A Reconsideration of the Method of Teaching Ohm’s Law

Abstract

Many teachers find it difficult to teach Ohm’s Law (Fukuyama, 2000). In this study, the difficulty of teaching Ohm’s Law, in other words, the difficulty of learning from the students’ point of view, stems from the irrationality of the “heuristic experiments” shown in the textbook. This study is a practical study to improve students’ learning of Ohm’s Law by changing the experimental method to one that employs deductive testing through hypothesis formation. The process of abduction, which is a hypothesis formation process, becomes easier by treating previous knowledge and experience logically. Of the three variables of voltage, resistance, and current, in the actual circuit, only voltage was the independent variable, while current was the dependent variable, and resistance was treated as a constant in the circuit. The concept of conductance, the inverse of resistance, was used as an intermediate concept in the learning process. These measures allow us to treat Ohm’s Law as a simple proportional expression. They make easier to understand mathematical language as a scientific proposition. For these reasons, we propose to express Ohm’s Law as I=V, instead of V=RI or R= as shown in many textbooks. It was thus clarified that these treatments are effective to make Ohm’s Law easier for junior high students to learn.