A wheel and axle have radii 80cm and 10cm respectively. If the efficiency of the machine is 0.85, an applied force of 1200N to the wheel will raise a load of
A
8.0N
B
6.8N
C
8160N
D
9600N
Verified Correct Answer: C.
Physical Principles & Numerical Solution
Efficiency = m.A x \(\frac{1}{V.R}\) x 100%
85 = \(\frac{load}{1200}\) x \(\frac{10}{80}\) x \(\frac{100}{1}\)
load = 8160N
Source: Myschool Past Questions Archive (Record #28135)