$A$ paper disc of radius $R$ from which a circular hole of radius $r$ is cut out,is floating in a liquid of surface tension $T$. The force on the disc due to surface tension will be

$A$ rectangular film of liquid is extended from $(4 \, cm \times 2 \, cm)$ to $(5 \, cm \times 4 \, cm).$ If the work done is $3 \times 10^{-4} \, J,$ the value of the surface tension of the liquid is ............ $N \, m^{-1}$

$A$ thin metal wire of density $\rho$ floats on the water surface horizontally. If it is $\text{NOT}$ to sink in water,then the maximum radius of the wire is proportional to $(T = \text{surface tension of water}, g = \text{gravitational acceleration})$.

Soap helps in cleaning clothes,because

$A$ beaker of radius $15\, cm$ is filled with a liquid of surface tension $0.075\, N/m$. The force across an imaginary diameter on the surface of the liquid is:

Why is the surface tension of antiseptics kept low? Explain.