Applications of Friction in Machines

 Applications of Friction in Machines

We investigate the action of friction in various machine applications. Because the conditions in these applications are normally either limiting static or kinetic friction, 

Wedges

 A wedge is one of the simplest and most useful machines. A wedge is used to produce small adjustments in the position of a body or to apply large forces. Wedges largely depend on friction to function. When sliding of a wedge is impending, the resultant force on each sliding surface of the wedge will be inclined from the normal to the surface by an amount equal to the friction angle. The component of the resultant along the surface is the friction force, which is always in the direction to oppose the motion of the wedge relative to the mating surfaces. 

Screw friction

A screwjack is a device used for lifting or lowering heavy loads by applying comparatively smaller efforts at the end of the lever. The thread of a screw jack may be considered as an inclined plane wound round a cylinder and the principles used in solving problems on inclined plane can be applied to solve problems involving screw friction