Question

Case I: Lata cuts a potato into two halves, using a cutter which belongs to a Class II lever. She needed effort E₁.

Case 2: Then she cuts one half of this potato again, but this time she needed effort E₂. If E₁ > E₂ then:

1. In which case (1^st or 2^nd) was the potato closer to her hand applying the effort? (Assume normal reaction of the surface of the potato is same in both cases)

2. Give a reason for your answer in (a) above.

Answer 1

1. The potato was closer to her hand in Case 1.
2. It is a Class II lever, which means that the load is between the pivot and the effort. Since the potato is farther from the fulcrum when it is closer to the hand that is exerting force, the lever arm gets longer. It takes more work to cut a longer lever arm with a shorter effort arm. The potato must have been closer to her hand in Case 1 since E₁ > E₂.