Abstract ▼ AI-Helper

Using a simple experimental apparatus composed of four coils, a current sensor, an interface and a permanent magnet, we demonstrated ‘mechanical energy conservation law’ when a magnet is in free fall motion. When a magnet is in free fall motion passing through the center of coils, an induced current...

Using a simple experimental apparatus composed of four coils, a current sensor, an interface and a permanent magnet, we demonstrated ‘mechanical energy conservation law’ when a magnet is in free fall motion. When a magnet is in free fall motion passing through the center of coils, an induced current is generated by Faraday’s law of electromagnetic induction. We took wave-form data for induced currents by a data logger and measured the time intervals when it takes for the magnet to pass through the center of each coil. From wave-form data, we obtained the velocity of the magnet at coil positions and demonstrated mechanical energy conservation law. In addition, we confirmed the acceleration of gravity in Daegu province. We introduced a new experimental apparatus to show that mechanical energy conservation law is validated when we can ignore the effect of non-conservative force such as the drag force. This study will help students understand free fall motion and mechanical energy conservation and inspire students’ interest concerning the science concepts by conducting a mechanical experiment, based on electromagnetism.