A block and tackle pulley arrangement has 6 pulleys in which an effort of 50N supports a load of 200N, calculate the efficiency of the machine
A
80.0%
B
76.6%
C
66.7%
D
60.7%
Verified Correct Answer: C.
Physical Principles & Numerical Solution
Efficiency = \(\frac{ma}{V.R}\) x \(\frac{100}{1}\)
V.R = number of pulleys = 6
ma = \(\frac{\text{Load}}{\text{Effort}}\) = \(\frac{200}{50}\) = 4
Effiecieny = \(\frac{4}{6}\) × 100 = 66.67%
Source: Myschool Past Questions Archive (Record #46389)