The surface tension of a liquid is $5 \,N/m$. If a film is held on a ring of area $0.02 \,m^2$,its surface energy is about ........... $J$.

The amount of work done in blowing a soap bubble such that its diameter increases from $d$ to $D$ is ($T=$ surface tension of solution).

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:

The work done in blowing a soap bubble of $10\, cm$ radius is (Surface tension of the soap solution is $\frac{3}{100}\,N/m$).

If the work done in blowing a soap bubble of volume $V$ is $W$,then the work done in blowing a bubble of volume $2V$ from the same soap solution is:

$A$ water film is formed between two parallel wires of $10 \text{ cm}$ length. The distance of $0.5 \text{ cm}$ between the wires is increased by $1 \text{ mm}$. The work done in the process is (surface tension of water $= 72 \text{ mN/m}$).