Q. The excess pressure inside one soap bubble is three times that inside a second soap bubble, then the ratio of their surface areas is
A) 1:9
B) 1:3
C) 3:1
D) 1:27
Explanation
(a) Accordingly
$\frac{4T}{r_{1}} = 3 \times \frac{4T}{r_{2}}\ \ \ \ \ \ \Longrightarrow \ \ \ \ \frac{r_{1}}{r_{2}} = \frac{1}{3}$
Ratio of surface areas
$\frac{A_{1}}{A_{2}} = \frac{{4\pi r}_{1}^{2}}{{4\pi r}_{2}^{2}} = \frac{1}{9}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.