Device Used In The Experiment (IMAGE) CNRS Caption The participants could modify the position of 4 weights attached to the wheel's spokes, in an attempt to increase its speed along the sloping rail. Two factors have an impact on this speed: the distribution of the mass around the wheel's axis, or moment of inertia (the closer the weights to the axis, the greater its speed), and the position of the wheel's centre of mass (the higher it is, the greater the acceleration). Credit Maxime Derex Usage Restrictions May only be used to report on this research, with appropriate credit and caption. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.