Advanced Undergraduate and Early Graduate Physics Students' Misconception about Solar Wind Flow: Evidence of Students' Difficulties in Distinguishing Paradigms

Anecdotal evidence has suggested that advanced undergraduate students confuse the spiral structure of the interplanetary magnetic field with the flow of the solar wind. Though it is a small study, this paper documents this misconception and begins to investigate the underlying issues behind it. We present evidence that the traditional presentation of this concept can lead to this misconception and that it persists into graduate school. Two consistent models of plasmas that apply under different circumstances are presented during the course. Evidence suggests that students attempt to apply the models to inappropriate circumstances, which leads to a misconception. There is also evidence that a fundamental mechanics misconception contributes to students' difficulties. Finally, we argue that many of the broad conclusions of the research done at the introductory undergraduate level are applicable to upper division and graduate students. In particular, we conclude that direct instruction at this level through lecture-demonstration can leave students with misconceptions and even unintentionally reinforce those misconceptions. (Contains 2 tables and 3 figures.)