We see that an object attracts another object in a special condition or becomes charged that is electricity produced in the object. Their charge remains static in the place of its production. So it is called static electricity. Now let us see what we mean by being charged.
We know that each matter is consisted of small particles. The atom of every matter consists of electrons and which revolves around the nucleus. In the nucleus there are two type of particles-proton and neutron. The fundamental and special property of primary particles (electron and proton) of which the matter consist of is electrical property, which is detained by charge. The charges of electrons are negative and the charges of protons are considered to be positive. Neutron is electrically neutral that is it has no charge. The amount of charge in a proton is equal to the charge of an electron. Naturally an atom has an equal number of protons and electrons. As a result in the atom whole atom there is no electrical property to be detected. The number of electrons and protons in different matters is different.
As long as the number of electron and proton are equal in any atom, it is electrically neutral. But if their number is not equal in any atom, then the atom will be charged. If the number of electron decreases, the number of proton increases. This situation is said to be charged positively. Again, if these scattered electrons are joined with any atom, the number of its electron increases, as a result it is charged negatively. The shortage or excess of electrons in any atom is considered to be charged.
The substances through which electricity or electric charge can pass easily are called conductors, e.g. metal, soil, human body etc. Generally the metals are good conductors. Copper, silver, aluminum etc are good conductors. On the other hand the substances through which electricity or electric charge cannot pass easily are called nonconductors or insulator, such as wood, paper, glass etc.
