What is mechanics ?
The branch of science that deals with the study of motion of body,its causes and effects.
The importance of mechanics
It is the oldest of the physical sciences,is the study of the motion of objects.The calculation of the path of a baseball or of a space probe sent to Mars is among its problems,as is the analysis of the tracks of elementary particles formed collisions in our largest accelerators.
What are three types of mechanics?
- Quantum Mechanics
- classical Mechanics
- Fluid Mechanics
“It is the study about very tiny things.”In the early part of the twentieth century,many experimental and theoretical problems remained unresolved.Attempts to explain the behavior of matter on the atomic level with the laws of classical physics were not successful.Phenomenon such as black body radiation,the photoelectric effect,the emission of sharp spectral lines by atoms in a gas discharge tube,and in variance of speed of light,could not be understood within the framework of classical physics.To explain these observations a revolutionary framework of explanation was necessary which we call modern physics.Its two most significant features are relativity and quantum theory.The observations on objects moving very fast,approaching the speed of light,are well explained by the special theory of relativity.Quantum theory has been able to explain the behavior of electromagnetic radiation as discrete packets of energy and the particles on a very small scale are dominated by wave properties.
Classical physics is still valid in ordinary processes of everyday life.But to explain the behavior of tiny or very fast moving particles ,we have to use the above mentioned theories.In order to understand the current voltage characteristics,we need some knowledge of the electron behavior in a crystal when the electron is subjected to various potential functions.
The motion of large objects,such as planets and satellites,can be predicted to a high degree of accuracy using classical theoretical physics based on Newtons laws of motion.But certain experimental results,involving electrons and high frequency electromagnetic waves ,appear to be inconsistent with classical physics.However these experimental results can be predicted by the principles of quantum mechanics.The Quantum mechanical wave theory is basis for the theory of semiconductor materials whose electrical properties are directly related to the behavior of electrons in the crystal lattice.