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 $\theta$ 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 cos$\theta$….(i)

weight of the liquid that rises in between the plates

$=Vdg=\left(bxh\right)dg$

$\text{ Equating (i) and (ii), we get }2T\cos \theta =bxhdg$

$h=\frac{2T\cos \theta }{xdg}$