﻿   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? : Kaysons Education

# 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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## Question

### Solution

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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Testing

#### SIMILAR QUESTIONS

Q1

A non-viscous liquid of constant density 1000 kg/m3 flows in a streamline motion along a tube of variable cross-section. The tube is kept inclined in the vertical plane as shown in figure. The area of cross-section of the tube at two points P and Q at heights of 2 metre and 5 metre are respectively  the velocity of the liquid at point P is 1 m/s. Find the work done per unit volume by the pressure and the gravity forces as the fluid flows from point P to Q.

Q2

The fresh water behind a reservoir dam is 15 m deep. A horizontal pipe 4.0 cm in diameter passes through the dam 6.0 m below the water surface as shown in figure. A plug secures the pipe opening. The plug is removed. What volume of water flows out of the pipe in 3.0- hour?

Q3

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Q4

The surface tension of a soap solution is 0.03 N/m. How much work is required to form a bubble of 1.0 cm radius from this solution?

Q5

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Q6

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What will be the ratio between the total surface energy of the droplets and the surface energy of the big drop?

Q7

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Q8

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Q9

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Q10

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