QQuestion
- Case 1: 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:
(a) In which case (1st or 2nd) was the potato closer to her hand applying the effort? (Assume normal reaction of the surface of the potato is same in both cases)
(b) Give a reason for your answer in (a) above.
✓Answer
(a) The potato was closer to her hand in Case 1.
(b) The cutter acts as a Class II lever, in which the load lies between the fulcrum and the effort. When the potato is placed closer to the hand applying effort, it is farther from the fulcrum, so the load arm becomes longer. For a fixed effort arm, a longer load arm requires greater effort to cut. Since E1 > E2, the potato must have been closer to her hand in Case 1.
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