Fluid Mechanics Viscosity Question 90
Question: Two water pipes of diameters 2 cm and 4 cm are connected with the main supply line. The velocity of flow of water in the pipe of 2 cm diameter is[MNR 1980]
Options:
A)4 times that in the other pipe
B)$ \frac{1}{4} $ times that in the other pipe
C)2 times that in the other pipe
D)$ \frac{1}{2} $ times that in the other pipe
Show Answer
Answer:
Correct Answer: A
Solution:
$ d_{A}=2,cm $ and$ d_{B}=4\ cm $ $ \therefore \ \ r_{A}=1\ cm $ and $ r_{B}=2\ cm $ From equation of continuity,av = constant \ $ \frac{v_{A}}{v_{B}}=\frac{a_{B}}{a_{A}}=\frac{\pi {{(r_{B})}^{2}}}{\pi {{(r_{A})}^{2}}}={{\left( \frac{2}{1} \right)}^{2}}\Rightarrow v_{A}=4v_{B} $
BETA
