The first discoveries related to the work of electricity began in the 7th century BC. The philosopher of Ancient Greece Thales of Miletsky revealed that when amber rubbed against wool, it was subsequently capable of attracting lightweight objects. From Greek "electricity" is translated as "amber". In 1820 André-Marie Ampere established the direct current law. In the future, the magnitude of the current strength, or what the electric current is measured in, began to be denoted in amperes.
Content
- The meaning of the term
- Basic measurement quantities
- Electrical safety engineering
- Application of electric current
The meaning of the term
The concept of electric current can be found in any physics textbook. Electric current Is an ordered movement of electrically charged particles in a direction. To understand the common man in the street, what constitutes an electric current, you should use the dictionary of an electrician. In it, the term stands for the movement of electrons through a conductor or ions through an electrolyte.
Depending on the movement of electrons or ions inside the conductor, the following are distinguished 
types of currents:
- constant;
- variable;
- periodic or pulsating.
Basic measurement quantities
Electric current strength - the main indicator used by electricians in their work. The strength of the action of the electric current depends on the magnitude of the charge that flows through the electrical circuit for a set period of time. The more electrons flowed from one beginning of the source to the end, the greater the charge transferred by electrons will be.
Current strength - a quantity that is measured by the ratio of the electric charge flowing through the cross-section of particles in a conductor to the time of its passage. The charge is measured in coulombs, time in seconds, and one unit of the strength of the flow of electricity is determined by the ratio of charge to time (coulomb to a second) or in amperes. The determination of the electric current (its strength) occurs by sequentially connecting two terminals in the electrical circuit.
When an electric current works, the movement of charged particles is carried out with the help of an electric field and depends on the strength of the movement of electrons. The value on which the work of the electric current depends is called voltage and is determined by the ratio of the work of the current in a particular part of the circuit and the charge passing through the same part. The unit of volt is measured with a voltmeter when the two terminals of the instrument are connected in parallel to the circuit.
The value of electrical resistance is directly dependent on the type of conductor used, its length and cross-section. It is measured in ohms.
Power is determined by the ratio of the work of the movement of currents to the time when this work took place. They measure the power in watts.
Such a physical quantity as capacity is determined by the ratio of the charge of one conductor to the potential difference between the same conductor and the neighboring one. The lower the voltage when the conductors receive an electric charge, the greater their capacity. It is measured in farads.
The magnitude of the work of electricity at a certain interval of the chain is found using the product of the current strength, voltage and the time interval at which the work was carried out. The latter is measured in joules. Determination of the work of an electric current occurs with the help of a counter, which connects the readings of all quantities, namely voltage, force and time.
Electrical safety engineering
Knowledge of electrical safety rules will help prevent an emergency and protect human health and life. Since electricity tends to heat the conductor, there is always the possibility of a situation that is dangerous to health and life. To ensure safety at home must adhere to following simple but important rules:
- Mains insulation must always be in good condition to avoid overloads or the possibility of short circuits.
- Moisture should not get on electrical appliances, wires, shields, etc. Also, a humid environment provokes the appearance of short circuits.
- Be sure to do grounding for all electrical devices.
- Overloading the wiring must be avoided as there is a risk of ignition of the wiring.
Safety precautions when working with electricity involves the use of rubberized gloves, mittens, rugs, discharge devices, grounding devices for working areas, automatic switches or fuses with thermal and current protection.
Experienced electricians, when there is a possibility of electric shock, work with one hand, and the other is in your pocket. This interrupts the hand-to-hand circuit in the event of unintentional contact with a shield or other grounded equipment. When igniting equipment connected to the network, extinguish the fire exclusively with powder or carbon dioxide extinguishers.
Application of electric current
Electric current has many properties that allow it to be used in almost all spheres of human activity. Ways to use electric current:
-
carrier of dissimilar signals in household appliances (landline telephone, television remote control, door lock button), as well as in special communications and radio; - energy carrier in engines, generators, accumulators;
- supplier of heat energy in heating devices, furnaces, electric welding;
- light energy source in signaling and lighting devices;
- obtaining materials by electrolysis;
- creating sounds and music with power tools;
- electrodiagnostics in medicine, treatment with electrical stimulation.
Electricity is the most environmentally friendly form of energy today. In the conditions of the modern economy, the development of the electric power industry is of planetary importance. In the future, if there is a shortage of raw materials, electricity will take a leading position as an inexhaustible source of energy.
