Two parallel glass plates are dipped partly in the liquid of density 'd' keeping them vertical. If the distance between the plates is 'x', surface tension for liquids is T and angle of contact is θ then rise of liquid between the plates due to capillary will be

Let the width of each plate is b and due to surface tension, liquid will rise upto height h. Then upward force due to surface tension = 2Tb cosθ….(i)weight of the liquid that rises in between the plates=Vdg=(bxh)dg Equating (i) and (ii), we get 2Tcos⁡θ=bxhdgh=2Tcos⁡θxdg