If the surface tension of a soap solution is $0.03\, MKS$ units, then the excess of pressure inside a soap bubble of diameter $6 \,mm$ over the atmospheric pressure will be

Consider the following two statement $A$ and $B$, and identify the correct choice in the given answers

$A :$ The excess pressure inside a small liquid drop is more than that of a big drop.

$B :$ As the aeroplane moves fast on the runway the pressure is more on the upper surface of its wings and less on the bottom surface of the wings.

A hot air balloon is a sphere of radius $8$ $m$. The air inside is at a temperature of $60^{°}$ $C$. How large a mass can the balloon lift when the outside temperature is $20^{°}$ $C$ ? Assume air is an ideal gas, $R = 8.314\,J\,mol{e^{ - 1}},1\,atm = 1.013 \times {10^5}{P_a},$ the membrane tension is $= 5\,N/m$.

Two narrow bores of diameter $5.0\, {mm}$ and $8.0\, {mm}$ are joined together to form a $U-$shaped tube open at both ends. If this ${U}$-tube contains water, what is the difference in the level of two limbs of the tube.

[Take surface tension of water ${T}=7.3 \times 10^{-2} \, {Nm}^{-1}$, angle of contact $=0, {g}=10\, {ms}^{-2}$ and density of water $\left.=1.0 \times 10^{3} \,{kg} \,{m}^{-3}\right]$ (in $mm$)

Air (density $\rho$ ) is being blown on a soap film (surface tension $T$ ) by a pipe of radius $R$ with its opening right next to the film. The film is deformed and a bubble detaches from the film when the shape of the deformed surface is a hemisphere. Given that the dynamic pressure on the film due to the air blown at speed $v$ is $\frac{1}{2} \rho v^{2}$, the speed at which the bubble formed is

A spherical soap bubble of radius $3\,cm$ is formed inside another spherical soap bubble of radius $6\,cm$. If the internal pressure of the smaller bubble of radius $3\,cm$ in the above system is equal to the internal pressure of the another single soap bubble of radius $r\,cm$. The value of $r$ is.......