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How does a lever use a fulcrum to lift a load?

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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.

A lever is a simple machine that amplifies physical force by pivoting on a support point called a fulcrum.12

The device functions by using the fulcrum to create a mechanical advantage. When you apply force to one end of the lever (the effort arm), the lever turns freely on the fulcrum, which acts as a hinge or pivot point. This movement allows you to exert a force on a load at the other end (the resistance arm) that is significantly greater than the force you applied yourself.12

The degree of amplification depends on the ratio of the lengths of the two arms: if the distance from the effort to the fulcrum is longer than the distance from the load to the fulcrum, the force exerted on the load is multiplied accordingly. By adjusting these distances, a lever enables a user to lift heavy objects that would otherwise be impossible to move by hand.1