Frictional Electrification of Belts of Insulating Materials. II. Relation between Charge Density and Work Done Against Friction

For large values of work done against friction, the charge density on an insulating belt slipping on a metal roller exponentially approaches a limiting value. This limiting value increases as the pressure between the belt and roller is increased. A triboelectric series can be formed for the two belt materials and the two roller materials used in these experiments. The positions of the rollers in this series are qualitatively related to their contact potential differences.