It is one of the characteristic properties of liquids. Viscosity is a measure of resistance to flow which arises due to the internal friction between layers of fluids as they slip. past one another while liquid flows.
Strong intermolecular forces between molecules hold them together and resist movement of layers past one another.
When a liquid flows over a fixed surface, the layer of molecules on the immediate contact of surface is stationary.
The velocity it's dimensions are J m-2. Surface tension is defined as the force acting per unit length perpendicular to the line drawn on the surface of liquid. It is dimensions of kg-2 and in SI unit it is expressed as Nm-1. The lowest energy state of the liquid will be when surface area is minimum.
Spherical shape satisfied this condition, that is why mercury drops are spherical in shape. This is the reason that sharp glass edges are heated for making them smooth.
This is called fire 🔥 polishing of glass. Because of surface tension
Luquids wet the because of surface tension. Luquids wet the things because they spread across their surfaces as thin film. Most soil grains are pulled together because surface area of thin film of water is reduced. It is surface of a liquid.
On flat surface, droplets are slightly flattened by the effect of gravity; but in the gravity free environment drops are perfectly sperical.
The magnitude of surface tension of a liquid depends on the attractive forces between the molecules.When the attractive forces are large, the surface tension is tension is large. Increase in temperature increases the kninetc energy of the molecules and decrease, so surface tension decreases as the temperature is raised.
