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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
Give one example of a class I lever where mechanical advantage is more than one ?
Fig 3.17 below shows a lever in use.

(a) To which class of lever does it belong?
(b) If FA = 80 cm, AB = 20 cm, find its mechanical advantage.
(c) Calculate the value of E.
The following belong to which class of lever?
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The following belong to which class of lever?
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The following belong to which class of lever?
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Shears, used for cutting metals and scissors used for cutting clothes are both examples of levers of the first order. However, whereas the shears always have short blades and long handles, the scissors often have blades much longer than the handles. Explain, why this is so?
In the diagram shown alongside a claw hammer, mark the fulcrum (F) and indicate the directions of load (L) and effort (E) with arrows. What class of lever is it? Give one more example of this class of lever.

A crowbar of length 100 cm is used to lift a load of 5 kgf. It has its fulcrum at a distance of 20 cm from the load. Calculate:
(i) the mechanical advantage of a crowbar and,
(ii) the effort applied at the other end.
A lever is used to multiply the force.
