Which graph represents the variation of surface tension with temperature over small temperature ranges for water?

The force required to take away a flat circular plate of radius $2 \ cm$ from the surface of water is $[$ Surface tension of water $= 70 \times 10^{-3} \ Nm^{-1}, \pi = \frac{22}{7} ]$

$A$ 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 ............ $N \, m^{-1}$

Describe a simple experiment for the measurement of the surface tension of a liquid.

The force required to take away a flat circular plate of radius $2 \, cm$ from the surface of water will be (the surface tension of water is $70 \, dyne/cm$).

The free surface of a liquid has a tendency to contract. This property is called ...... .