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Question
The diagram below shows a lever in use.

(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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Solution
(i) Class 2 lever.
(ii) We know,
L × LA = E × EA.
M.A. =`"L"/"E"=("EA")/("LA")`
= `100/40`
= 2.5
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