ATOMIC THEORY OF ELECTRONICS

Basics of Electronics:

When we speak about electronics, first few terms that strikes in our minds are CURRENT, VOLTAGE, ENERGY Etc., Every Electronic Engineer would say the famous definition of current “Flow of electrons is called as current” but very few gets deeper in to it and raises a question - how it is said that movement of electrons are referred to as current, and these few people gets success in engineering.

What is electronics?

                The branch of physics and technology concerned with the design of circuits using some electronic components with the behavior and movement of electrons in a semiconductor, conductor, vacuum, or gas.

            To understand more about the electronics we must learn the very basics of electrons like, from where the electron came from and some concepts behind the electrons.

ATOMIC STRUCTURE:

                All the materials are composed of very small particles called atoms. Large number of atoms makes a matter or substance. One single atom consists of central Nucleus of positive charge around which the small negatively charged particles called Electrons revolve in different paths or orbits.

Components of an Atom

1.   Nucleus: contains Protons and Neutrons

            Protons: They are the positively charged particles

            Neutrons: They have the equal mass of protons, but have no charge (Neutral)

Hence the Nucleus is positively charged in nature.

2.   Electrons: It is the outer part of the atom which revolves around the nucleus. Electrons have the negligible mass compared to the protons and neutrons. They have the same amount of charge as proton but with opposite polarity (Negative)

In an atomic structure number of protons is equal to the number of electrons.

The following video shows the visual of how the electrons revolve around the nucleus:

ENERGY OF AN ELECTRON:

            An electron moving around the nucleus possesses two types of energies, they are

1.    Kinetic energy – due to the motion

2.    Potential energy – due to the charge in the nucleus

Total energy of the electron is calculated by the sum of these two energies.

The energy of an electron increases with the distance between the nucleus and electron increases. Which means the electron in the second orbit will have higher energy than the electrons in the first orbit. From this we can infer that the electron at the outer most orbit have the highest energy. The electrons present in the outer most orbits are called as the valance electrons. The maximum number of valance electrons permitted in orbit is 8

This valance electron determines the chemical (solid or liquid or gas) and physical properties (conductor, insulator, semi conductor) of a material.

1.   When the number of valance electrons are less than 4 then the material is said to be a CONDUCTOR

2.   When the number of valance electrons are more than 4 then the material is said to be an INSULATOR

3.   When the number of valance electrons are exactly 4 then the materials are said to be a SEMI – CONDUCTOR

FREE ELECTRONS:

                Free electrons determine the conductivity of a material. The valance electrons which are very loosely attached to the nucleus are called as free electrons.

1.    A conductor has a large number of free electrons.  When a potential difference is applied these free electrons move towards the positive terminal constituting the electric current.

2.    An insulator has no free electrons hence; there is no possibility for electron flow.

3.    A semi conductor has very little number of free electrons, by the level of potential difference this can be used as neither conductor nor insulator as well. 

CONCLUSION:

            Hope you got a better idea on what is electronics. Yes! It is complete study of behavior of electron and the techniques behind controlling the electrons.