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प्रश्न
A pulley system has three pulleys. A load of 120 N is overcome by applying an effort of 50 N. Calculate the Mechanical Advantage and Efficiency of this system.
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उत्तर
Given: Load = 120 N
E = 50 N
Number of pulleys (n) = 3
For this pulley system,
V.R. = 3
1) Mechanical advantage of pulley system is
M.A. = `L/E`
= `120/50`
= 2.4
2) The efficiency of the system is
`eta = (M.A.)/(V.R.)`
= `(2.4)/n`
= `2.4/3`
= 0.8
= 80 %
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