Graduate Student Difficulties on Electrostatics Topics -- Conductors and Insulators

Abstract

A lack of conceptual understanding of electrostatics principles, especially in the context of conductors and insulators, has been observed among a large number of introductory physics students as well as upper-level physics students. This work aims to explore graduate students’ misconceptions on these topics, particularly on how charges are distributed on conductors and insulators in various scenarios. Four first-year physics graduate students were selected to participate in think aloud interviews, where they were given a set of questions related to basic concepts of conductors and insulators, and asked to explain their thought processes as detailed as possible. The result of the four interviews are categorized by the test questions, which discusses the misconceptions that were demonstrated throughout the interviews, along with the interviewees’ reasoning behind these misconceptions. Despite that the interviewees have taken the introductory and advanced electricity and magnetism courses, a number of misconceptions still prevail in their conceptual understanding related to conductors and insulators. One possible explanation is the discontinuity between their knowledge of mathematical formulation and physical understanding of the concept, thus it is recommended that instructors should enforce students to review the advanced theory in the context of physical situations.