In a lever with a longer input arm, what happens to the mechanical advantage?

• A. It decreases the mechanical advantage.
• B. It has no effect on mechanical advantage.
• C. It increases the mechanical advantage.
• D. It reverses the lever direction.

Answer: (C)

Longer input arm increases the mechanical advantage because the lever multiplies force by the ratio of arm lengths. The mechanical advantage equals the input-arm length divided by the output-arm length. If you lengthen the input arm while leaving the fulcrum and load arm the same, that ratio grows, so you get a larger output force for the same effort: F_out = F_in × (L_in / L_out). In practical terms, you can lift a heavier load or use less input force to lift the same load. This change does not keep MA the same, nor does it reverse the direction of motion—the direction is about how you apply the force, while the advantage is about how much force is produced for a given effort.