Biripali

                            Solids:-    Sol ids : The solids are the forms of matter in which atoms ands molecules are strongly bound and maintain definite volume and sharp unless changes by applying external forces. Solid state physics: - The solid state physics is the study of the physical properties of the atomic/molecular matter in the solids state. These physical properties include crystal structure, bonding,thermal, electric and magnetic properties. Classification of solids:         Solids are classified into two categories; (1) crystalline solids (2) Amorphous solids. (1) crystalline solid :-        The crystalline solids are defined as an ordered periodic arrangements of atoms, molecules or ions . Properties of crystalline solids:- • The internal arrangements of atoms,ions or molecules of crystalline solids is in a definite order. • The crystalline solids have ...

Post ulates of kinetics theory :-        Suppose a container with volume v contain a very large numbers N of identical molecules,each with mass m. Then, the kinetics theory postulates the following- (1) The molecules behave a point particles that are small compared to the size of the container and to the average distance between molecules. (2) The molecules are in constant motion. Each molecules collides occasionally with a wall of the container. These collisions are perfectly elastic. (3) There is no force of attraction among the gas molecules and between the gas molecules and walls of the container. (4) The container walls are right and infinitely massive and do not move. (5) The molecules obey Newton's law of motion. (6) The time of collision is much less than the averaged time between two successive collision. Meaning of elastic collisions:- If a molecule with velocity u strikes a wall align along y-axis, then the collision is elastic if • velocity componen...