Tracking the Motion of a Simple Pendulum with Tracker

Open-source video analysis and modeling program “Tracker” is a powerful tool in physics education and classroom teaching. The application of Tracker is demonstrated in this article with a simple and well-studied problem, the simple pendulum. The motion of the pendulum is videographed using a smartphone and analysed with Tracker for different amplitudes of oscillation. The period of oscillation and phase-space trajectory of the pendulum are determined using this application and compared with results from the standard textbook theory. A first-order anharmonic coupling factor is determined from the measured frequency shift, which is found reasonable with the analytical result.