Electricity

Electricity

Electricity is the flow of electrical power or charge. It is a secondary energy source which means that we get it from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power, and other natural sources, which are called primary sources. The energy sources we use to make electricity can be renewable or non-renewable, but electricity itself is neither renewable nor non-renewable.

Electricity comes from many sources. Such as coal power plants, nuclear power plants, and renewable energy sources such as wind, solar and hydroelectric dams.

In general usage, the word “electricity” is adequate to refer to a number of physical effects, however is better to use more precise terms as:

electric charge
Electric charge is a property of some particles, which determines their electromagnetic interactions. The electrically charged matter is influenced by and produces electromagnetic fields.

electric current
It is a movement or flow of electrically charged particles, typically measured in amperes.

electromagnetism
It is an interaction between the magnetic field and the presence and motion of an electric charge.

electric field
Is an influence produced by an electric charge on other charges in its vicinity.

electric circuit
Electricity travels in closed loops, or circuits (from the word circle).

Electric potential is the capacity of an electric field to do work on an electric charge, typically measured in volts.

Atom

Everything in the universe is made of atoms — stars, trees, animals…. The human body is made of atoms. Air and water are, too. Atoms are like building blocks. They are so small that millions of them would fit on the head of a pin.

The center of an atom is called the nucleus. It is made of particles called protons and neutrons. The protons and neutrons are very small, but electrons are much, much smaller. Electrons spin around the nucleus in shells a great distance from the nucleus.

The atom looks like a ball surrounded by invisible bubbles. The electrons are on the surface of the bubbles, constantly spinning and moving to stay as far away from each other as possible. Electrons are held in their shells by an electrical force.

The protons and electrons of an atom are attracted to each other. Protons have a positive charge (+) and electrons have a negative charge (-). The positive charge of the protons is equal to the negative charge of the electrons. Opposite charges attract each other. When an atom is in balance, it has an equal number of protons and electrons. The neutrons carry no charge and their number can vary.

The number of protons in an atom determines the kind of atom or element, it is.

Electrons usually remain a constant distance from the nucleus in precise shells. The shell closest to the nucleus can hold two electrons. The next shell can hold up to eight. The outer shell can hold even more. Some atoms with many protons can have as many as seven shells with electrons in them.

The electrons in the shells closest to the nucleus have a strong force of attraction to the protons.

Sometimes, the electrons in the outermost shells do not. These electrons can be pushed out of their orbits. Applying a force can make them move from one atom to another. These moving electrons are electricity.