Question

Suppose there is an air bubble of radius $\frac{R}{2}$ inside the air cavity of radius R inside a water drop of radius 3R as shown in figure. The ratio of gauge pressure at point C to gauge pressure at point B is :

• A. 4
• B. 8
• C. 12
• D. 16

Answer 1

Answer: (D)

16

Pressure at point $B=P_0+\frac{2T}{3R}⟹P_B-P_0=\frac{2T}{3R}$

Pressure at point $C=P_0+\frac{2T}{3R}+\frac{2T}{R}+\frac{4T}{R/2}$

$⟹P_C-P_0=\frac{32T}{3R}$

Ration of $P_C-P_0\&P_B-P_0=16$