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Surface tension occurs because water molecules attract on another. That means that water prefers to form compact shapes with little surface area. Creating a large, extended area, as you do in a soap bubble, is actually opposed by surface tension. This is why you can't get stable bubbles with pure water: the bubble wants to collapse into a compact shape. ...


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Why is it that in one experiment, the surface tensions drops whereas in the other one it increases? The surface tension decreases in both cases Where is my mistake in tackling that problem? To form a long-lasting bubble you need lower surface tension and something that reduces the rate of evaporation. The soap provides both these. The hydrophobic ...


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I think the key is in the word 'behave'. The surface is not stretched (as this would indeed lead to larger surface area), but rather it behaves as such i.e. if you push into it, it will recoil to its original position as if it where a stretched membrane


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It looks to me as a capillary-gravity wave instability, caused by the relative motion of air with respect to the surface. Ripples appear on smooth fluids when a wind-like current blows over them, but will die quickly if it stops. The restoring force that allows them to propagate is surface tension. Capillary waves are common in nature, and are often ...


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The phenomenon you mention is called Noncoalescence, and there are many beautiful experimental examples of it (see for instance [1],[2]). Indeed, droplets of various liquids may float on the respective surfaces for extended periods of time prior to coalescence. The problem of explaining why this happens has been addressed by Klyuzhin et al. a few years ...


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To simplify, let's consider a weightless blob of water in the Space Station, not touching anything The water molecules all attract one another. Inside the water blob, they can approach freely and then move away, attracted by others. They move around inside the droplet. On the surface of the water blob, there is nothing outside to attract them, and only ...


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The (very small) air bubbles you see sticking on your hand when you immerse your hand in tap water, are of two types: 1- Bubbles which contain air outside the water. This air is trapped along your fingerprint lines when you insert your hand inside water. Typically, the lower the surface tension, the lower the probability and size of these bubbles. You can ...


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These bubbles are any gas that is "in" the water. I heard about this in the context of "not enough oxygen in water for fish". (Yes, your question is the opposite, but maybe you can find some hint searching in this context, "Limnology" is the physics of lakes etc.) I see two points you could use - or maybe both: de-gas the water Run the water through a low ...


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TL;DR a droplet intersects the stream, temporarily diverting it. The glass is not uniform due to surface contaminates like oil and dirt. This makes the binding energy between the water and the glass vary by location. A droplet that land on the glass with one edge on a high binding energy location and the opposite edge on the low binding energy location will ...



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