The Pressure Excess Notion: Why is the Formula Multiplied by 2?

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The discussion centers on the pressure excess formula for droplets and bubbles, highlighting the difference in surface tension effects. For a droplet, the pressure excess is calculated as p=2T/r due to the presence of only one surface. In contrast, a bubble has two surfaces (inside and outside), leading to the formula p=4T/r. The reasoning is that as the radius increases, the surface area of a droplet increases only once, while a bubble's surface area increases twice. This distinction clarifies why the formulas differ by a factor of two.
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in the surface tension about the pressure excess notion i have problem: why for a full dropplet of water the formula is p=2T/r whereas for a bubble p=4T/r. Why does it be multiplied by 2.
 
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In a filled drop there is only a surface. In a bubble there is also the internal surface. When you increase the radius, in the first cas,e only a surface increases. In the second, two surfaces increase.
 
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