Fluid Mechanics Viscosity Question 252
Question: In a hydraulic lift, compressed air exerts a force $ F_{1} $ on a small piston having a radius of 5 cm. This pressure is transmitted to a second piston of radius 15 cm. If the mass of the load to be lifted is 1350 kg, find the value of$ F_{1} $ ? The pressure necessary to accomplish this task is
Options:
A) $ 1.4\times 10^{5}Pa $
B) $ 12\times 10^{5}Pa $
C) $ 1.9\times 10^{5}Pa $
D) $ 1.9Pa $
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Answer:
Correct Answer: C
Solution:
[c] Since pressure is transmitted undiminished throughout the fluid (Pascal’s law) $ F_{1}=\frac{A_{1}}{A_{2}}F_{2}=\frac{\pi (5\times 5)}{\pi (15\times 15)}(1350\times 9.81) $ $ \approx ,,1.5\times 10^{3}N $ The air pressure that will produce this force is$ P=\frac{F_{1}}{A_{1}}=\frac{1.5\times 10^{3}}{\pi {{(5\times {{10}^{-2}}m)}^{2}}}=1.9\times 10^{5}Pa $
BETA
