Question

The work done in blowing a soap bubble of surface tension $0.06 ??Nm^{-1}$ from $2 \,cm$ radius to $5 \,cm$ radius is.

• A. 0.004168 J
• B. 0.003168 J
• C. 0.003158 J
• D. 0.004568 J

Answer 1

Answer: (B)

0.003168 J

Answer 2

$\Delta W = S \times\Delta A$ $= 0.06 \times4\pi\left(r^{2}_{2} - r^{2}_{1}\right)$ $= 0.003168 \,J$