Several recent studies in which subjects solved pencil/paper problems concerning the behavior of moving objects have shown that many people have incorrect beliefs about motion. The present study considered the question of whether these naive beliefs are manifested in situations where people observe and interact with moving objects. Several findings in the problem-solving literature suggest that abstract or unrealistic tasks may fail to tap knowledge and reasoning abilities that are routinely employed in more concrete or realistic situations. Thus, most people may have accurate knowledge about the behavior of moving objects, which knowledge they employ in their everyday interactions with objects in motion. However, this knowledge may not be activated in the context of abstract, static problems, and as a result people attempting to solve such problems may resort to naive beliefs. Three experiments examined this possibility in the context of one naive belief, the curvilinear impetus belief. Subjects were college students (Experiment 1: N=90; experiment 2: N=72; experiment 3: N=50). Contrary to expectations, results suggest that the curvilinear impetus belief is employed not only on paper/pencil problems, but also in situations where people observe and interact with moving objects. Implications of these findings are discussed. (Author/JN)