Electrical circuit Electrical doses are produced by connecting several bipolar devices together to form a closed network in order for them to -work. It is a closed path through which current can pass, made up of four small electrical components: the source, the lamp or any other load, connecting wires, and a switch. When the lamp is closed, there is a decrease in the lighting of the lamp due to the passage of electrical current. Peace plants are used in the electrical circuit.*The electrical circuit is called a circuit because an electric current does not flow in the circuit unless the circuit is closed like a circuit. It is called electric because its work depends on electricity. The electric current that flows in conductors and electrolyte solutions arises as a result of the movement of ions - which are molecules that carry a negative or positive electrical charge. Electrons are the moving charges in conductive materials, and ions, both negative and positive, are the moving charges in electrolyte solutions, just as a battery works. The power switch controls turning the lamp on or off. It works to close the electrical circuit so that the current can pass (as the electrical circuit is complete) and the lamp lights up. We say that the circuit is clased. Or it warks to agen ar break the circuit, so the electrical current does not pass through the broken circuit, and the lamp does not light, and we say that the .circuit is open Note: The column Is called an electrical source and the lamp is called a receiver. The battery post, lamp, and circuit breaker (switch) are electrical components, each with two leads called dipoles. One pole from which current enters and the other pote -from which current exits A simple electrical circult consists of two dipoles connected together by wires (conductors), and contains a current source, a switch, and a receiver (lamp, radio, refrigerator, etc)Components of an electrical circuit We use symbols for its various components \ - Electrical source (battery ) The first component in an electrical circuit is the source of electrical energy that allows electrons to move. This source can be a battery or an AC source, the source has a positive terminal and a negative terminal from where charge can flow from one to the other. This push of the electric charge is called the potential, the potential of which is measured in volts. 5 si m 3 bs Y- Electrical load The load is any electrical device or equipment that consumes electrical energy and converts it into light energy, as in light bulbs. Or to kinetic energy, as in electric motors, or to thermal energy, as in electric heaters.—6— _/ - — ~N Y - connected wires These wires are used to connect various parts of circuits and electronic components of electrical devices. The connection wires in the electrical circuit are essential, as without them, the electric current cannot pass nor energy can be transferred from the source to the load. Therefore, the wires are a major part of the circuit and are what ensure the circuit's path is closed and continued. Cable Jacket ‘Wire Insulation Stripped WireThe basic material for these wires is copper or aluminum, and they are insulated with plastic made of polyvinyl chloride (PVC). The insulators of the internal connection wires are in various colors to make it easier to distinguish between them. Multifilament wires are characterized by the greatest flexibility and facilitate the process of soldering wires with various .components of electrical appliances. £- Electrical switches A switch is an electrical component whose function is to allow or stop the flow of electric current in an electrical circuit. This switch works either by making the electrical circuit closed to start the flow of electrical current, or it acts as a breaker in the electrical circuit to stop the flow of electrical current. SO Additional components in the electrical circuit. The main components of any electrical circuit are the source, wires, load and switch, and some electrical circuits can contain additional electrical elements.©. The electric lamp A lamp is a device that converts electricity into light by passing current through a thin wire called a filament. The filament Is usually made of tungsten, a material that generates light when .electricity passes through it \- Resistance Resistor can be used to control the amount of electric current in an electrical circuit. Resistance has two ends, so current can flow through one end and exit through the other. Resistors may be made of metal wire (usually an alloy of two or more metals (which have high resistance)) or carbon. Carbon conducts electricity but does not conduct electricity like most metals, so high-resistance resistors are made of graphite because its melting point is very high, Y - Condenser A capacitor is an electrical device that Is used to store electrical energy and consists of two conductive plates with an insulating material between them. A capacitor [s one of the most common components in electrical circuits. Capacitors are widely used in electrical and electronic circuits. For example, capacitors are used to smooth alternating current. In telecammunications equipment — such as radio receivers — to set the desired frequency, in time delay circuits, and electrical filtering circuits. A- File An electric coil is a wire wound in a spiral with a large number of turns. It is wrapped around an iron cylinder. It generates a magnetic field when an electric current passes through it. The coil is used in oscillation generating circuits, filtering circuits,— and in the manufacture of electrical machines such as transformers, generators, and electric motors, 4 - Protection devices To ensure that the electrical circuit continues to operate safely, protection is one of the important components. This protection may be in the form of fuses, which are the cheapest and are usually available in various shapes, capacities, and characteristics, or in the form of circuit breakers, which are more complex and more expensive. Protection works by cutting off the electrical circuit when a current higher than what is permissible passes through it. This is called overload protection. The circuit can also be cut off when the source voltage drops below what is permissible, or when the load temperature increases above what is permissible. Electrical circuit elernents, symbols and functions Voltmeter It is a measuring tool used to measure the voltage or the difference in electrical potential between two points in an electrical circuit, without causing any change in the voltage in that circuit. The voltmeter in an electrical circuit is symbolized -by a circle with the letter V inside it Ammeter It is a measuring instrument used to measure electrical current, whether direct current or alternating current. The current is Measured through a group of !ow-resistance colts and inductive reactors. The ammeter is symbolized in an electrical circuit bya circle with the letter A inside it.Inductors Inductors are known as metal coils used in electrical circuits, which have the ability to generate magnetic fields when an electric current passes, in addition to being able to create magnetic fields in the wires near them. Inductors store energy in the form of an electromagnetic field, and in the electrical circuit itis symbolized by: Spiral wire shape Dilatants Capacitors are one of the elements of the electrical circuit that store charge. They consist of two close, often parallel plates. It is worth noting that it is possible to charge a capacitor by connecting it to a battery, and it can also be discharged by removing the battery and connecting it to one of the elements of the electrical circuit. Other, capacitors can release the charge faster than batteries and do so periodically; It can be charged, then released, then charged more than once, which is exploited in some circuits, such as the flash in a camera, and capacitors in an electrical __| |___ circuit are symbolized by the symbol The relay It is one of the elements of the electrical circuit that is used for protection. It is an electromagnetic switch that operates using a fairly small electrical current, but it can turn on or stop a much larger electrical current. It is worth noting that relays can work either as switches, that is, turning on or off, or as amplifiers, that is, switching currents. Small to larger streams.Classification of electrical circuit components The elements or components of an electrical circuit are classified into two parts: active elements and inactive elements, depending on their ability or inability to generate selectrical energy. Below Is a simple explanation of that Active Circuit Elements: These are the elements capable of generating electrical energy, such as batteries, generators, operational amplifiers, and diodes. The power source elements .are the most important active elements Passive circuit elements: These are the elements that consume electrical energy, as they are unable to generate it. The flow of electrons through the circuit can be controlled through them. Examples include: electrical resistance, inductor or coil, electrical capacitor, electric lamp, and all electrical load devices. Types of electrical circuit It is necessary to know the dimensions of the electrical circuit elements and their modern types. Because many of the compounds used in their classification, a circuit can first be classified either into electrical preference circuits on the toilet or electrical circuits in parallel, as it is called the circuit whose components are connected in one continuous loop as the electrical circuit that is not available in series, and the electrical circuit is preferred The network is in balance, it is the circuit in which its components are connected in representational parties, and from everything and not limited to the circuit Electric is actually a combination of both; This is because each type has different characteristics; When any element in the | electrical circuit connected in series fails, the entire circuitstops working, which does not happen in a parallel circuit. This is why the series circuit may be useful for safety features such as fuses, but it is not very suitable for Christmas lights. In addition to that, the production of... Parallel circuits are more expensive to produce than series circuits. The second method of classifying circuits is the method based on the type of energy. Thus, they are either direct current circuits (DC) or alternating current (AC) circuits, as direct current is the flow of electrical current in one direction only, while alternating current is the flow of electrical current back and forth in both directions. It is worth noting that the type of current that is obtained from the plug In homes or establishments it is AC current; This is due to the ease of generating alternating current electricity and transmitting it over long distances without losing much energy during. However, many devices, especially small devices, still use direct .current. Types of circuit depending on the nature of the electric current The electrical circuit is accordingly divided into two types, the circuit with a current source The circuit has an alternating current source. DC circuit In direct current, the current generated from the source (battery) is always constant and is related to the characteristics of the source itself (battery), and the circuit can be divided according to the distribution of the active and passive elements in it into a circuit connected in series and a circult connected in branches, and'they differ from each other in that in series the current Constant in the various parts and elements of the circuit, while the voltage is variable. In contrast, in the case of acircuit connected in a branch, the voltage is constant and the current is varlable. Series ~ parallel Julaill ple Vyogall Sylall — gill ule Wysogall SyLul Alternating current circuit In alternating circuits, the source generates an alternating current (such as an electric generator). The difference from the direct current lies in that the characteristics of the alternating current, such as the intensity and the potential difference (voltage), are variable and take variable values, but they are constant in changing with time. In general, most electrical appliances and appliances Which requires high current intensity and operates with alternating current. Types of circuits according to their elements. The electrical circuit is divided into two types accarding to its components; Non-linear linear circuitA linear circuit is a circuit in which all the characteristics of the circuit (such as the amount of resistance, capacitance, } capacitance, frequency, wavelength, etc,) are constant. In other words, we call the circuit In which the characteristics of its elements do not change with changes In intensity and voltage, a linear circuit. In contrast, in a non-linear circuit, the characteristics of its elements change constantly with changes in the magnitude of the intensity of the current and the difference in potential of the source. The circuit is unidirectional and bidirectional Ina single circuit, the characteristics change with the change in thé direction of the current or voltage of the source. In other words, the single circuit allows the current to pass in one direction and prevents it in the other, which leads to a change in its characteristics when the directions or poles of the source are reversed. A diode rectifier is an example of a one-way .circuit element In a two-way circuit, the characteristics of the circuit remain constant even if the direction of the source poles is changed or reversed. That is, the double circuit allows the current to pass in both directions without obstructing one direction and allowing the other. An example of this is conductors, such as conductive copper wires, which allow the electrical current to ‘be transmitted in more than one direction. Types of electrical connections In the electrical circuit, depending on the type of current that flows in the circuit, whether it is alternating current or direct. current, or depending on the components of the circuit when there are two or more electrical devices present in a circuit thathas a power source, there are two basic methods through which the two devices can be connected, and they are as follows: Straight delivery This type of connection is usually linked to a laboratory experiment to make it easier to understand. This is done by creating a series electrical circuit by connecting a group of light bulbs so that there is one path for the charges to flow. Then the bulbs are added to the same line without a branch point. As the number of bulbs increases, the brightness will decrease. Each lamp gradually, which means that the total current inside the serial circuits decreases with the increase in the value of the total resistors connected to them. It is worth noting that when one of the lamps connected in series in the circuit fails; All other lights will go out immediately, so the operation of every device connected in series in the circuit is a condition for the continuity of power for all devices connected to it. sll H+Calculate equivalent resistance Resistors are connected in series by connecting the first end of the first resistance to the voltage source, then connecting the second end of it to the second resistance, connecting the second end of the second resistance to the third resistance, .and so on. When resistors are connected in series, the same value of electric current flows with each resistance. The current passes through the first resistance, then the second, then the third until it reaches the last connected resistance. However, in such circuits, the potential difference across each resistance is different from the other, and the connected circuit is considered The series is one of the simplest electrical circuits, because if a failure occurs in one of the resistors, the electrical current stops flowing and thus the entire circuit is shut down. The total value of the sum of the resistors connected in series is calculated by their algebraic sum. If we have a circuit in which the second end of the first resistance (R1) is connected to the first end of resistance R2, and the second end of R2 is also connected to the first.end of R3, then the value of the total tresistance is (Rtotal) Equal Total resistance of the system = first resistance + second resistance + third resistance +..... + last resistance. ‘And with symbols Rtotal = R1+R2+R3+.... +RExamples of calculating resistors in series ‘Here are several examples of connecting resistors in series Example 1 Two electrical resistances, one with a value of 100 ohms and another with a value of 200 ohms, are connected in series. What Is the total resistance in the circuit? tthe solution “We have two resistances R1= 100 and R2 = 200 To calculate the equivalent resistance, we add the two tresistances according to the following law Rtotal = R1+R2+R3+.... +Rn Equivalent resistance (Rtotal) = 100 + 200 Rtotal = 300 ohms Example 2 An electrical circuit contains 3 resistors connected in series. A current equal to 20 amperes flows through the second resistance. What is the value of the current that flows through the first resistance, if the values of the three resistors are 2 ohms, 3 ohms, and 6 ohms in series?the solution: Referring to the rule that says that the value of the current that flows through resistors connected in series is equal, this means that the current that flows through the second resistor is equal to the current that flows through the first and third resistors, which is equal to 20 amperes. Example 3 An electrical circuit containing 5 resistors connected in series, through which a current equals 30 amps flows. The values of the five resistors are 2 ohms, 3 ohms, 6 ohms, 3 ohms, and 9 ohms, respectively. If the second resistor fails, what is the value of the current that flows through the resistance First. the solution: Resistors are connected in series by connecting the second end of the first resistance to the first end of the second resistance, and the second end of the second resistance to the first end of the third resistance, and so on. Therefore, when the second resistance fails, the entire circuit will fail and no current will flow through it. Connecting in paralle! The basic idea in parallel circuits Is that all components are connected to each other, and there are no more than two sets of points electrically in common, regardless of the number of electrical components connected and the presence of many paths for the flow of electrons, but the voltage remains constant on all paths, and when connected The method ofconnection is a laboratory experiment, as is the case with series connection, using the same lamps and wires, but by connecting each lamp to a different flow path of electrons, and by connecting an indicator lamp outside the branches to study the total current. It will be observed that the brightness of the indicator lamp increases with the increase of the total resistance connected to the circuit, and when one of them breaks down lamps located in one of the branches, the flow will be interrupted Only the branch in which the faulty lamp is located, and the circuit will complete its function by feeding the .test of the branches The equation for calculating the equivalent resistance of a group of “n” resistors connected in parallel:CORI See re parallel naib: tapet tier MOO Reet VOG2 ‘ \ 1 Wyo 1000) (Og, 200) Re = 4004) L, Rr = BQ ADK, TOR) WV = 40002 + 1002 + 802+ 1002 What is the difference between parallel and sertes cliculty# The main difference between parallel ani series elreults Hes in the amount of clectrleal current paxalng through each component of the elrcult. In a series clreult (connected to series), the same amount of current Haws througt all the components placed (1 It, while fi a parallel clreult (connected tn parallel) the flowing current Is divided Frou the source to a group of currents flowing through the components that make up the circuit. As for the electrical voltage, Ina serlon Clrcult itis divided among the components of the clreult, while Ina parallel circuit, the voltage Is constant actows all ity components,ls power equal in parallel and series circuits? The power consumed in resistors connected in parallel is more than the power consumed in resistors connected in series at the same value of the applied voltage. Thank you