Lever Mechanical Advantage

Steps:

• Identify lever as class 1 with pivot between load (tank) and effort (farmer's force at rod end).
• Recall output force = input force × (effort arm / load arm), where effort arm is pivot to effort, load arm is pivot to load.
• Note input force constant, so increase output by maximizing effort arm / load arm.
• Evaluate options: longer rod increases total length (boosts effort arm if pivot fixed relative to effort); pivot closer to tank shortens load arm.

Why A is correct:

• Longer rod lengthens effort arm; pivot closer to tank shortens load arm; both raise mechanical advantage per lever formula MA = effort arm / load arm.

Why the others are wrong:

• B: Shorter rod shortens effort arm; pivot further lengthens load arm; lowers MA.
• C: Longer rod lengthens effort arm, but pivot further lengthens load arm more proportionally; does not guarantee higher MA.
• D: Shorter rod shortens effort arm; pivot further lengthens load arm; lowers MA.

Final answer: A