The vertical pendulum

A paradigmatic physical system is the physical pendulum is experimentally studied using the acceleration and rotation. We used smart phone sensors to analyze a vertical pendulum, which was in fact a bicycle wheel. The sensors used in our experiment were the smartphone’s inbuilt gyroscope and accelerometer. Gyroscope is used to measure angular velocity of the wheel while the accelerometer is used to measure the linear acceleration of wheel. A smartphone is fixed to the outside of a bicycle wheel whose axis is kept horizontal and fixed. The compound system, wheel plus smartphone, defines a physical pendulum which can rotate, giving full turns in one direction, or oscillate about its equilibrium position (performing either small or large oscillations). Measurements of the radial and tangential acceleration and the angular velocity obtained with smartphone sensors allows a deep insight into the dynamics of the system.