Liquid rises to a height $2 \ cm$ in a capillary tube; in that case,the angle of contact between the solid and the liquid is $0^{\circ}$. The tube is lowered more now,so that the capillary is only $1 \ cm$ above the liquid. In this case,the angle of contact between the solid and liquid is $......^{\circ}$.

In a capillary tube of radius '$R$',a straight thin metal wire of radius '$r$' is inserted symmetrically and one end of the combination is dipped vertically in water such that the lower end of the capillary and the thin wire are at the same level. If '$T$' is the surface tension of water and '$\rho$' is the density of water, then the rise of water in the capillary is:

When two capillary tubes of different diameters are dipped vertically,the rise of the liquid is

The heat evolved for the rise of water when one end of the capillary tube of radius $r$ is immersed vertically into water is (Assume surface tension $= T$ and density of water to be $\rho$)

$A$ capillary tube is immersed vertically in water,and the water rises to a height $h_1$ on the Earth's surface. When this arrangement is taken into a mine of depth $d$ below the Earth's surface,the height of the water column is $h_2$. If $R$ is the radius of the Earth,the ratio $\frac{h_2}{h_1}$ is:

$A$ liquid (density $= 10^3 \ kg/m^3$) rises to a height of $10 \ cm$ in a capillary tube. If the angle of contact of the liquid-glass pair is $0^{\circ}$ and the radius of the tube is $2 \ mm$,then the surface tension of the liquid is: