Netherlands in “ sophistkated ” subjects : ceptions abo t traject & ies of obj

University students were asked to solve simple problems about the trajectories of falling objects. A majority of the student? revealed a variety of misconceptions about motion. However, the few basic patterns of responses produced by the subjects suggest considerable commonality in the types of naite physical ‘laws” people develop on the basis of everyday experience with the world. The ability to interact successfully with moving objects implies some sort of knowledge about motion. For example, a baseball player who is able to catch a fly ball must have abstracted from his perceptual experience some form of knowledge that enables him to position himself at the location where the ball will land. It is not obvious, however, what types of knowledge are the case that normal experience with n of coherent abstract principles that are al laws of physics: Alternatively, experion of limited, concrete information about of several ex~e~ments we have recently confrom perience the world on of at variance with Surprisi , however, the most fundamental *Tla ruch Instftlm of EduMi stion he Structure sf KacbwWge in Scienos and Mathe Grant SSO7 RR070464 3. Any opinfons, fin&~, sonc?lusfonar o recommendations expressed herein we thoac of the authors and ds not neceasariJy reflect the view of the National Science Foundation or the Nationa! Institute of Education. Reprint requeets should be wat to: Alfonso Caamazza, Department of Pswhology, The %ohns Hopkins UniversSty, Baltimon, Maryland 21218. 118 A. Caramazza, M. McCdoskey GE& B. Green physical laws. Furthermore, the naive principles are espoused not only by people with no formal instruction in physics, but also by a large proportion of those who have completed high school or college physics courses. In this report we describe an experiment concerned with people% beliefs about projecer’le motion. Fifty undergraduate students at the Johns Hopkins University served as subjects. Six subjects failed to follow instructions, and their data were not included in our analyses. Of the remaining 44 subjects, 10 had completed at least one college-level course in physics, 20 had taken high school physics, and 14 had received no formal physics instruction at the high school or college level. Each student was asked to solve 13 simple problems, of which 4 will be discussed in this report. These 4 problems, shown as problems A through D in Figure 1, required the students to trace the trajectory of a falling object. The problems were pxsented separately, one per page, as line drawings of a metal ball suspended by a string. Subjects were instructed to consider the ball and string depicted in the line drawings as moving in an arc as a pendulum. They were then asked to draw the path the ball would follow if the string were cut when the ball was at the location indicated and moving in the direction indicated in the line drawing. The results of the experiment are remarkable in what they reveal about subjects’