Development and Evaluation of a Teaching Material to Visualize Combined Magnetic Fields

By making a survey of physics textbooks for the unit "Magnetic force on the current", and a questionnaire for undergraduate students, we found that some students depend on rote learning of physics rules, e.g. the Fleming's left-hand rule, to understand the magnetic force on the current. We proposed an understanding of the force based on Maxwell stress tensor, which represents a nature of magnetic field, by using our teaching material to visualize combined magnetic fields. The material is designed to get a real feeling on the magnetic force on the current. We also conducted a trial class for undergraduate students and got positive reactions for our material