$A$ liquid column of height $0.04 \,cm$ balances excess pressure of a soap bubble of a certain radius. If the density of the liquid is $8 \times 10^3 \,kg \,m^{-3}$ and the surface tension of the soap solution is $0.28 \,N \,m^{-1}$, then the diameter of the soap bubble is . . . . . . $cm$.
$(g = 10 \,m \,s^{-2})$

One end of a uniform glass capillary tube of radius $r = 0.025 \ cm$ is immersed vertically in water to a depth $h = 1 \ cm$. The excess pressure in $N/m^2$ required to blow an air bubble out of the tube is: (Surface tension of water $T = 7 \times 10^{-2} \ N/m$, Density of water $\rho = 10^3 \ kg/m^3$, Acceleration due to gravity $g = 10 \ m/s^2$)

$A$ soap bubble assumes a spherical surface. Which of the following statements is wrong?

$A$ big water drop is divided into $8$ equal droplets. $\Delta P_{S}$ and $\Delta P_{B}$ are the excess pressure inside a smaller and bigger drop respectively. The relation between $\Delta P_{S}$ and $\Delta P_{B}$ is

If the excess pressure inside a soap bubble is balanced by an oil column of height $2\, mm$,then the surface tension of the soap solution will be $(r = 1\, cm$ and density $d = 0.8\, g/cm^3)$.

$A$ water drop of radius '$r$' and volume '$V$' is kept between two identical glass plates such that it forms a thin layer of area '$A$' between the plates. $A$ force '$F$' is applied such that the two plates separate from each other. The surface tension '$T$' of the liquid is: