What is the formula for calculating mechanical advantage of a lever?

The mechanical advantage (MA) of a lever is defined as the ratio of the length of the effort arm to the length of the load arm. This relationship illustrates how much the lever amplifies the effort applied to lift a load.

When the effort arm—where the force is applied—is longer than the load arm—the distance from the pivot to the load—the mechanical advantage increases. This means that you can lift a heavier load with less effort, which is a fundamental advantage of using levers. The formula captures this relationship as:

MA = Effort arm length / Load arm length

This enables users to understand how well the lever system converts applied energy into work done on a load, which is the essence of leveraging mechanical tools. In practical applications, such as moving heavy objects or gaining a better force output with less input, this understanding is crucial.

In contrast, the other formulas listed do not represent mechanical advantage in the context of levers as accurately. For example, they may relate to different types of mechanical systems or forces involved but do not reflect the basic principle underlying the mechanics of levers specifically.