2020 Volume 61 Issue 2 Pages 277-286
Prior to the introduction of the trial lesson on principles of electric motors to a high school science class in the Philippines, the students lacked understanding of the relationship among the direction of electric current, the magnetic field, and the force induced. There were few students who understood the mechanism that motors rotated. The devised lesson plan utilized an electric swing and a coil (clip) motor as teaching materials that students could use in their experiments to promote their interest and enhance their understanding beyond textbook study. The coil motor successfully elicited the students’ interest in electromagnetic phenomenon since the coil rotates. However, this teaching material alone did not increase their degree of understanding of the scientific principle targeted in the lesson, as it is visually difficult to identify the direction of electric current that a coil creates when wound up many times. Thus, an electric motor of the electric swing type was developed for this study, and the effectiveness of this teaching material was evaluated in a trial lesson in a high school science class via inquiry-based study. The findings are as follows: 1) This lesson was useful to enhance students’ understanding of the direction of electric currents and magnetic fields. 2) This lesson was fun for the students; while not too difficult, the lesson encouraged students’ critical/analytical thinking. 3) This lesson effectively promoted understanding of the direction of physical force necessary to push the electric conductor in a magnetic field. 4) This lesson was useful to help students understand the reason that the electric motor continues to rotate.
