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Grade 12General Physics

Excess pressure inside a liquid drop is given by .?

Profile image of sudhanshu
12 Years agoGrade 12
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1 Answer

Profile image of Apoorva Arora
11 Years ago
237-857_surtension.gif

It is because of surface tension that pressure of a liquid increases within a bubble. Consider the free-body diagram of a bubble as shown in Fig.1.8. If the force due to surface tension at the edge is balanced by the pressure force inside the bubble, we have
2\pi R\sigma =p\pi R^{2}
so,
p=\frac{2\sigma }{R}
where p is the pressure difference between inside the drop and that outside. In addition the pressure inside the bubble is greater than that outside.