In a lever system, increasing the length of the effort arm increases

In a lever system, increasing the length of the effort arm increases

• A. the mechanical advantage
• B. the load on the lever
• C. the friction in the pivot
• D. the weight of the lever

Answer: (A)

When you use a lever, what matters is torque: effort torque equals effort force times the distance from the fulcrum (the effort arm). Mechanical advantage is the ratio of that effort arm length to the load arm length. So, making the effort arm longer increases the torque you generate for the same effort, which raises the mechanical advantage. With a higher mechanical advantage, you can lift the same load using less effort. The load itself doesn’t get bigger just because you lengthened the effort arm, and the pivot friction or the lever’s own weight aren’t the factors being controlled by changing the arm length in the ideal model.

When you use a lever, what matters is torque: effort torque equals effort force times the distance from the fulcrum (the effort arm). Mechanical advantage is the ratio of that effort arm length to the load arm length. So, making the effort arm longer increases the torque you generate for the same effort, which raises the mechanical advantage. With a higher mechanical advantage, you can lift the same load using less effort. The load itself doesn’t get bigger just because you lengthened the effort arm, and the pivot friction or the lever’s own weight aren’t the factors being controlled by changing the arm length in the ideal model.