Wedge A wedge is two inclined planes attached to each other. The wedge makes work easier by splitting something when force is applied. Often, wedges are used in conjunction with levers. A screw concentrates the force applied on an object to a smaller area. It pushes a concentrated amount of force away from the user.
Less surface is exposed to the stationary object.
Pulley A pulley makes work easier by changing direction of the force applied. When force is exerted downward, the object moves up or across.