How Does Electricity Works

Definition of Electricity

Atom in Electricity

Electricity is the flow of electrons from atom to atom in a conductor. To understand about electricity, let us study from the smallest part first, namely the atom. An atom has particles called electrons located in their orbits around protons.

The simplest atom is an atom of Hydrogen (Water Atom), which is an atom that has only one electron orbiting one proton. While the most complicated atoms are atoms of uranium. This atom has 92 electrons surrounding a proton nucleus. All objects have their own atomic structure.

Copper has 29 protons, the electrons are scattered in 4 orbital rows, while the outermost row contains only one electron. This is what makes it a good conductor of electricity. Any material that has an atomic structure of fewer than 4 electrons in the outermost orbital line will have good electrical conductivity. 

Whereas a material that has an atomic structure of more than 4 electrons in its outermost orbital line will make it an isolator (not a conductor).

The matrial that has only a few electrons in its outermost orbital line, causes electrons to move more easily from their orbits with lower voltages. This will cause the flow of electrons from atom to atom.

Repel Each Other

The picture above shows the electron transfer based on the experiment, when a rubber rod is rubbed with a wool cloth, the electrons will move and collect on the rubber rod. Thus, the wool will become electron-deficient, while the rubber will have an excess of electrons and make it negatively charged.

And then, the touch that comes from the rubber rod to the ball will cause excessive electron transfer to the ball, because the ball has the same charge as the rubber rod.

If we try to bring the rubber rod closer to the ball, the ball will move away from the rubber rod as shown in the picture. In other words, objects with the same charge will repel. In the experiment, both objects were negatively charged, and if both were positively charged, the same thing would happen.

Attract Each Other

What will happen if we bring a negatively charged rod closer to a positively charged ball?

The picture above shows that the ball will move closer to the rod and will be attracted by it (same as if a positively charged rod will attract a negatively charged ball). In other words, objects that have unequal charges will attract each other.

Electron Flow in a Conductor

The picture above is a copper conductor when it has a negative charge at one end and a positive charge at the other.

Copper has millions of electrons. It is shown that only a few atoms are represented by one electron in their outer orbit. If electrons are attracted to a positively charged atom, electrons leave the atom. This atom turns into a positively charged (+) because it lacks electrons, then the electrons in the previous atom move to the positively charged atom, and so on. The result is the movement of electrons from the ends of the negatively charged copper to the positively charged copper, which is called electron flow.

Based on the description above, electricity is the flow of electrons from atom to atom in a conductor.

Conductivity Material

• Conductor - A conductor is a material in which there are many free electrons that are easy to move. The attraction between the electrons in the outermost orbit and the nucleus is so small that even at normal temperatures one or more electrons are released from the atom. These free electrons move randomly in the space between the atoms. This movement of electrons is called diffusion. Examples of conductors: copper, iron, silver, aluminum, and some other metals.
• Semi-Conductor - A semiconductor is a material that cannot be classified as a conductor, nor can it be classified as an insulator. In this material, there are only one or two atoms that have lost electrons from about one hundred million atoms that exist. An example of a semiconductor: Germanium. 
• Insulator - An insulator is a material that cannot conduct electricity. In an insulator, all electrons are bonded to the atoms and there are no electrons that are free. These types of materials are classified as non-conductors or insulators. Examples of insulators: rubber, plastic, paper, wood, mica, and the like.

Please, for those who are interested, also read the article about Magnet