The diagram represents a block-and-tackle pulley system o...
The diagram represents a block-and-tackle pulley system on which an effort of 50N is just able to lift a load of weight W. If the efficiency of the machine is 40%. find the value of W
300N
200N
140N
120N
20N
Correct answer is D
Eff = MAVR x 100%
40 = MA60
MA = 240
LE=240100
W = L = 240100 x 50
= 120N
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