Teaching the moment of inertia by measuring the angular speed with a smartphone’s sensors

Abstract

This paper demonstrates the use of the sensors of a smartphone in recording experimental data for studying the moment of inertia of a compound pendulum. The smartphone was attached to the beam to record at various points the angular position and angular speed of a compound pendulum. We altered the position of the smartphone along the beam resulting in the change of the system’s moment of inertia. The experimental result agreed with the theoretical calculation. This experiment will stimulate students to conduct such an experiment themselves and helps students understand the relationship between angular speed and its moment of inertia.

Smartphones as Smart Tools for Science and Engineering Laboratory: A Review

“…A proximity sensor was also proposed to precisely measure the oscillation period of a simple pendulum [62]. Using a smartphone, the oscillation of a physical pendulum was analyzed in the case of large angles [63], and the moment of inertia of a physical pendulum could also be obtained [64]. A smartphone accelerometer was also used to verify the energy conservation in the pendulum oscillation [65].…”