Asked Jan 11, 2020

Show that there exist an excess pressure inside a curved liquid surface.


Expert Answer

Step 1

Step 1

The force due to surface tension always acts normal to the surface in inward direction on the molecule of a liquid drop. For the condition of equilibrium to be satisfied, there must exist excess pressure inside it.Physics homework question answer, step 1, image 1

Physics homework question answer, step 1, image 2
Step 2

Step 2

Let R be the radius of a drop and dR be the increase in its radius by small amount due to excess pressure

The work done by excess pressure = force X displacement 

Increase in the area of the drop id given as 

Physics homework question answer, step 2, image 1
Step 3

Step 3


Increase in the surface energy of the drop = Increase in area X Surface tension

Now work done by exce...

Physics homework question answer, step 3, image 1

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Fluid Mechanics

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