A water drop of radius 'r' and volume 'V' is | vedclass

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(A) Consider complete wetting of the glass plates by the liquid.The pressure difference (Laplace pressure) across the curved surface of the liquid is

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$\frac{F V}{2 A^2}$

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(A) Consider complete wetting of the glass plates by the liquid.The pressure difference (Laplace pressure) across the curved surface of the liquid is given by $\Delta P = \frac{T}{R}$,where $R$ is the radius of curvature of the meniscus.This pressure difference creates an attractive force between the plates,given by $F = \Delta P \cdot A = \frac{T}{R} \cdot A$,so $\frac{T}{R} = \frac{F}{A} \quad \dots(1)$Assuming the liquid forms a thin cylindrical layer of thickness $d$ and area $A$,the volume $V$ is given by $V = A \cdot d$.For a meniscus with radius of curvature $R$,the thickness of the layer is $d = 2R$,so $V = A(2R)$.Thus,$R = \frac{V}{2A} \quad \dots(2)$Substituting equation $(2)$ into equation $(1)$:$\frac{T}{(V / 2A)} = \frac{F}{A}$$T = \frac{F \cdot V}{2A^2}$

$A$ water drop of radius '$r$' and volume '$V$' is kept between two identical glass plates such that it forms a thin layer of area '$A$' between the plates. $A$ force '$F$' is applied such that the two plates separate from each other. The surface tension '$T$' of the liquid is:

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