Students' Conceptions about the Vector Characteristics of Three Physics Concepts.

This article reports on a study of grade ten students' understanding, prior to formal instruction, of three vector concepts: position, displacement, and velocity. Three aspects of the study are discussed and reported. The first aspect is the conceptual analysis of the subject matter which was used to devise appropriate interview questions; the second aspect is the rule assessment methodology which was used in the compression of the interview data, and the third aspect is the substantive results obtained from interviews with the participating students. The conceptual analysis yielded ten “implicit vector characteristics” around which interviews were constructed. From these interviews a number of inferred rules were developed using a technique similar to that reported by Siegler.1 The rules so derived suggest that while a majority of respondents appeared to be using rules similar to the physicists' model for a few vector characteristics, for most characteristics they used rules which are only a partial description of the phenomena from a physicist's point of view. But these rules are only tentative descriptions of students' frameworks and need to be tested in subsequent studies to examine both their validity and generality in other contexts involving these vector concepts.