engleski

Analyzing students' reasoning in electromagnetism

Research shows that students’ understanding of concepts from electricity and magnetism is often inadequate after standard instruction based on lectures. Students are often not enough engaged in activities that would allow them to construct deeper understanding of physics concepts. This approach may lead to deficiencies in students’ knowledge structure. Many concepts are known to be difficult for students, and the concept of electromagnetic induction is considered one of the most difficult among them. The objective of this research was to investigate students’ understanding and conceptual models of several electromagnetic phenomena, formed after standard lecture – based instruction in Croatian high schools. The investigated phenomena included magnetic fields around a steady current-carrying wire and inside coils, force on a current-carrying wire in a uniform magnetic field, electromagnetic induction and Lenz's law. For the purpose of this research, a small number of Croatian high school students, aged 16-17, were interviewed after they had completed a course on electromagnetism. After having been shown a demonstrational experiment, students were asked to describe what they had observed and whether they could explain their observation. Each student was asked to think aloud, so that their reasoning could be analysed. Students were not corrected if they had arrived at the wrong conclusions. After they had formed their conclusion and stated that they had nothing to add, the interviewer gave them clues in form of additional experiments, as an attempt to create situations for students to test and revise their own ideas. The interviews were recorded with a video camera and transcribed for later analysis. Content analyses of the reasoning models constructed by these high school students showed a gap between the expected and the observed lines of reasoning. Students seem to have created their own incorrect models of electromagnetic phenomena, even though they had just successfully completed a course on it. They had difficulties in explaining how a magnetic needle works, or why it changes direction when put under a current-carrying wire, and needed to form their own new model of the phenomenon. They were able to regulate, re-evaluate and upgrade their model in a way an expert would do when given clues and asked questions. This research suggests that standard instruction on electromagnetism may be insufficient for students to form a correct model of the phenomena and to achieve the right conceptual understanding. Teachers should be aware of students’ incorrect reasoning patterns and try to correct them during teaching.

electromagnetism; interview; student reasoning; reasoning model; content analysis

nije evidentirano