Two capillary tubes $P$ and $Q$ are dipped vertically in water. The height of water level in capillary tube $P$ is $\frac{2}{3}$ of the height in capillary tube $Q$. The ratio of their diameters is

$A$ vertical glass capillary tube open at both ends contains some water. Which of the following shapes may be taken by the water in the tube?

$A$ $U$-tube with limbs of diameters $5\, mm$ and $2\, mm$ contains water of surface tension $7 \times 10^{-2} \, N/m$. The angle of contact is zero and the density of water is $10^3 \, kg/m^3$. If $g = 10 \, m/s^2$,then the difference in the liquid levels of the two limbs is:

Water rises to a height of $16.3 \,cm$ in a capillary tube. If the tube is cut at a height of $12 \,cm$ above the water level,what will happen?

Two capillaries made of the same material have radii $r_1 = 1 \, mm$ and $r_2 = 2 \, mm$. If the rise of the liquid in the first capillary $(r_1 = 1 \, mm)$ is $30 \, cm$,then the rise in the other capillary will be ........ $cm$.

The sap in trees,which consists mainly of water in summer,rises in a system of capillaries of radius $r = 2.5 \times 10^{-5} \ m$. The surface tension of sap is $T = 7.28 \times 10^{-2} \ N/m$ and the angle of contact is $0^{\circ}$. Does surface tension alone account for the supply of water to the top of all trees?