Draw a Neat Labelled Diagram Showing Forces Acting on the Meniscus of Water in a Capillary Tube. - Physics


Draw a neat labelled diagram showing forces acting on the meniscus of water in a capillary tube.



r = radius of capillary tube

h = height of liquid level in the tube

T = surface tension of liquid

ρ = density of liquid

g = acceleration due to gravity

Concept: Surface Tension
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2014-2015 (October)


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`(b) 4pir^2T[n^(1/3)-1]`

`(c) 4piR^2T[n^(2/3)-1]`

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How much amount of work is done in forming a soap bubble of radius r?

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Numerical Problem.

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Distinguish between cohesive and adhesive forces.

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  1. liquid drop
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  3. air bubble

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(T = surface tension of soap solution).

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Water rises upto a height h in a capillary tube on the surface of the earth. The value of h will increase, if the experimental setup is kept in [g = acceleration due to gravity]

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A coaxial cylinder made of glass is immersed in liquid of surface tension ' S'. Radius of inner and outer surface of cylinder are R1 and R2 respectively. Height till which liquid will rise is (Density of liquid is p):

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Find the work done when a drop of mercury of radius 2 mm breaks into 8 equal droplets. [Surface tension of mercury = 0.4855 J/m2].

Calculate (i) the pressure due to the weight of the water at a depth of 2.5 m and (ii) the depth below the surface of water at which the pressure due to the weight of the water equals 1.0 atm.

The surface tension of boiling water is ______.

A drop of water of radius 8 mm breaks into number of droplets each of radius 1 mm. How many droplets will be formed?

Define angle of contact.


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