A lever with a longer effort arm relative to the load arm provides which effect?

• A. Increased mechanical advantage; less force required
• B. Higher load speed
• C. More friction in the pivot
• D. No change in effort

Answer: (A)

A lever works by trading force for distance through the lengths of its arms. The input torque is the product of the effort force and the effort-arm length, while the resisting torque from the load is the load force times the load-arm length. At balance, F_in × L_e = F_out × L_l, so F_in = F_out × (L_l / L_e). When the effort arm is longer than the load arm, L_e increases relative to L_l, which makes F_in smaller for the same load. That is an increased mechanical advantage, meaning you can lift the same load with less input force.

Because the two arms rotate together, moving the effort arm farther from the pivot means the effort end travels a greater distance than the load end for each swing. So the load does not move faster; in fact, it moves a smaller distance for the same movement of the effort. The other options don’t capture this trade-off between force and distance or relate to friction or unchanged effort.