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Topic: capillary forces  (Read 4941 times)

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Offline kapital

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capillary forces
« on: August 25, 2012, 05:05:08 AM »
Why does a liquid that weat surface, form a concave meniscus? And where does the pressure come, that lifts fludid in capillary?

Thanks for answer.

Offline MrTeo

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The way of the superior man may be compared to what takes place in traveling, when to go to a distance we must first traverse the space that is near, and in ascending a height, when we must begin from the lower ground. (Confucius)

Offline kapital

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Re: capillary forces
« Reply #2 on: August 27, 2012, 04:56:37 AM »
I have read this. I still do not know where there is pressure, that lifts fluid in capillary.
Can please somebody tell me this.

Offline Borek

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Re: capillary forces
« Reply #3 on: August 27, 2012, 05:30:01 AM »
There is no pressure pushing the fluid, there is a force that pulls the liquid up - and this force acts on the phase boundary (which is where the contact angle comes into play).
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Offline kapital

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Re: capillary forces
« Reply #4 on: August 27, 2012, 05:40:14 AM »
Where does this forse arise from?

Or why there is not flat surface in capillary?(but curved)

Offline Borek

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Re: capillary forces
« Reply #5 on: August 27, 2012, 06:38:02 AM »
It is all about intermolecular forces, which are different between molecules of liquid and between molecules of liquid and solid (walls of the tube).
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Offline kapital

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Re: capillary forces
« Reply #6 on: August 27, 2012, 09:01:29 AM »
Ok. But still, why doest that make a curved surfase and cappilary flow?

Offline curiouscat

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Re: capillary forces
« Reply #7 on: August 27, 2012, 09:19:03 AM »
Ok. But still, why doest that make a curved surfase and cappilary flow?

What textbook are you using?

Offline kapital

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Re: capillary forces
« Reply #8 on: August 27, 2012, 10:36:20 AM »
Why? Atkins physical chemistry

Offline kapital

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Re: capillary forces
« Reply #9 on: August 27, 2012, 10:53:30 AM »
And there is some mension of pressure on page 643. 

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