The force required to take away a flat circular plate of radius $2 \ cm$ from the surface of water is $[$ Surface tension of water $= 70 \times 10^{-3} \ Nm^{-1}, \pi = \frac{22}{7} ]$

$A$ drop of liquid of density $\rho$ is floating half-immersed in a liquid of density $\sigma$ and surface tension $T = 7.5 \times 10^{-4} \, N \, cm^{-1}$. The radius of the drop in $cm$ will be: (Take: $g = 10 \, m/s^2$)

If the work done in increasing the size of a soap film from $10\;cm \times 6\;cm$ to $10\;cm \times 11\;cm$ is $2 \times 10^{-4}\;J$,then the surface tension is:

Soap solution is used for cleaning dirty clothes because

Water is filled up to a height $h$ in a beaker of radius $R$ as shown in the figure. The density of water is $\rho$,the surface tension of water is $T$ and the atmospheric pressure is $P_0$. Consider a vertical section $ABCD$ of the water column through a diameter of the beaker. The force on water on one side of this section by water on the other side of this section has magnitude

At critical temperature,the surface tension of a liquid is