot, 1979). Whether there exists a single, coherent theory of acquired force or just a set of loosely consistent, locally applied ideas can be questioned (Cooke & Breedin, 1994;diSessa, Gillespie & Esterly, 2004;Ranney, 1994), but the basic notion that objects that have been made to move acquire a force that perpetuates their motion is certainly widespread.…”

“…Students asked to draw on diagrams the forces acting in various situations tend to draw a force in the direction of the object's motion (Clement, 1982); this was found for a pendulum-where participants drew a force on the bob in the direction of its motion-for an object sliding down a track, for an object in orbit, and for a tossed coin on its way up. Cooke and Breedin (1994) found evidence for acquiredforce beliefs in almost all participants in a questionnaire study. Ioannides and Vosniadou (2002) found evidence for four core interpretations of "force" in explicit judgments by children.…”

The Implications of Research on Expertise for Curriculum and Pedagogy

“…For example, expert physicists provided predictions of object trajectories accompanied by written explanations of the means by which they reached their conclusions. However, when researchers used the explanations in an attempt to replicate the physicists' predictions, their results differed significantly from the predictions of the experts in the study (Cooke & Breedin, 1994).…”

“…However, research indicates that such self-reports often are incomplete or inaccurate (e.g., Chao & Salvendy, 1994;Cooke & Breedin, 1994). This article evaluates research on experts' cognition, the accuracy of experts' self-reports, and the efficacy of instruction based on experts' self-reports.…”

Trust in online information

“…Similarly, Cooke and Breedin (1994) found dissociations between individuals' written explanations for physics trajectory problems and their predictions of those trajectories.…”