A block and tackle is used to raise a load of 250N through a vertical distance of 30m. What is the efficiency of the system if the work done against friction is 1500J?
A
62.5%
B
73.3%
C
83.3%
D
94.3%
Verified Correct Answer: C.
Physical Principles & Numerical Solution
Y = \(\frac{work output}{work input} \times \frac{100}{1}\)
Y = \(\frac{250 \times 30}{250 \times 30 + 1500} \times \frac{100}{1}\)
Source: Myschool Past Questions Archive (Record #27385)