Classes of Levers

In the seesaw, the effort is applied on one side of the pivot to lift a load on the other side. This arrangement is typical of one kind of lever, called the first-class lever. In other classes of levers, the effort, pivot,and load life in different relative positions. In a second-class lever, the picot is located at one end. The effort is applied at the other end to lift a load in the middle. The wheelbarrow is a second -class lever. It has the pivot at one end and the load in the middle. A bottle-open-er is another second-class lever. Your forearm is an example of a third kind of lever, the third-class lever. It has the pivot at one end- the elbow. The load is held in the hand at the other end. The effort,which is supplied by the muscle in the arm, acts between.