Question

The excess pressure inside a soap bubble A is twice that in another soap bubble B. The ratio of volumes of A and B is

• A. 1:02
• B. 1:04
• C. 1:08
• D. 1:16

Answer 1

Answer: (C)

1:08

Answer 2

Excess pressure inside the bubble is $p=\frac{4T}{r}$ Here, ${{p}_{A}}=2{{p}_{B}}$ $\frac{{{p}_{A}}}{{{p}_{B}}}=\frac{{{r}_{B}}}{{{r}_{A}}}$ So, radius of bubble $B$ is ${{r}_{B}}=2$ Ratio of volumes $\frac{{{V}_{A}}}{{{V}_{B}}}={{\left( \frac{{{r}_{A}}}{{{r}_{B}}} \right)}^{3}}={{\left( \frac{1}{2} \right)}^{3}}$ $\frac{{{V}_{A}}}{{{V}_{B}}}=\frac{1}{8}$