The property utilized in the manufacture of lead shots is

When water is filled carefully in a glass,one can fill it to a height $h$ above the rim of the glass due to the surface tension of water. To calculate $h$ just before water starts flowing,model the shape of the water above the rim as a disc of thickness $h$ having semicircular edges,as shown schematically in the figure. When the pressure of water at the bottom of this disc exceeds what can be withstood due to the surface tension,the water surface breaks near the rim and water starts flowing from there. If the density of water,its surface tension and the acceleration due to gravity are $10^3 \ kg \ m^{-3}$,$0.07 \ N \ m^{-1}$ and $10 \ m \ s^{-2}$,respectively,the value of $h$ (in $mm$) is:

The property of surface tension is obtained in

It is better to wash clothes in hot water than in cold water. Explain.

Two pieces of glass plates placed one upon the other with a little water in between them cannot be separated easily because of:

An iron needle slowly placed on the surface of water floats because