Physics, asked by vandanabindlish2677, 9 months ago

Derive an expression for capillary rise for a liquid having a concave mirror

Answers

Answered by rohanpawar10906
5

Capillarity is a physical phenomenon in which liquids flow without the help of

gravity.  Liquids even rise to a height against gravity, through narrow

tubes.

     Capillary action is due to the phenomenon of Surface tension of liquid as well

as adhesive forces between liquid molecules and molecules of the narrow tube.

Surface tension is due to cohesive attraction among liquid molecules.

Derivation:

    When a thin (open or closed at the top) tube is inserted into a liquid in a

container, the liquid inside the tube rises to a height h above the liquid

surface outside.  Let the diameter of the tube be D.  The density of

liquid be ρ.  The surface tension of the liquid be S.

Weight of liquid column acting downwards = m g

   

    W = ρ (πD²/4) h g     --(1)

    The surface on the top liquid inside the capillary tube has a trough (cup) like

shape. Assume the angle of contact with the walls be Ф.  Surface

tension is the contact force per unit length along the circumference of top

surface. This force pulls the liquid vertically upwards.

   

Force upwards = S * πD * CosФ  ----- (2)

=>  

 h =  4 S CosФ / (ρ D g)  

Explanation:

please mark as brainlest answer

Answered by devikad849
5

Explanation:

I think it's useful for you

Attachments:
Similar questions