Question

The surface tension of soap solution is $0.03\, N/m$. The work done in blowing to form a soap bubble of surface area $40 \, cm^2, (in\, J)$ is

• A. $ 1.2 \times 10^{-4} $
• B. $ 2.4 \times 10^{-4} $
• C. $ 12 \times 10^{-4} $
• D. $ 24 \times 10^{-4} $

Answer 1

Answer: (B)

In case of soap bubble
$W = T \times 2 \times \Delta A$
$ = 0.03 \times 2 \times 40 \times 10^{-4}$
$ = 2.4 \times 10^{-4} \, J $