# Find the excess pressure inside a liquid drop?

Apoorva Arora IIT Roorkee
8 years ago
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. If the force due to surface tension at the edge is balanced by the pressure force inside the bubble, we have
$2\pi R\sigma =p\pi R^{2}$
i.e
$P=\frac{2\sigma }{R}$
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.
Thanks and Regards
Apoorva Arora
IIT Roorkee