﻿ A small drop of water of surface tension  is squeezed between two clean glass plates so that a thin layer of thickness d and area A is formed between them. If the angle of contact is zero, the force required to pull the plates apart is  : Kaysons Education

# A Small Drop Of Water Of Surface Tension  is Squeezed Between Two Clean Glass Plates So That A Thin Layer Of Thickness d and Area A is Formed Between Them. If The Angle Of Contact Is Zero, The Force Required To Pull The Plates Apart Is

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## Question

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Correct option is

An extremely thin layer of a liquid can be regarded as a collection of a large number of semi-spherical drops. Hence the excess pressure across a thin layer of a liquid is  as in the case of a spherical drop, where r = d/2. Therefore, excess pressure is

Force due to surface tension pushing the two plates together is

F = excess pressure  area of layer

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