Do you know everything about basic electricity? If your answer is no. So you are in the right place, in this article we are going to talk about everything you need to know so as not to be embarrassed, such as basic electricity calculations, which is an electrical current, voltage, power, resistance and electrical magnitude.
What is electricity?
Electricity is the study of several phenomena related to the presence and movement of electrons. In Physics, it is the area that studies the phenomena caused by the presence and movement of electric charges such as electrostatics, electrokinetics, electromagnetism and electrodynamics.
What are the electrical quantities?
Electric current, electric voltage, resistance and electric power are examples of electrical quantities, and the quantity is basically everything that can be measured or qualified, and they can be vector or scalar.
Main electrical quantities:
The electric current is characterized by the ordered flow of electrons, where its unit of measurement is given in ampere (A). The electric current can be continuous or alternating, that is, it may or may not vary its value and direction as a function of time.
The electric voltage that is also known as the potential difference (DDP) is the force needed to move electrons, thus creating an electric current. The unit of measurement used for electrical voltage is the volt (V). Just like the electric current, the electrical voltage can also be continuous and alternating, so that continuous electrical voltage does not change in polarity over time, whereas alternating voltage changes in its polarity as a function of time, according to its frequency, which is also an important electrical quantity.
The electrical resistance basically hinders the passage of the electrical current, because the electrical resistance generates an obstacle, which makes the electrical current have difficulty in traveling through a certain conductor when it is subjected to a certain electrical voltage. The unit of measurement used for resistance is the ohm (Ω).
Electrical power is the electrical work performed by electrical current over a period of time. Electrical power is responsible for converting electrical energy into another type of energy. As, for example, in the shower, convert electrical energy into thermal energy, and the greater the electrical power of the shower, the hotter the water will be, and the lower the power of the shower, the colder the water, if we consider the same flow of water for both cases. The unit of measurement used for power is the watt (w). In addition, we can mention that there are three types of electrical power, which is reactive, active and apparent power.
What is the electrical circuit?
The electrical circuit is a closed path where the beginning and end are at the same point. A basic electrical circuit consists of a source, load and electrical conductor. The source can be a cell, battery, plug or another source, where there is a difference in electrical potential. The load that will consume the electrical energy of the circuit, for example, lamp, computer, television, etc. The electrical conductor (wire and electrical cables) is responsible for conducting the electrical current from the source to the load of the circuit that consumes it.
When there is more than one load we can have different types of an electrical circuit. For example, series circuit, parallel circuit and mixed circuit.
The series circuit indicates a sequence in the connection, for example, in the connection of three lamps in series. Following the path taken by the electric conductor, we see that the circuit is closed starting and ending at the same point, so that the electric current travels only a single path so that the electric current travels only a single path
In the parallel circuit, the electric current divides when it arrives at the node (splice or derivation), so the current will have two or more paths to follow, always having greater electrical current through the path of least resistance. Check the image below for the connection of three lamps in parallel.
The mixed circuit is the junction of the circuit in series with parallel as, for example, in the connection of three lamps in a mixed circuit illustrated in the image below, the conductor passes through the first lamp and then makes a derivation in the conductor, being divided for the other lamps .
Resistor association is made in a circuit that has more than one resistor, and there are three types of resistor associations, in series, parallel and mixed. The association in series of resistors and basically indicates a sequence in the connection of the resistors, where the electric current that passes through the resistors is the same. To calculate the equivalent resistance of a resistor association in series, add the resistances of each resistor.
In the association of resistors in parallel, the resistors are connected at two points in common, thus receiving the same electrical voltage. To calculate the equivalent resistance of the parallel association of resistors, the resistances must be multiplied over the sum of the resistors. In circuits with resistors of the same resistance, the resistance of a resistor can be divided by the number of resistors in the circuits, all resistors must have the same resistance to apply this formula.
In the mixed association it is the set of serial and parallel associations. To calculate the equivalent resistance in the mixed association, you must apply the series and parallel association formula.
The Ohm’s Law are fundamental laws for electricity. It was discovered by Georg Simon ohm, so it received the name of ohm laws. There are two ohm laws, the first consists of the quantities voltage, current and resistance. In the first ohm law, Georg connected a source of electrical voltage to a load, and observed the presence of electrical current in that circuit, then Georg changed the electrical voltage and noticed a different electrical current. In this way, for each applied voltage a different current was registered and whenever Georg gave the voltage to the electric current he always found the same number. This number was called electrical resistance, so he got the electrical formulas.
In the second ohm law, it talks about resistance and resistivity and came to complement the first ohm law. Resistance is an obstacle that makes it difficult for electrons to pass through the conductor. This resistance can be altered by some factors, for example, the conductor’s material, or its length and gauge.
Resistivity is a property of the material itself that the conductor is made of, some materials will have the ability to conduct electricity and the other will be difficult, this will be expressed as a quantity which is the class of resistivity, a way of giving unity to that resistivity, the length and conductor gauge can also interfere with this resistivity. And these factors resulted in a mathematical formula.
In this video from the World of Electrical you can see in much more detail how to apply ohm’s law and how it was formed!
Electricity is very wide, but we show you the basics you need to know about the subject, such as the definition of electricity, electrical quantities, electrical circuit, resistor association and ohm law. This article is one of many that we talked about electrical in the World of Electrical, feel free to know our other articles and stay on top of the subject.