Question: Work done in increasing the size of a soap bubble from a radius of $3 \mathrm{~cm}$ to $5 \mathrm{~cm}$ is nearly (Surface tension of soap solution $=0.03 \mathrm{Nm}^{-1}$ ) :-
$2 \pi \mathrm{mJ}$
$0.4 \pi \mathrm{mJ}$
$4 \pi \mathrm{mJ}$
$0.2 \pi \mathrm{mJ}$
Correct Option: , 2
Solution:
