<P> 2 . Dragging coefficient of friction μ g (\ displaystyle \ mu _ (g)) and angle α (\ displaystyle \ alpha) are satisfying the following criteria for all points of the curve </P> <P> − μ g <tan ⁡ α <+ μ g (\ displaystyle - \ mu _ (g) <\ tan \ alpha <+ \ mu _ (g)) </P> <P> 3 . Limit values of the tangential forces: </P> <P> The forces at both ends of the rope T (\ displaystyle T) and T 0 (\ displaystyle T_ (0)) are satisfying the following inequality </P>

Where does the gripping friction occur on a belt