If An Air Bubble Of Same Radius Be Formed At A Depth Of 40.0 Cm In A Soap Solution (relative Density 1.20), Then What Will Be The Pressure Inside The Air Bubble?

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If an air bubble of same radius be formed at a depth of 40.0 cm in a soap solution (relative density 1.20), then what will be the pressure inside the air bubble?


Correct option is


The excess pressure in an air bubble of same radius R formed near the surface of a soap solution is


If P be the atmospheric pressure, then the pressure at a depth h (= 40.0 cm = 40.0  10–2) in a soap solution of density  is 


The relative density of soap solution (relative to density of water which is 103 kg/m3) is 1.20. Hence the density of soap solution is


Here h = 40.0 cm = 0.40 m. 



Putting values of P and  in eq. (i), we get  



 total pressure inside the air bubble is  






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