Q. The excess pressure inside a spherical drop of radius $r$ of a liquid of surface tension T is
A) Directly proportional to r and inversely proportional to T
B) Directly proportional to T and inversely proportional to r
C) Directly proportional to the product of T and r
D) Inversely proportional to the product of T and r
Explanation
(a) The excess pressure inside a liquid drop is
$\mathrm{\Delta}p = \frac{2T}{r}$
$or\ \ \ \ \mathrm{\Delta}p \propto \frac{T}{r}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ $
[image:10_image74.emf]
The excess pressure inside a liquid drop is directly proportional to surface tension (T ) and inversely proportional to radius (r).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.