$A$ square frame of each side $L$ is dipped in a soap solution and taken out. The force acting on the film formed is ($T =$ surface tension of soap solution). (in $TL$)

The surface tension of most of the liquids decreases with a rise in:

Which one of the following statements is correct?

$A$ wooden stick $2 \, m$ long is floating on the surface of water. The surface tension of water is $0.07 \, N/m$. By putting soap solution on one side of the stick,the surface tension is reduced to $0.06 \, N/m$. The net force on the stick will be ....... $N$.

The force necessary to pull a circular plate of $5\, cm$ radius from a water surface,for which the surface tension is $75\, dynes/cm$,is

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