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प्रश्न
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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उत्तर
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.
संबंधित प्रश्न
State the principle of a lever?
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- Draw a diagram of the arrangement showing the fulcrum (F), load (L) and effort (E) with their directions.
- State the kind of lever.
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- Draw a diagram of the lever showing the position of fulcrum F and directions of both the load L and effort E.
- What is the mechanical advantage and velocity ratio if the efficiency is 100%?
- What will be the mechanical advantage and velocity ratio if the efficiency becomes 50%?
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(i) To which class of lever does it belong?
(ii) If FA = 40 cm, AB = 60 cm, then find the mechanical advantage of the lever.
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