The electricity is a physical property of matter. It consists of that negative or positive interaction between the protons and the electrons of matter. The term refers to the amber color, for the versatile and luminous color it presented. However, the term was first introduced into scientific society by the English scientist William Gilbert (1544-1603) in the 16th century to describe the phenomenon of energy interaction between particles.
What is electricity
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Physical electricity is understood to be the phenomena that are manifested by the presence of electric charges present in bodies, since they are made up of molecules and atoms, whose interaction of their subparticles generates electrical impulses. The positive and negative charges on atoms is static electricity, while the movement of electrons and their release from the atoms produce electrical currents.
This is part of electromagnetism, which, with gravity and the weak nuclear force and the strong nuclear force, forms the fundamental interactions of nature.
Its etymology comes from the Latin electrum, also from the Greek élektron, which means “amber”. The Greek philosopher Thales of Miletus (624-546 BC) observed how friction magnetized amber with static electricity, and centuries later the scientist Charles François de Cisternay du Fay (1698-1739), noticed how the positive charges of electricity they were revealed when glass was rubbed, and, in turn, negatives were shown when resins, such as amber, were rubbed.
The flow of energy from moving or static charges is what is called electricity, or the transfer of electrons from one atom to another, and the resulting electrical force is measured in volts or watts, a term used in electricity in English, and It was named after the inventor of the steam engine James Watt (1736-1819).
However, it is possible to find electricity in nature, as in the case of atmospheric events, bioelectricity (electricity present in some animals) and the magnetosphere.
One of the best known cases of animals that produce electricity is that of the electric eel, which has in its body electrocytes (an organ of this animal that generates electric fields), which are found throughout its body, functioning in a similar way to neurons and can generate up to 500 volt discharges.
As there is a diversity of elements, their atoms are different; that is why some materials are carriers of electricity and other insulators. The best conductors are metals, since they have few electrons in their atoms, so it is not necessary more energy for these sub-atomic molecules to jump from one atom to another.
Electricity characteristics
According to its dynamics, origin, performance and phenomena that it produces, it has characteristics that make it stand out. Among the main ones are:
- Cumulative. There are devices with the ability to store electricity in chemical substances inside accumulators, which allow it to be retained for later use (batteries).
- Its way of obtaining. In the case of batteries or cells, it is obtained chemically; also by electromagnetic induction when moving a conductor in a magnetic field, like alternators; and from light, when certain types of metals release electrons when sunlight falls on them (solar panels).
- Its effects. These can be physical, mechanical or kinetic, thermal, chemical, magnetic and luminous.
- Its manifestations. They can be in the form of lightning, static electricity, current flows, among others.
- Dangerousness. By generating heat, it can cause severe burns and in cases of stronger exposure, death.
- Resistivity and conductivity. It is the opposition of some types of matter in front of its passage and the easy flow of it, respectively.
Types of electricity
There are several types of electricity, the most important are:
Static
Static arises from excess electrical charge, which accumulates in a conductive or insulating material.
It is known that atoms are composed of a certain number of protons (positive charge) in their nucleus and the same number of electrons (negative charge) orbiting around it, which makes said atom electrically neutral or in equilibrium; but when friction is generated between two bodies or substances, charges may be generated on said objects.
This is because the electrons of both materials will come into contact, producing an imbalance in the charges of the atoms, leading to static. It is so called because it is generated in atoms that are at rest and its charge does not move but remains stationary. An example of this is when we pass a brush through the hair and some are lifted by the static of the friction between the material of the same and the hair. Artifacts like printers use static to reveal the toner or ink on the paper.
Dynamic
This type is produced by a load that is in motion, or the flow of it. To do this, you need an electrical source (which can be chemical, such as a battery, or electromechanical, such as a dynamo) that makes electrons flow through a conductive material through which these electrical charges can circulate.
In it, electrons move from one atom to the next and so on. This circulation is known as electric current. An example of this type of electricity is electrical outlets, which are a dynamic source of electricity for appliances and other appliances that require electricity.
It is important to highlight the existence of other types of electricity, among which are:
- Basic: This type is the one that refers to the attraction of positive and negative charges, where the objects will be charged. It is generated from two poles, which must not necessarily touch but attract each other. This type of electricity is found in everyday objects.
- Behavioral: It is considered as part of the dynamics, since it is the one that is transported by means of conductors, which is why it keeps moving through the circuits. There are various conductors, such as metals (especially copper), aluminum, gold, carbon, among others.
- Electromagnetic: It is generated by a magnetic field, which can be stored and emitted as radiation, so it is recommended not to expose yourself to this type of field for a long time. Physicist Hans Christian Ørsted (1777-1851) discovered the relationship between magnetism and electricity, observing that electric current creates a magnetic field.
Among the applications of this type of electricity stands out in medicine, for example, for X-ray machines or to perform magnetic resonance imaging.
- Industrial: This is what must be generated for the large machinery used in the mass production of products, which require large amounts of energy because they are of high power.
It was developed after science proved that natural energy resources such as lightning, could be channeled and used by man, becoming a powerful source of electrical energy, which allowed meeting the needs of industry.
Electrical manifestations
Electric charge
It is a property that some subatomic particles (electrons, neutrons and protons) have to attract and repel each other, as well as it defines their electromagnetic interaction. This is produced in the atoms, which will transfer it to the molecules of a different body, or through a conductive material. It also refers to the ability of a particle to exchange photons (particles of light or electromagnetic energy).
This is present, for example, in static electricity, which is a charge stationary in a body. Also, a charge gives rise to the electromagnetic force, since it produces force on others. Charges may be negative and others positive, and charges of the same type will be repelled, while opposite charges will attract.
The charges are measured through the unit coulomb or coulomb and is represented by the letter C, and it means the amount of charge that passes through a section of some conductor in a period of one second. Both matter and antimatter have equal and opposite charges to their corresponding particle.
Electric current
This is the flow of electric charge through a material, produced by the movement of electrons or some other type of charge. It will produce a magnetic field, one of the electrical phenomena that can be exploited, in this case by an electromagnet.
The materials through which this flow will circulate can be solid, liquid or gaseous. In solid materials, electrons move; ions (atoms or molecules that are not electrically neutral) move in liquids; and the gaseous ones, can be both electrons and ions.
The amount of current charge per unit of time is known as the intensity of electric current, which is symbolized by the letter I and is stated as coulombs per second or ampere.
The electric current can be:
- Continuous or direct, which are those flows of charges that circulate in a constant path, it is not interrupted by any vacuum period, because it is in only one direction.
- Alterna, which is the one that moves in two directions, modifies its route and its intensity.
- Triphasic, which is the grouping of three alternating currents with the same amplitude, frequency and effective value (concept used to study periodic waves), presenting a difference of 120º between phase and phase.
electric field
It is an electromagnetic field that has been generated by an electrical charge (even when it is not moving) and that affects the charges that surround it or are in it. The fields are not measurable, but the charges that are placed on them can be observed.
An electric field is a physical space where the electric charges of the different bodies interact, and the concentration of the intensity of an electric force is defined. In this region the properties have been modified by the presence of a charge.
Electric potential
It refers to the capacity of an electric body, or the energy it requires to move a load or perform work and is measured in volts. This concept is related to that of potential difference, which is defined as the energy needed to move a charge from one point to another.
This can only be defined in a limited region of space for a static field, since for moving charges, the Liénard-Wiechert potentials are used (they describe the electromagnetic fields of a distribution of moving charges).
Electromagnetism
This refers to the magnetic fields that are generated due to the electrical charges that are in motion, and that produce the attraction or repulsion towards the materials that are within these fields, which can generate electrical current.
Electrical circuits
It refers to the connection of at least two electrical components, so that the electrical charge can flow in a closed path for some specific purpose. These are made up of elements such as components, nodes, branches, meshes, sources, and conductors.
There are circuits with a receiver, as in the case of bulbs or bells; series circuits, like Christmas lights; circuits in parallel, as in the case of lights that turn on with the same switch simultaneously; mixed circuits (they combine series and parallel); and switched, which are those that allow, for example, to turn on one or more lights from more than one different point.
History of electricity
The antecedents of electricity go back to ancient times, even almost three thousand years before Christ, where the human being observed certain electrical phenomena in nature, despite not knowing how they were produced or their dynamics. Likewise, they were witnesses of certain magnetic phenomena produced by some types of materials obtained in nature, such as magnetite, or the presence of it in animals.
In approximately 2,750 BC, the Egyptian civilization wrote about the electric fish found in the Nile River, referring to them as the protectors of the other fauna in it. Around 600 BC, Thales of Miletus was the first person to discover that amber acquired electrical and magnetic properties when rubbed with a specific material. But electricity as a science dates back to the seventeenth and eighteenth centuries, in the middle of the scientific revolution, when the appearance of this field of study was the perfect context for the beginning of the industrial revolution, and its expansion throughout the modern world that was rising, it was crucial for the development of humanity.
Prior to this, in the 16th century, the philosopher and physician William Gilbert (1544-1603) made important contributions to the study of the electrical phenomenon, paying special attention to electricity and magnetism. The terms "electricity" and "electric" first appear in 1646 in the work of the Englishman Thomas Browne (1605-1682). The units of measurement for the different electrical phenomena emerged later thanks to multiple contributions from intellectuals in physics.
The scientist, politician and inventor Benjamin Franklin (1706-1790), in 1752 managed to channel the electrical power contained in a lightning bolt through a kite, which led to the invention of the lightning rod; a device that serves to conduct electricity from lightning to the ground. Later, the Italian physicist Alessandro Volta (1745-1827), invented the voltage battery in 1800 that allowed to store energy, taking advantage of the use of electricity generated by chemical reactions; and in 1831 the physicist Michael Faraday (1791-1867), developed the first electrical generator, which allowed to send electrical current continuously.
The first stage of the industrial revolution did not involve electricity for its development, as it made use of energy generated by steam. Already towards the second industrial revolution in the 19th century, electricity and oil were used to generate energy, which allowed the scientist Thomas Alva Edison (1847-1931) to light the first filament light bulb in 1879.
At the end of the 19th century and the beginning of the 20th century, Edison, defender of direct current, and the inventor and engineer Nikola Tesla (1856-1943), father of alternating current, disputed the future of electricity.
Direct current was popularized in the United States for domestic and industrial use; however, it was soon discovered that it was inefficient over long distances and when higher voltage was required, and emitted enormous amounts of heat.
Tesla developed experiments that led to discovering alternative ways to transport electrical energy more efficiently, which resulted in the discovery of alternating current.
George Westinghouse (1846-1914), an American businessman, supported and bought Tesla's invention, which eventually won the battle for electricity as a cheaper type of current with less energy loss.
Importance of electricity
Its importance is vital for modern life, being one of the fundamental pillars of today's society, since basically everything that human beings use involves electricity to function: electrical appliances, machinery, communications, some forms of transport, production of goods and services, for the area of medicine, science, among other areas.
It can be created by man or harnessed directly from nature. Man-made electricity is created by turbines, condensers, and machinery that rely on the force of nature to function, such as dams, which use the force of large amounts of water to generate the current that supplies large cities.
The planet Earth is also capable of generating electricity, those rays, flashes and lightning that we see in the sky in the middle of a storm are electrical discharges generated by the collision of huge clusters of matter and energy. This is called natural electric current and it can be used by man with lightning rods and super resistant conductors capable of absorbing the impact of a discharge of such magnitude.
10 examples of the use of electricity
Electricity has multiple uses in human activities. Among the most prominent examples are:
- In vehicles with automotive electricity, which circulates through circuits that reach parts of it and that require electricity to function, such as lights, the horn, the engine, among others, and is generated from a battery.
- For lighting, that is, for switching on domestic, public and industrial lighting.
- For the ignition of electrical appliances and electronics.
- To generate heat in temperate climates, such as through heating.
- For transport, such as airplanes, since they need electricity to take off.
- For the medical field, used in devices used for analysis and studies.
- In industry, which requires large amounts of electrical charge to manufacture consumer products.
- To generate movement through motors that drive electrical power, converting electrical energy into mechanical energy.
- For communications, used in devices such as repeater antennas, transmitters, among others.
- For the transport and control of fluids, such as water, through solenoid valves that help to moderate the flow.
