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How does the position of a fulcrum change a lever's mechanical advantage?

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A diagram displays six types of simple machines with labeled illustrations: inclined plane, wedge, screw, lever, wheel and axle, and pulley, each shown with real-world examples like ramps, axes, screws, seesaws, door handles, and pulleys lifting objects. — simple machine Six simple machines for transforming energy into work.

The mechanical advantage of a lever—a type of simple machine—is determined by the position of the fulcrum relative to the points where the effort and load are applied.

The mechanical advantage is defined as the ratio of the output force (the load) to the input force (the effort). In a lever, this ratio is directly proportional to the lengths of the lever arms extending from the fulcrum. If the distance from the effort to the fulcrum is significantly longer than the distance from the load to the fulcrum, the lever amplifies the input force.12

For example, if the distance from the effort to the fulcrum is five times the distance from the load to the fulcrum, the output force will be five times the input force. By adjusting the fulcrum's position, you change the ratio of these distances, thereby modifying the force-amplifying effectiveness of the machine. Essentially, what is gained in force through this positioning is lost in the distance the effort must move compared to the load.231