What Is a Combined Pulley?
A combined pulley is a type of pulley that has and uses movable and fixed pulleys simultaneously. In this system, many pulleys can be used at the same time with less weight needed to lift an object.
As is the case with other types of pulleys, a combined pulley is used to change the direction of force so that lifting is made easier. Whereas a fixed pulley does not, movable pulleys move with the load being moved. When movable and fixed pulleys are combined to form a combined pulley, the effort needed to pull or lift a load is less than half the weight of the load.