Electric Charge

Atoms

To understand electricity, we need to start with understanding atoms. Atoms are the smallest unit of matter. Everything around us, animate and inanimate objects, visible and invisible matter (solids, liquids, and gases), is composed of atoms. An atom itself is made up of three even smaller particles referred to as subatomic particles: protons, neutrons, and electrons.

All subatomic particles have a physical property known as electric charge. The electric charge can be positive, negative, or neutral. Protons carry a positive electric charge, electrons carry a negative electric charge, and neutrons have a neutral charge, they are neither positive nor negative. Like charges repel each other and unlike charges attract each other.

The center of an atom is called the nucleus, which is made up of protons and neutrons. The electrons move in orbits (referred to as shells) around the nucleus. Since they carry a negative charge, they are bound to the nucleus by an electrical force of attraction with the protons, which carry a positive charge.

Electrons move in multiple shells at varying distances from the nucleus. The electrons in the shells closest to the nucleus have a strong force of attraction to the protons, while the electrons in the outer ones have a lesser force of attraction. The electrons in the outermost orbit can have a weak enough force of attraction that they can be pushed out of their shells by an external force and jump from one atom to another. These jumps result in a flow of electrons and give us what we know as electricity.

Under certain circumstances, when two objects come into contact with each other, electrons may move from one object to another, which leaves an excess positive charge on one material, and an equal excess negative charge on the other one. When the materials are separated, they retain this charge imbalance.

Subsequently, if you touch the object with the excess positive charge, it seeks to discharge the excess charge through your body to the earth, giving you a brief and very minor jolt, which is referred to as static electricity.

Magnetism

The spinning of the electrons around the nucleus of an atom creates a small magnetic field. In most objects, the electrons spin in random directions, and their magnetic forces cancel each other out. In some objects, the electrons spin in the same direction. This arrangement and movement of electrons create a magnetic force, which creates a magnetic field around the object. Such objects are known as magnets.

Generating Electricity

There are several methods to convert other forms of energy into electrical energy. The oldest and still the most widely used is by rotating a magnet inside a coil of wire or rotating a coil of wire around a magnet, which causes the electrons in the wire to flow and create an electrical current. This approach converts kinetic energy (the energy of motion) into electrical energy, and the machines that do this are known as generators.

The mechanical rotation of the magnets can be achieved by placing them in the path of flowing water or air or by using heat energy to generate steam which can then force the rotation.

The other options include the conversion of chemical or light energy to electricity using the effect of chemical reactions. It is how electricity is generated in batteries.