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Question
The length of a nut-cracker is 12 cm. A nut, when kept at a distance of 4 cm from its fulcrum, requires an effort of 100 gf to crack it. What force will be required to crack the nut without using the nut-cracker?
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Solution
Given : Effort arm = 12 cm, Load arm = 4 cm, Effort E = 100 gf, Load L = ?
(Nut-cracker is the lever of second order)
Since, `"Load"/"Effort"=("Effort arm")/("Load arm")`
∴ `"L"/100=12/4`
or L = 300 gf.
Thus, a force of 300 gf is required to crack the nut without using the nut-cracker.
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