fulcrum

Definition

A fulcrum is the point on which a lever pivots. It is the point where the force is applied to the lever. The fulcrum is important because it determines the mechanical advantage of the lever.

Mechanical advantage is the ratio of the force applied to the lever to the force that is exerted on the load. The greater the mechanical advantage, the less force is needed to lift a load.

The mechanical advantage of a lever is determined by the ratio of the distance between the fulcrum and the load to the distance between the fulcrum and the point where the force is applied. The greater the distance between the fulcrum and the load, the greater the mechanical advantage.

For example, if the distance between the fulcrum and the load is twice as long as the distance between the fulcrum and the point where the force is applied, then the mechanical advantage of the lever is 2. This means that you only need to apply half as much force to lift the load as you would if the fulcrum were closer to the load.

How can the word be used?

The fulcrum is the most important part of a lever.

Different forms of the word

Noun: fulcrum, fulcra.

Adjective: fulcral.

Etymology

The word "fulcrum" comes from the Latin word fulcrum, which means "support" or "prop". The Latin word fulcrum is derived from the verb fulcire, which means "to prop up" or "to support".

Question

Provide an example of a fulcrum in use.

AQA Science Exam Question and Answer

Question:

Explain the concept of a fulcrum in simple machines and how it influences mechanical advantage.

Answer:

In the realm of simple machines, a fulcrum is a pivotal point around which a lever rotates or moves. It serves as the central support, allowing the lever to exert force and facilitate work. The mechanical advantage of a lever, which determines its efficiency, depends on the placement of the fulcrum relative to the points of effort and load. When the fulcrum is closer to the load (resistance) and farther from the effort (applied force), the lever provides a mechanical advantage, requiring less effort to lift or move heavy loads. Conversely, if the fulcrum is closer to the effort and farther from the load, the mechanical advantage diminishes, demanding more effort to move the load. The fulcrum's position in a lever system significantly influences the ease and efficiency of performing tasks, making it a crucial aspect of simple machine design.