Fundamental of electricity

 Fundamental of electricity

Electricity:

            Electricity is a form of energy, neither can be seen nor can be touched only felt in the form of electric shook. Electricity is 2 types:

1.      Static electricity (the electricity that does not move is called static electricity, example: comb attracting paper)

2.      Electric current (the Electricity in motion is called electric current, example: lighting lamp & running motor)

Atomic structure:

1.      Matter: Matter is defined as anything that has mass and occupies space.

2.      Molecule: molecule is the smallest particle of a substance or matter and that has the properties of the substance or matter.

3.      Atom: An atom is the smallest particle of substance or matter that forms a chemical element. An atom contains three types of sub-atomic particles called:-

a.       Electron: Electron is the negatively charged particle of an atom. It revolves around the nucleus. It takes important role in flow of electric current.

b.      Proton: proton is the positively charged particle an atom. It does not take part in during flow or transfer of electrical energy.

c.       Neutron: Neutron is the charge less particle of an atom. It is electrically neutral so, they are not too important to the electrical nature of atoms.

4.      Nucleus: Nucleus is the central part of the atom. It contains protons and neutrons.

5.      Energy shells: In an atom, electrons are arranged in shells around the nucleus in an orbit, that orbit is called “energy shell”. Those shells are named K, L, M, N (From inside to outside orbit). Electrons are distributed among the orbit K, L, M, N according to formula 2N² (where, N= no. of shell/orbit).

Note:

·         In an atom the number of protons is equal to the number of electrons.

·         Anion: when an atom gains an electron that becomes anion (due to maximum no. of electron).

·         Cation: when an atom looses an electron that becomes cation (due to maximum no. of proton).

·         Free electron: The outer shell of the atom is called the valence shell and its electrons are called valence electrons. The attracting force exerted by nucleus on the valence electrons is less. Therefore, valence electrons can be set free most easily. Whenever a valence electron is removed from its orbit it becomes a free electron.