抄録
We propose a teaching method which can visualize voltage drops in series circuit of resistors utilizing Joule heat. We used a thermography camera in order to measure the temperature of whole the circuit. Brightness of obtained images indicate temperatures of the observing points. Furthermore, measured temperatures were converted into voltage drops across the resistances. The proposed method is easily composed by teachers and supposed to help elementary and junior high school students to understand the content of electricity such as series circuit.