The rise of a Liquid in a capillary tube is due to

Concept:

• Capillary action: If one end of a capillary tube is put into a liquid that wets glass, it is found that the liquid rises into the capillary tube to a certain height.
• This rise is due to inward pull of surface tension acting on the surface which pushes the liquid into the capillary tube.

The height of the liquid rises or fall (h) is given by

\({\rm{h}} = \frac{{4{\rm{\;T}}\cos {\rm{\theta }}}}{{{\rm{d\;\rho \;g}}}}\)

Where T = surface tension, θ = angle of contact, d = diameter of capillary tube, ρ = density of liquid, g = acceleration due gravity.

Explanation:

Hence the rise in capillary action is due to surface tension.