A machine of efficiency 80% is used to lift a box. If the effort applied by the machine is twice the weight of the box. Calculate the velocity ratio of the machine
A
0.50
B
0.63
C
0.80
D
1.60
Verified Correct Answer: B.
Physical Principles & Numerical Solution
Y = \(\frac{M.A}{V.R} \times \frac{100}{1}\)
= \(\frac{\frac{1}{2}}{V.R} \times \frac{100}{1}\)
V.R = 0.625
Source: Myschool Past Questions Archive (Record #35169)