What is the purpose of a wedge?

Answer 1

The wedge is the active twin of the inclined plane. It does useful work by moving. In contrast, the inclined plane always remains stationary. This simple machine consists of a pair of inclined planes set face-to-face, that can sustain relative sliding or rolling motion. By moving one plane relative to the other, a wedge is capable of building up enormous force in a direction perpendicular to that of the moving wedge. Force multiplication varies inversely with the size of the wedge angle; a sharp wedge ( small inclined angle ) yields a large force. With adequate friction at the interfaces, the wedge becomes a separating, holding and stopping device with countless mechanical applications.