Questions tagged [capillary-action]
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When water climbs up a piece of paper, where is the energy coming from?
Take a glass of water and piece of toilet paper. If you keep the paper vertical, and touch the surface of the water with the tip of the paper, you can see the water being absorbed and climbing up the ...
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How is the water meniscus at the edge of a capillary tube?
Suppose we have a capillary tube in which water can rise to a height of x cm.
If we dip the tube such that the height above the surface is less than x, then how will the water meniscus be at the edge ...
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Capillary tube of insufficient length
I was wondering if we have a very thin glass tube placed in a tub of liquid and the portion of the tube outside the liquid is lesser than the height to which the liquid can rise because of capillarity,...
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Capillary action and conservation of energy [duplicate]
When I dip a paper towel in a cup of water the water gets drawn up due to capillary action. How is this reconciled with conservation of energy, as it would seem on the surface that the potential ...
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How does a sponge "suck" up water against gravity?
If I take a sponge and place it in a shallow dish of water (i.e. water level is lower than height of sponge), it absorbs water until the sponge is wet, including a portion of the sponge above the ...
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Molecular origin of solid-liquid and solid-vapour surface tension
I understand that surface tension arises at the liquid-vapour interface due to the asymmetric nature of long-range attractive forces and the short-range repulsive forces acting on the interface where ...
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How is it possible for tall trees to pull water to heights more than 10m?
Which force actually drives water so high up, since pure atmospheric pressure will only get you up to about 10 meters if you're using suction and a long straw and yet tallest trees are over 100 meters ...
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What physical forces pull/press water upwards in vegetation?
Each spring enormous amounts of water rise up in trees and other vegetation. What causes this stream upwards?
Edit: I was under the impression that capillary action is a key factor: the original ...
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Pressure variation in a capillary tube
The following image shows capillary tubes placed in beakers containing water and mercury:
We know that the rise or fall in the level of liquid in a capillary tube is given by Jurin's law:
$$h=\frac{...
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Surface tension and capillarity
The cause of surface tension is said to be asymmetry in the forces experienced by the molecules at the surface due to different interactions with air and liquid, but then the same argument also ...
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Surface tension and capillary rise
The expression for the height rise in a capillary tube is well known, and the surface tension of the liquid air interface is involved. But as I understand the adhesion force between the water and ...
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Capillary pressure for large contact angles
The capillary pressure is calculated according to the following relation.
$$P_{cap} = \dfrac{2\sigma cos\theta}{r}$$
Is this relation valid for all contact angles i.e. $\theta \lt 90^\circ$ and $\...
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Does molten solder flow towards a heat source?
When soldering both plumbing and wiring I have heard the advice that you shoulf apply solid solder opposite to your heat source, since the solder "will flow towards the heat" once it melts.
Is this a ...
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How is sweating a pipe an example of capillary action?
I learned how to sweat a pipe today from my father. If you're not familiar with the process, this might help.
One thing that jumps out at me is this line (from the above link, as well as my father's ...
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Why don't we include the adhesive and cohesive force while calculating rise in a capillary tube?
The contact angle of a liquid solid interface is explained by saying that the liquid surface must be perpendicular to the resultant of adhesive cohesive and gravitational forces acting on it, since it ...
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Capillary action and perpetual motion
From Wikipedia Capillary Action
Thus for a 4 m diameter glass tube in lab conditions given above (radius 2 m), the water would rise an unnoticeable 0.007 mm. However, for a 4 cm diameter tube (radius ...
user74893
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Meniscus in U-shaped capillary?
What does the meniscus look like for a U-shaped capillary?
From similar questions, I learned that the total height (labeled as h) reached by the water in the un-bent capillary is less than the total ...
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Why is there a pressure difference of $h\rho g$ at the top of tube between inner and outer surface in capillary rise?
A glass capillary tube is of the shape of a truncated cone with an apex angle alpha so that it's two ends have cross sections of different radius. When dipped in water vertically, water rises to a ...
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Laplace pressure of a capillary bridge
Laplace pressure is given by $$\Delta p=\gamma \left(\frac{1}{R}+\frac{1}{R'}\right)$$ where $R$ and $R'$ are the radii of the curvature of the surface.
Using the following diagram
the book I'm ...
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