Question #4ad26

1 Answer
Aug 24, 2017

Let the volume of the air bubble at the bottom of the lake be Vb. So its volume at the surface Vs=2Vb

Let the depth of the lake be hcm

So pressure at the bottom of the lake

Pb=pressure of water of height h+ atmospheric prssure

Pb=h×dw×g+75×dHg×g

Pressure at the surface

Ps=75×dHg×g

Now applying Boyle's law we get

Pb×Vb=Ps×Vs

(h×dw×g+75×dHg×g)Vb=(75×dHg×g)×2Vb

h+75×dHgdw=75×dHgdw×2

h=75×dHgdw

h=75×403=1000cm=10m