Levers - Levers allow for mechanical advantage to be applied to an object through the use of a lever arm and a fulcrum. The fulcrum can be any object used as a fixed point to apply the lever. The mechanical advantage given by a lever is equal to the length of the effort arm divided by the length of the resistance arm. In other words, the force applied is multiplied by the ratio of the resistance arm to the effort arm. Examples of levers include pry bars, seesaws, and pliers. These tools allow a great deal of force to be applied with a modest amount of effort.