Question

If a film of area $0.5m^2$ is formed of a liquid having surface tension 0.2 N/m, then potential energy of the film will be

• A. $5\times {10}^{-2}$
• B. $2\times {10}^{-1}$
• C. $3\times {10}^{-2}$
• D. None of these

Answer 1

The correct option is D None of these

$E=\frac{n\pi }{A}T=\frac{E}{A},E=T\Delta A$

$E=0.2\times 0.5$

$E=1\times {10}^{-1}$

$\therefore$ Option $D$ is correct.