A movable pulley is a pulley exactly where when you go a heavy object, the drum moves with it. There is no modify in the direction of the power you need to have to implement, but the load will “come to feel” lighter than it actually is. For instance, if you are hauling a heavy hay bale up the barn’s attic, a moveable pulley will make the load truly feel a good deal lighter, even even though you are pulling in the same course.