Energy "lost" in rolling, sliding and torsion Hey everybody, I have a question concerning three states and the state of energy in them. 1. Rolling 2. Sliding 3. Torsion For example: If I have a steel cylinder with diameter d on an axis (no friction in the axis) rolling horizontally over a rubber surface, is the energy (work done), just the simple horizontal force in the axis times distance? What happens, if I block the cylinder and slide it over the surface? Third question would be just to rotate the cylinder without horizontal movement at all. Any ideas would be greatly appreciated ;-) Phil EDIT: defined the contacting surfaces. Surface cylinder = steel, 2nd Surface = rubber block.