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

Options

A. 5 m
B. 10 m
C. 15 m
D. 20 m

Answer

C

Explanation

If temperature remains constant, then
`p_(1)V_(1)=p_(2)V_(2)`
`(75+h)V=(75)(3V)`
`therefore " " h=150 cm " of" Hg`
=1.5 m of Hg or 15 m of water