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

AngelwasaGeo

2 years ago

Firstly we need to outline our perimeters.
E=50N, Ef=40%, V.R=6 by counting the number of tackles in the diagram. L=?
Ef= MA /V.R x 100%.
Substitution the values,
40=MA/6x100%.
By Cross multiplying,
MA= 240.
Mechanical Advantage is the same thing as L/E.
L/E=240/100.
Cross multiplying
100L=240*50
100L=12000
Divide both sides by 100 to make L The subject of a formula.
100L/100=12000/100

Therefore, Load (L) =120N