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Question
Which class of lever found in the human body is being used by a boy when he holds a load on the palm of his hand.
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Solution
Class III lever.
RELATED QUESTIONS
Write down a relation expressing the mechanical advantage of a lever.
A lever of length 9 cm has its load arm 5 cm long and the effort arm is 9 cm long.
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The diagram shows the use of a lever.
- State the principle of moments as applied to the above lever.
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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?
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:
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(ii) the effort applied at the other end.
