Student difficulties with vectors in kinematic problems
E.F. Redish and G. Shama,
AAPT meeting, Denver, August, 1997.
Students in introductory physics often have difficulties with the concept of vectors. We have observed and analyzed student performance in a small class of first-semester algebra-based physics at the University of Maryland. Students were observed in tutorials and during in-lecture discussions, and their homeworks and examinations were analyzed. All of the students made errors in the meaning and use of vectors in kinematic problems. We conjecture that their difficulties result from a mental model of motion that retains the full path as the description of the motion, and that contains inappropriate rules for extracting average or overall features from this full description. We refer to this mental model as path dominated. An exam question designed to test this hypothesis was delivered to 135 students. In this problem, approximately ½ of the students made errors that may be explained as a result of path-dominated misconceptions.