The excess pressure inside a soap bubble of radius $0.5 \ cm$ is balanced by the pressure due to an oil column of height $4 \ mm$. If the density of the oil is $900 \ kg \ m^{-3}$,then the surface tension of the soap solution is (Acceleration due to gravity $= 10 \ m \ s^{-2}$)

$A$ container,whose bottom has round holes with diameter $0.1 \ mm$ is filled with water. The maximum height in $cm$ up to which water can be filled without leakage will be ........ $cm$. (Surface tension $= 75 \times 10^{-3} \ N/m$ and $g = 10 \ m/s^2$)

$A$ liquid drop of volume $V$ is placed on the surface of a glass plate. Then,another glass plate is placed on it such that the liquid forms a thin layer of area $A$ between the surfaces of the two plates. To separate the plates,a force $F$ has to be applied normal to the surfaces. The surface tension of the liquid is

There is an air bubble of radius $1.0\,mm$ in a liquid of surface tension $0.075\,N\,m^{-1}$ and density $1000\,kg\,m^{-3}$ at a depth of $10\,cm$ below the free surface. The amount by which the pressure inside the bubble is greater than the atmospheric pressure is $....Pa \left( g = 10\,m\,s^{-2} \right)$

The lower end of a capillary tube of diameter $2.00 \; mm$ is dipped $8.00 \; cm$ below the surface of water in a beaker. What is the pressure required in the tube in order to blow a hemispherical bubble at its end in water? The surface tension of water at the temperature of the experiment is $7.30 \times 10^{-2} \; N m^{-1}$. Atmospheric pressure $= 1.01 \times 10^{5} \; Pa$,density of water $= 1000 \; kg m^{-3}$,$g = 9.80 \; m s^{-2}$. Also,calculate the excess pressure.

Two spherical soap bubbles of radii $r_1$ and $r_2$ in vacuum combine under isothermal conditions. The resulting bubble has a radius equal to: