Officer Aptitude Rating (OAR) Practice Exam – Prep & Study Guide

The configuration of a third-class lever is characterized by having the effort applied between the load and the fulcrum. This means that the fulcrum is located at one end of the lever, while the load is positioned at the opposite end. The key feature of a third-class lever is that the effort is applied closer to the fulcrum than the load, which results in a mechanical advantage of greater speed and distance rather than force.

By having the effort in the middle, the lever amplifies the distance moved by the load compared to the distance moved by the effort. This is why tools like tweezers and fishing rods are considered third-class levers; they allow for a precise application of force while enabling the load to be moved a greater distance.

In contrast, configurations described in the other choices do not align with the definition of a third-class lever. For instance, if the fulcrum were in the middle, as described in option B, it would be a second-class lever, while placing the load in the middle as described in option C, would indicate a first-class lever. Thus, the positioning of the effort, fulcrum, and load is crucial to understanding the distinct types of levers.