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Question
Which class of lever found in the human body is being used by a boy when he raises the weight of his body on his toes?
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Solution
Class II lever.
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The lever for which the mechanical advantage is less than 1 has :
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A man uses a crowbar of length 1.5 m to raise a load of 75 kgf by putting a sharp edge below the bar at a distance 1 m from his hand.
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