University physics students' use of models in explanations of phenomena involving interaction between metals and electromagnetic radiation

Abstract

We examine third year university physics students' use of models when explaining familiar phenomena involving interaction between metals and electromagnetic radiation. A range of scientific models are available to explain these phenomena. However, explanations of these phenomena tend not to be used as exemplars of scientific models within undergraduate physics education. The student sample is drawn from six universities in UK and Sweden. These students have difficulties in providing appropriate explanations for the phenomena. Many students draw upon the Bohr model of isolated atoms when explaining light emission of metals. The students tend not to recognize that atoms in metals interact to give an electronic structure very different from that of the isolated atom. Few students use a single model consistently in their explanations of these related phenomena. Rather, students' use of models is sensitive to the context in which each phenomenon is presented to them.