One may use such pulley arrangements to allow just one or two men to lift a large, heavy object such as a piano or safe. (Figure \PageIndex1) Note that the leftmost arrangement only changes the ...One may use such pulley arrangements to allow just one or two men to lift a large, heavy object such as a piano or safe. (Figure \PageIndex1) Note that the leftmost arrangement only changes the direction of the applied effort force, by allowing us to pull downward to lift the weight upward; it does not provide any mechanical advantage. (Ref. The mechanical advantage of a set of pulleys is equal to the number of strands NR holding up the resistive force:
