How does an oil lamp produce light through a wick that is lit using a match?

The height up to which water will rise in a capillary tube will be

$A$ 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:

If $M$ is the mass of water that rises in a capillary tube of radius $r,$ then the mass of water which will rise in a capillary tube of radius $2r$ is

Two narrow tubes of diameters $d_1$ and $d_2$ are joined together to form a $U$-tube open at both ends. If the $U$-tube contains water,the difference in water levels in the limbs is ($T$ is the surface tension of water,the angle of contact is zero,the density of water is $\rho$,and $g$ is the acceleration due to gravity).

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 $......^{\circ}$.