The concept of electric current is present in the world of nature and everyday life through all kinds of devices and cellular processes. If we think about the various electrical devices, they work due to the difference in potential facilitated by an electrical company . Just as there are storms, lightning and winds, their production also depends on electrical current. The same happens with the nerve impulses in our body.
The general idea of electric current
Electric current can be defined as the flux of electric charge per unit of time that passes through a given material or conductor. Generally, in this type of movement, electrons pass through a cable. We must know that the electron is a subatomic particle that has a negative electrical charge due to the physical law of attraction and repulsion, so any electron is attracted to a proton with an equivalent positive charge. In this way, the attraction takes place through the opposition of signs and the repulsion that starts when two charges of the same sign repel each other. The scientists observed that the positive charges never move because of its mass, because only electrons are those who in reality keep moving because it’s faster than protons.
If at one end or pole of a conductive material there is an excess of electrons and at the other pole there is an excess of protons, the electrons tend to move through the conductive material from the negative to the positive pole. This circulation of electrons through a certain conductive material is properly the electric current.
The electric current is expressed in Coulomb/seconds and its unit is called ampere. So when a current flows through a conductor it generates a magnetic field.
Electric current can be of two types and depend on its temporary variation
If the variation is constant over time, it is a direct or direct current, but if it varies over time, it is called an alternating current. In any case, the electrical current is measured by an instrument known as an ammeter, which is connected to a conductor in order to obtain the ampere value of the circulating current.
Electricity and Ohm’s Law
The idea of electric current presupposes the existence of electricity . To explain how it works, the nineteenth-century German physicist, who has the surname Ohm, discovered the law that governs electricity: Ohm’s law . According to this law, voltage, current and resistance are related in such a way that the flow of electric current through a closed circuit is proportional to the applied voltage and, in parallel, inversely and proportional to the resistance of the connected load.