In a lever, how is the mechanical advantage achieved?

The mechanical advantage in a lever is achieved primarily by using a longer lever arm. A lever consists of a rigid bar that pivots around a point called the fulcrum. When the lever arm is longer, the force applied to one end of the lever has a greater distance to carry out its work on the other end, where the load is attached. This allows a smaller input force to lift a greater load, making the lever more efficient in moving heavy objects with less effort.

When the lever arm is extended, the distance over which the input force is applied increases, which in turn increases the torque (the rotational force) applied to lift the load. This principle is captured in the lever's mechanical advantage formula, which states that the mechanical advantage is proportional to the lengths of the lever arms on either side of the fulcrum. Therefore, a longer lever arm leads to a greater mechanical advantage, enabling easier movement of larger weights with lesser force.