The fiqure above represents a block-and-tackle pulley system on which an effort of W Newtons…

The fiqure above represents a block-and-tackle pulley system on which an effort of W Newtons supports a load of 120.0N. If the efficiency of the machine is 40(^o), then the value of W is 

Correct Answer: Option D

Explanation

V.E = 6, load = 120N 

Efficiency = M.A x (frac{1}{V.R}) x 100%

40 = (frac{120}{effort}) x (frac{1}{6}) x (frac{100}{1}) 

Effort = 50N

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