$A$ 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?

Why does the mercury level fall in a capillary tube? Explain.

Water rises to a height of $10 \,cm$ in a capillary tube. In which of the following conditions will it rise to a height much greater than $10 \,cm$ in a very long capillary tube?

When a long glass capillary tube of radius $0.015 \; cm$ is dipped in a liquid,the liquid rises to a height of $15 \; cm$ within it. If the contact angle between the liquid and glass is close to $0^{\circ}$,the surface tension of the liquid,in $milliNewton \; m^{-1}$ is $.....$
$[\rho_{\text{liquid}} = 900 \; kg \; m^{-3}, g = 10 \; ms^{-2}]$ (Give answer in closest integer)

Two capillary tubes $A$ and $B$ of the same internal diameter are kept vertically in two different liquids whose densities are in the ratio $4:3$. If the surface tensions of these two liquids are in the ratio $6:5$,then the ratio of rise of liquid in capillary $A$ to that in $B$ is (assume their angles of contact are nearly equal).

On putting a capillary tube in a pot filled with water,the level of water rises up to a height of $4 \,cm$ in the tube. If a tube of half the diameter is used instead,the water will rise to a height of nearly ............. $cm$.