Properties Of Solids And Liquids Question 316
Question: The volume of an air bubble becomes three times as it rises from the bottom of a lake to its surface. Assuming atmospheric pressure to be 75 cm of Hg and the density of water to be 1/10 of the density of mercury, the depth of the lake is [AMU 1995]
Options:
A) 5 m
B)10 m
C) 15 m
D)20 m
Show Answer
Answer:
Correct Answer: C
Solution:
$ P _{1}V _{1}=P _{2}V _{2} $
therefore $ (H _{Hg}{\rho _{Hg}}+H _{W}{\rho _{W}})V=H _{Hg}{\rho _{Hg}}\times 3V $
therefore $ H _{Hg}{\rho _{Hg}}+H _{W}\frac{{\rho _{Hg}}}{10}=3H _{Hg}{\rho _{Hg}} $
therefore$ H _{W}=2H _{Hg}\times 10 $
$ =\frac{2\times 75\times 10}{100}=15m $
