A system displaying equipotential lines from electrodes in real time

Abstract

Electric field is a fundamental quantity that is studied in the secondary and university levels. For the study, an experiment of finding equipotential lines from the charged electrodes is conducted. For the general experiment, the electric potentials are measured at various positions around the electrodes using a voltmeter. The measured data are then manually plotted to a graph to show the equipotential line. This experimental method is time-consuming (more than 1 hour in experiment). It is complicated to study of multiple electrodes using this experiment. Therefore, this research developed an experimental set that can display equipotential lines from various electrodes in real time. The developed experimental set uses a microcontroller (Arduino MEGA) to control a stepper motor to determine measuring positions of electric potential and measure electric potential at various positions around the electrodes (point of charge), automatically. The measured electric potentials and positions were plotted in contour graph to display patterns of the equipotential lines via a computer. The experimental set was tested using 2, 3 and 4 electrodes. The results showed that the developed system was able to display the equipotential lines of the electrodes within 2 minutes. The patterns of the equipotential lines were consistent with the equipotential lines generated from the theory. The correlations of the electric potential values from the experiments and the theoretical simulations for the systems of 2, 3 and 4 electrodes were 0.9452, 0.8691 and 0.9193, respectively. These results demonstrate that the presented experimental set can be used to display the equipotential lines from the electrodes effectively.