(i) Define the term coefficient of viscosity. Name the unit of viscosi

(i) Define the term coefficient of viscosity. Name the unit of viscosity coefficient in cgs system. (ii) Give the difference between boiling and evaporation.

Answer»

(i) Coefficient of Viscosity: It is defined as the force when velocity gradient \(\frac{du}{dz}\)and area of contact (A) both are unity.

F = \(\eta\)A\(\frac{du}{d\mathrm{x}}\)

F = \(\eta\) x 1 x 1 = \(\eta\)

Where F = Force

\(\eta\) = Coefficient of viscosity

In cgs system, the unit of coefficient of viscosity is poise or g cm^-1s^-1.

(ii) Difference between boiling and evaporation:

Boiling	Evaporation
The condition of free vapourization throughout the liquid is known as boiling.	The process by which molecules of liquids go into the gaseous state is known as evaporation.