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Question
A pulley system has three pulleys. A load of 120 N is overcome by applying an effort of 50N. Calculate the Mechanical Advantage and Efficiency of this system.
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Solution
Load = 120 N; E = 50 N; n = 3
Mechanical advantage of pulley system is
M.A. = `L/E = 120/50` = 2.4
The efficiency of the system is
`eta = ("M.A.")/("V.R.") = (2.4)/n = 2.4/3 = 0.8 = 80%`
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