For a small coefficient of friction, the angle f is small, and the sine and tangent may be interchanged with only small error. Since, , a good approximation to the torque is
BELT AND PULLEY
The figure at the left hand side below shows a belt passing over a pulley. The right hand side figure shows the forces acting on a differential element of the belt.
Application of Friction |
collinear with it. Thus, R will be tangent to a small circle of radius r called the friction circle. The angle between R and its normal component N is the friction angle f. Equating the sum of the moments about contact points to zero gives |