Properties Of Solids And Liquids Question 227
Question: Water is flowing through a tube of non-uniform cross-section ratio of the radius at entry and exit end of the pipe is 3 : 2. Then the ratio of velocities at entry and exit of liquid is [RPMT 2001]
Options:
A) 4 : 9
B) 9 : 4
C) 8 : 27
D) 1 : 1
Show Answer
Answer:
Correct Answer: A
Solution:
If velocities of water at entry and exit points are v1 and v2, then according to equation of continuity,
$ A _{1}v _{1}=A _{2}v _{2} $
therefore $ \frac{v _{1}}{v _{2}}=\frac{A _{2}}{A _{1}}={{\left( \frac{r _{2}}{r _{1}} \right)}^{2}}={{\left( \frac{2}{3} \right)}^{2}}=\frac{4}{9} $