Maximum Capillary Rise: Dynamic Treatment of Liquid in Motion?

AI Thread Summary
The discussion centers on the formula for capillary rise, which is influenced by surface tension and the geometry of the surrounding reservoir. The maximum height is derived from the equation 2σ/(ρgr) when cos(θ)=1, applicable in cases with an infinite reservoir. However, participants question how a narrower surrounding might affect this height. A dynamic treatment of the liquid in motion is suggested as necessary for a more accurate analysis. Clarifications on the phrasing of the problem statement are also noted as potentially impacting the interpretation of the answer.
Rituraj131
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Homework Statement
A capillay tube is just in contact with a liquid surface of perfectly wetting liquid. What is the maximum height liquid can rise inside the capilary?
Relevant Equations
H=2σcos(θ)/(ρgr)
I know that the height in general is goven by 2σcos(θ)/(ρgr). So the maximum height can be 2σ/(ρgr) with cos(θ)=1. But the answer given is c.
 

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Rituraj131 said:
I know that the height in general is goven by 2σcos(θ)/(ρgr).
That is for the case where the surrounding reservoir is effectively infinite in area. How do you think it might be affected by a narrower surround?
(But I am not sure this gets to answer c.)
 
haruspex said:
That is for the case where the surrounding reservoir is effectively infinite in area. How do you think it might be affected by a narrower surround?
(But I am not sure this gets to answer c.)
Thank you for you response. Actually the problem needs a dynamic treatment of the liquid in motion
 
Rituraj131 said:
Thank you for you response. Actually the problem needs a dynamic treatment of the liquid in motion
Ah, ok... you unintentionally altered the statement by writing "is just in contact" instead of "is put in contact".

Does this mean you now get the intended answer?
 
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