Question

What should be the pressure inside a small air bubble of $0.2mm$ diameter situated just below the surface of water.(Surface tension of water$=0.072N/m)$

• A. $1.44\times {10}^{2}Pa$
• B. $1.44\times {10}^{3}Pa$
• C. $1.44\times {10}^{4}Pa$
• D. $1.44\times {10}^{5}Pa$

Answer 1

Answer: (B)

$1.44\times {10}^{3}Pa$

$\text{weknow that}$

$P=\frac{2T}{r}$

$\Rightarrow \frac{2\times 0.072}{0.1\times {10}^{-3}}$

$=1440\text{pa.}$

$=1.44\times {10}^{3}Pa\text{.}$

$\text{Answerl-(B)}$