The mass of a flywheel is concentrated on the rim primarily to maximize its moment of inertia. A flywheel is a rotating mechanical device that stores energy and helps maintain a constant speed in machinery. By placing the mass at the rim, we increase the distance from the axis of rotation, which enhances the flywheel’s ability to resist changes in angular velocity.
When the mass is distributed further away from the center, the moment of inertia increases significantly, leading to greater stability and energy storage capability. This design allows the flywheel to effectively smooth out fluctuations in rotational speed, providing a steady output of energy. Additionally, a flywheel with its mass on the rim can spin faster and store more kinetic energy, making it more efficient in its function.