How is the Ideal Mechanical Advantage (IMA) of a lever calculated?

The Ideal Mechanical Advantage (IMA) of a lever is defined as the ratio of the lengths of the two arms of the lever, specifically the load arm length to the effort arm length. This is because IMA describes how much a machine can multiply the input force compared to the output force, assuming no losses due to friction or other factors.

In a lever, the effort arm is the distance from where the input force is applied to the fulcrum, while the load arm is the distance from the fulcrum to the load that is being lifted. By calculating the ratio of these two lengths, you can determine how effectively the lever amplifies the effort applied. A longer effort arm compared to the load arm means that less effort is needed to lift a greater load, which is the principle behind how levers work to provide mechanical advantage.

Since the correct formula expresses this relationship accurately by taking the load arm length and dividing it by the effort arm length, it clearly shows the dependency between these two critical distances in the context of a lever's function.