What distinguishes a first class lever?

A first-class lever is characterized by having the fulcrum positioned between the load and the effort. This arrangement allows the lever to balance force and motion effectively. In practical terms, when you apply effort on one side of the fulcrum, it allows you to move the load on the opposite side with potentially less effort, depending on the distances of the load and effort from the fulcrum.

This unique configuration means that the lever can either amplify force or increase the speed and distance of the load movement, a feature that is utilized in various applications such as seesaws and certain types of crowbars. The placement of the fulcrum is critical in determining the mechanical advantage and functionality of the lever system.