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Question
A coolie is pushing a box weighing 1500 N up an inclined plane 7.5 m long on to a platform, 2.5 m above the ground.
(i) Calculate the mechanical advantage of the inclined plane. (ii) Calculate the effort applied by the coolie.
(iii) In actual practice, the coolie needs to apply more effort than what is calculated. Give one reason why you think the coolie needs to apply more effort.
Solution
(i) Mechanical Advantage (M.A.) = `"l"/"h"`
M.A. =`7.5/2.5=3`
(ii) M.A. =`("Load"("L"))/("Effort"("E"))`
3 = `(1,500)/"E"`
E = 500 N.
(iii) More effort is required becaues of friction.
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