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The process of wetting of a solid surface is better explained with cohesive and adhesive forces. Wetting of a solid surface by a liquid means the liquid molecules succeeded in maintaining a contact with the surface through the inter molecular attractive forces. You should see that every liquid may not stick on to a given surface and similarly every surface ...


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chemistry better describes the difference between adhesion atoms in mercury vs hydrogen bonding in water. Mercury has boiling over 600f vs only 212 f for water shows the amount of heat energy to break bonds hold the respective particles together.


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Very interesting experiment you did! 1. The effect of surface tension due to the water/rubber and rubber/air interfaces is negligible. For a radius of $R = 10$ cm, and taking a typical surface tension of $\gamma = 70$ mN/m, the increase of pressure in the balloon because of the interfaces is typiclally of the order of the Laplace pressure $\Delta p = 2 ...


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You can think of the force as arising due to the energy associated with the air-fluid interface. The force is a change in energy per unit distance. The surface contact of the fluid with the ring does have an energy associated with it, but this energy is constant as the ring is lifted out of the water, and thus does not contribute to the surface tension. ...


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It seems to me it might depend on the material the ring made of. After a bit of poking around Amazon book previews I managed to find page 19 of "Physics and Chemistry of Interfaces" by Butt, Hans-J├╝rgen; Graf, Karlheinz; Kappl, Michael (2003). This is the source cited by the Wikipedia article you got the equation from. The next sentence, immediately ...


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It was a good thaught of you and was similar to mine,I do not have any theoretical answer but according to my understanding : An air bubble inside water will experience a lot of inward pressure than what it can exert outward as it is inside a denser medium , and a water droplet in air will exert a more pressure outwards than what it experiences from air ...


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You need to read about Laplace Pressure which is "the pressure difference between the inside and the outside of a curved surface that forms the boundary between a gas region and a liquid region". And given by where $\gamma$ is surface tension. For a droplet of radius $R$ the above equation reduces to The pressure difference between outside and inside ...


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I agree that it is confusing but I think that the author looked at the gas which is bulging out and called that surface the convex side (cf convex glass lens) and then looked at the liquid which is concave in shape.



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