The foundations of electricity

The foundations of electricity
(A) classification of materials as electrical conductivity
Materials are classified into three types according to the conductivity as follows:
 
1 - conductive materials - and are substances that allow the passage of electric current through such as copper; aluminum; and other metal conductive of electricity; and materials ranging in conductivity as the resistivity of each material.

2 - insulating materials: These are materials that do not allow the passage of electric current through; and because of the internal structure and the strong interdependence between the atoms; such as wood; rubber; porcelain; and other insulating materials.

3 - semiconductor materials: the materials located between the material conductive and insulating materials in terms of the delivery of electricity; other words Articles semiconducting be a buffer at a temperature of absolute zero and under the influence of temperature begins conductivity increase as a result of the disintegration of the strong link between the atoms by heat; and of semiconductor materials germanium; silicon.
(B) the concept of current and voltage and electrical resistance:
(1) Power Supply:
If you connect a copper wire with a source of electric power such as the battery; leads to the movement of electrons inside the wire; and from that deduce a definition of electrical current.Power Supply: is the amount of cargo passing through a conductor under the influence of an external force resulting from a battery electrical source;The direction of movement opposite to the direction of the electrons (the direction of current from positive to negative).



The following equation method of calculating the value of electric current:
V = k ÷ nWhere: T: current (mA)
           
As: electric charge (coulomb)
           
N: time (seconds)
Example: Calculate the amount of electricity if it is known that the amount of electric charge passing in the connector within 4 seconds equal to 8 Colom.
Solution: -
       
Data: find the required current and known value of the shipment and the shipment time, where (k) equal to 8 Colom; and the amount of time (n) 4 seconds
Apply to the power law v = k v ÷ n = 8 ÷ 4 T = 2 mA

Types of electricity:1 - DC power: who is the current value and its direction remains constant over time; and sources of gray DC accumulator (battery) used in cars.
 
2 - alternating current (AC) is the current value of the change and direction change with time; and the AC current generated from the power plant that provides electricity for residences.
 
Forms of waves of the alternating current (AC):
AC square wave form of AC wave form of the age saw the AC sine wave form
(2) voltage (voltage difference):
  
Requires entry into an electric current to the existence of the power of affecting the electrons; and can be an influential force is the potential difference or electromotive force or voltage, all labels may be similar in meaning.It can be defined: as a force that forces the electrons (charges) to move in a particular direction through a conductor; cause any flow of current supply.
 
Known and potential difference: Balchgl effort to move electric charge from a point less effort to the highest point effort.And can be achieved according to the following equation:
C = u ÷ kWhere: A: The difference voltage (volts) u: work done (Paljol)
          
As: the amount of electric charge (Balcolom)

Article and electricity

Article and electricity
Divided material for the passage of electric current in which to:
1 - conductive material: -A material that allows for the passage of electrical current which is also where the material that contains free electrons, This article may differ with each degree of the quality of delivery of electricity, where we find that silver is the finest example of the electric conductive material and then the rest of the material according to the quality of the connection.
2 - insulating material: -A material that resists the passage of electric current, namely, also differ in degree of isolationWhere we find that the solid mica, wood, glass and plastic insulation from the finest materials and then comes the rest of the material according to the quality of insulation.
3 - semiconductor material: (semi-conductor) (Semi - conductor): -A material that allows the passage of electrical current which in one direction only, such as Uniting (rectifiers)

Resistance and power
Can say that the resistance is a feature article of resistance to the passage of electric current, and the unity of this resistance is the Ohm! Resistance (m) and one ohm made by the Chamber that on both sides by voltage (c) one volt so that the current (c) passing in this article amount and one amp {.

 
Resistivity: -Can say that the resistivity of the material is}: resistance conductor length and one centimeter in cross-section area of ​​one square centimeter in the direction of flow of current; and its symbol (p) is directly proportional to the length (l)And inversely with the sectional area of ​​Mosul (o) {.If (m) a symbol of resistance, (l) the code length of Mosul; (o) cross-section area code
 
The law of the resistance as follows: -


M = p × s / o Om

The concept of current and voltage and electrical resistance of electric current

- The concept of current and voltage and electrical resistance of electric current:
 - If you connect a copper wire with a source of electric power such as battery, thus leading to the movement of electrons inside the wire, and from that deduce a definition of electrical current. Power Supply: - is the amount of charge passing through a conductor under the influence of an external force resulting from a battery electrical source. The direction of movement opposite to the direction of the electrons (the direction of current from positive to negative) and represent the following equation method of calculating the value of the voltage v = k ÷ n, where: - T: - current (amp) as: - electric charge (coulomb) N: - Time (seconds) Example: - Calculate the amount of electricity if it is known that the amount of electric charge passing in the old connector 4 seconds equal to 8 Colom. Solution: - data - to be a current and known value of the shipment and the shipment time, where (k) equal to 8 Colom, and the amount of time (n) 4 seconds to apply the current law v = k ÷ n T = 8 4 ÷ T = 2 mA types of power supply 1 - DC: - is the trend that the remaining value and direction consistent with the passage of time, and from sources of direct current accumulator gray (battery) used in the automotive voltage (voltage supply) needs into force of the electric current to the presence of force affect the electrons, and these can be an influential force is the potential difference or electromotive force or voltage, and all the labels have similar meaning. It can be defined - as a force that forces the electrons (charges) to move in a particular direction through a conductor, which caused the entry into force of electricity. Known and potential difference: - Balchgl effort to move electric charge from a point less effort to the highest point effort. And can be achieved according to the following formula: - P = u ÷ k where: - P: - Voltage Supply (Balfolt) u: - work done (Paljol) as: - The amount of electric charge (Balcolom) Example: - Calculate the potential difference between two points in the electrical system if the work done Jolla 60 to move the electric charge of 20 Coulomb. Data: - u = 60 Gul k = 20 the Coulomb solution: - P = u ÷ k P = 60 ÷ 20 q = 3 volt electrical resistance of known electrical resistance: - Objection article for the passage of electric current therein, and there are several factors depend on the resistance to any a connector. 1 - type of the material of which Mosul 2 - the length of Mosul, 3 - an area of ​​Mosul, section 4 - the temperature of Mosul, and these factors can be represented by the following equation and by which they can find if you know the value of the resistance data the equation m = (m n × s) ÷ Q where: - M: - Resistance to Mosul - in ohms () for: - the length of Mosul - meter (m) Q: - sectional area of ​​Mosul (in meters square) (m 2) M N - resistivity of the conductor (. m) Example: - Calculate resistance of copper wire from a length of 300 meters and the area of ​​cross section 10 × 610 m 2, and it is known that the resistivity of copper, 1.78 × 810. M solution: - m = (m n × s) ÷ Q m = (1.78 × 810 × 300) ÷ 10 × 610 m 2 m = 0.534 ohm applications on Ohm's law the text of the Ohm's law (if passed an electric current in a conductor, the value of this current directly proportional to the voltage applied between the parties to this connector and inversely with the resistance). And is called Ohm's law relative to the world, George Ohm. Can be represented by Ohm's law the following equation E = P ÷ m, where T: - current in amperes P: - voltage Balfolt M: - Resistance in ohms example: - arrived resistance wire of iron $ 10 ohms with a source of electric Folatith 100 volts, what is the value of current flowing in the resistance. Solution: - according to Ohm's law, the E = P ÷ m T = 100 ÷ 10 c = 10 mA elements of the circuit (resistance, Mwasa, File) resistors: - the electrical resistance is the reluctance of material for the passage of electric current through it, and use the resistance as an electrical used in electrical circuits for various purposes. Types of resistors used in circuit resistance fixed: - is the resistance of a constant value does not change, and the value of the resistance written on the resistance the system colors, system numbers and types of resistors fixed resistors carbon resistors wired resistors layered metal resistance changing - is the resistance, which can change its value within a certain range of delivery methods resistors in the circuit 1 - connect the succession of 2 - connect the equivalent of 3 - connected to a compound containing such participation in brief: - The definition of resistance to electricity - a unit measure - the impact of Gul - the importance of electrical resistance - Types of materials in terms of resistance - resistance relationship Balmouselah - Types of resistance - how to determine the value of the resistance - Methods of delivery of the electrical resistance of resistors Electrical Resistance is a physical property means an interception (disability) for the passage of material through which electric charges. And resistance occurs when the electrons hit the mobile atoms in the material and release energy in the form of heat "effect Gul." Another definition of the resistance Electrical resistance = voltage / electric current R = V / I, a form of Ohm's law and a unit of measurement of resistance is measured electrical resistance in ohms and has the symbol Ω and reads Omega OMEGA definition Ohm Ohm is the resistance arising in the circuit occurs when voltage of $ Volta one measuring current of 1 volt and one amp 1 ampere. Was named Ohm to this unit in honor of the physicist, the German Georg Ohm Gourge ohm sporting image: Ohm = Volt / Ampere Ohm = Volt / Amp and can be obtained on the unity of the resistance by using a specific path of the current, which produces a resistance of ohms and one if Sri electric current through the column of mercury is equal to an intermediate section with an area of ​​1 mm 2 and a length of 1.063 meters mmmm2 Gul effect results from the passage of electric current in a metal carrier (or vector Omi) emission of heat, and the impact of this phenomenon is called Jules. In some cases, control the amount of this flow (heating), but in other cases dissipate this energy and produce undesirable effects. Given the energy produced by the impact Gul, the following equation: the importance of the electrical resistance Trjh importance of electrical resistance for the following reasons: 1. Protection, although they cause a waste of part of the energy they are necessary to protect some parts of the electrical circuits Some damage (melt) if passed by the stream is greater than a certain amount, such as those used in cars, which are called (FUSE), and some are cut off power automatically when you exceed the amount of specific, such as electricity meter used inside your home. 2. Control the intensity of current passing through it. 3. Control is also a difference in voltage between both ends. Types of materials in terms of resistance 1. Materials with very high resistance (insulation), such as glass, wood, plastic, air, 2. Materials with medium resistance (semiconductor) such as silicon and germanium 3. Materials with low resistance (connectors), such as copper, gold and silver 4. Materials with resistance to virtually non-existent: such as semiconductors, high-quality relationship is an inverse relationship Balmouselah resistance, good Valmousel be a small resistance and vice versa. Therefore, if you look at the electric wire that we use in our daily life you find a component of the metal part of the current and allows the operation of this part is covered with material such as plastics are high-resistance does not apply when the current from the outside

Important definitions, which is the gate of the electrical transformers in general

Important definitions, which is the gate of the electrical transformers in general ...

 
At first we have to more understanding well the following definitions:


Magnetic field:Is the region that develops around the moving electric charges affect any magnetic material or an electric charge moving within the region. 

Magnetic field lines:Imaginary lines indicates the direction at any point on the direction of the field.
 Magnetic flux:Is the total number of magnetic field lines that penetrate a specific area.
 Magnetic field strength:The number of field lines that cut unit area perpendicular to the direction at that point or is the force that affects the magnetic field on a positive electrical charge that moves the unity of speed at that point in the direction perpendicular to the direction of the field. 
Regular magnetic field:Is the area density Veidah amount equal and uniform direction at all points located in it. 
Tesla:Is the intensity of the magnetic field, which strongly affects the amount of one Newton on a positive charge and the amount of one coulomb moving at one meter per second in the direction of making a right angle with the direction of the field. 
Ampere's law:Total amounts of magnetic rotation on different parts of the closed path is directly proportional to the intensity of the power within that path.
 Electromagnetic induction:Is a phenomenon that generates a driving force and the sympathetic electrical current in a conductor cosplay influence the magnetic field. 
Faraday's law:Suit the driving force generated in the influential electrical connector directly proportional to the rate of change in the effective magnetic flux on the connector. 
Self-induction of the file:Is the ratio between the influential driving force generated in the file and the current rate of change in that file.
 Henry:Is to encourage self-change to a file if the current flowing at a rate of one ampere per second generated between the ends of a driving force sympathetic amount of one volt.
 Mutual induction between the two files:Is the incident magnetic influence between two adjacent or overlapping so that if you change the current in the one affected the other and resist the change in the first.
 Coefficient of mutual induction between the two files:Measured by the driving electric power generated in one of the two files when you change the intensity of the current in the other file at a rate of one ampere per second. 
The efficiency of the converter:Is the ratio between the electrical energy in the file to the secondary electric power in the primary or the file is the ratio between the ability of the secondary to the ability of primary education. 
Transport efficiency:Is the ratio between the electric power supplied to the places of consumption and the energy transmitted from the generating stations. 
Base Service Provider:The direction of the current generated in the file impressionist contrasts with the change in magnetic flux that causes it. 
AC:Which is the current magnitude and direction of change periodically with time.Inductive impedance of the file:Disability, or is the resistance encountered by the AC when it passed in a file because of self-induce.

Some questions and answers:
Why wrap a resistance wrapped double standard?To be the direction of current in a sub-file is reversed in the other branch Visawy spheres Amonatisaan Atdhadan and is equivalent to each other Vinadm self-induction in the file and the resistance becomes zero self-induction.
Why does not DC power adapter?Because the DC area generates a fixed intensity and direction in the sense that there is a change in magnetic flux which cuts the file is not generated by the secondary driving force electric sympathetic.
Why not pass current in the primary file for the adapter, although its connection to the AC cycle when the secondary file open?Generate a driving force because of adverse-effect self-induction in the primary file are almost equal and anti-momentum of the source file Vinadm the current in the primary does not occur in the consumption of energy.
Why current flows in the original file and the primary place for consumption of electric energy in the converter when the secondary department closed the file and the Department file closed primary?Because at the moment of the growth of the power the original file primary generated in the secondary stream cosplay Reverse This current generates a flood magnetically resists the growth of magnetic flux the original file primary weakening the driving force of reverse generated inductively self in the file primary Wimmer stream the original file, primary (urged mutual) occurs consumption of energy and notes here and there are two types of induction in the adapter first urged the self in the file shows the primary effect when the Department of Secondary and urged an open exchange between primary and secondary files when the file is the Department of Secondary and primary department closed the file.
Why become a circuit consisting of capacitor and AC power closed circuit?Since the capacitive impedance increase of less frequency and therefore allows the passage of heavy currents, high frequency circuit is considered closed.
Why become a circuit consisting of a source of AC power and urged the department open?Since the inductive impedance increases with frequency and thus be very large in the case of high frequency current does not pass and become an open circuit.
Why is the resistance of the ohmic value of one important change frequency while the source impedance inductive or capacitive have multiple values ​​when you change the frequency of the source?Because the ohmic resistance does not depend on the frequency of the source while the capacitive impedance is inversely proportional to frequency induction and resistance is directly proportional with him.
Why prefer to use the AC for DC?1 - because the AC can be raised or lowered by the driving power electrical transformers.2 - AC passes in the circle of the capacitor.3 - AC power can be converted to a continuous stream.
What are the factors that affect the self-induction?Increases the self-induction in the following circumstances:1 - increase the number of laps file 2 - increase the area of ​​section of the file and decrease its length.3 - If the file to the heart of magnetic material such as iron or iron powder or ferrite.And vice versa of course "in the previous three cases.
What types of files converted to the frequency?1 - low frequency files: the files that are used in circuits with low frequency. Circuits such as audio-frequency range where from 20 to 20 kHz files with a heart of iron.2 - average frequency files: the files that are used in medium frequency radios in the files with a heart of iron powder and some Ferret.3 - files HF: It is used in high frequency by more than 2 MHz. Smoothing circuits, such as files with a heart of an antenna.
What is the philosophy of electrical transformers work?When the flow of current in the first file (primary), it created a magnetic field variable to changing the current flowing in this file, and because of the second file (secondary (within the area of ​​the first file, the lines of flux (lines and imaginary indicates direction at any point on the direction of the field) and cut the second file Since the area resulting from the variable, the change in magnetic flux penetrating the files work on the movement of electrons to file the second and this movement is called thrust magnetic Magneto motive Force mmf) which cause the flow of current in the second file is called the current trend inferred inductively self between the file the first and the second file.As is clear to us that the heart of iron wrapped it close in the first two files by the AC and the second by the resistance of pregnancy and conductor in parallel with them Oossellscop body and the look of the form and watch the waves both in the device with the file of Mosul, Mosul, with primary and secondary fileNote generates a stream of almost similar to the current file in the primary and this is simply a work of philosophy and the theory of electrical converter.We also note that flood caused his vehicle AC voltage equal to a vehicle passing in the file and have the same value, but the difference between them?It is clear that the voltage wave and the wave flux is a clear difference is that the voltage before passing the file around the resulting flux angle (Fi) of 90 degrees, a quarter of a cycle.
The shape of the relationship of the sinusoidal current and voltage and magnetic flux together it is clear that the current and magnetic field are almost the same path, while progressing on both voltage-Fi angle = 90 degrees.

Transformers
Converters are used to raise or lower the voltage or current in electrical circuits. And adapters based on the so-called interactive feature induction (Mutual Inductance) in their work and therefore we will give an explanation of the cross before the urge to give details of the converter because it can not understand the work of the converter without the full absorption to induce cross-[Cross-induction (Mutual Inductance)
We explained previously in the Department of the basics that the file (inductor) is a tool that resist change in current, regardless of the direction of this trend. And we know the self-induction of the file that the ability to find the file on the effort to resist any change in the current force. It also runs when the AC (AC) in the file, it will produce a magnetic field on this file. If increased power increased distance of the magnetic field on the file and say if I said the distance around the current file.When we put another file in this magnetic field which increases and decreases, this magnetic field will generate a current in the second file, and this property is called the cross-induction (Mutual Inductance) Note that the AC, which is up to our homes with a frequency of 50 or 60 hertz. This means that when this current is going through in a file and it rises at least 50 or 60 times per second. Thus, the magnetic field in the file will increase and decrease of 50 or 60 times per second, it is when a magnetic field variable; if we passed a current constant (DC) in the file Primary will produce a magnetic field in the file, the secondary, but this area magnetic field constant is a variable to be the result of a steady stream. And therefore will not result in any effort in the file right.Now if we opened the key to power off the magnetic field will change in the secondary and the file will result in an effort called the induced voltage (induced voltage), causing the flow of current in the secondary file. As mentioned previously, the file is resisting any change, therefore, the direction of the trend will be in such a way is trying to keep the magnetic field as it is without change.Now what would happen if we closed the key again to stop the trend? Will increase the current in the left file of course, the file will try to keep the secondary magnetic field as it is, therefore, will be generated by the counter-current produces a magnetic field and opposite to the increase in the resistance of the magnetic field.The fact that any change in current in the Primary file affects the current and voltage in the secondary file is in fact the so-called cross-induction (Mutual Inductance)If you can know that cross-induction property that enables electric current in force in a wire or a file from a current in a wire or file another close to it; and this property is relied upon by the converter in his work.

Components of the adapter:

Converter consists of the following main parts:
Heart: It is a piece of iron
Master File: The entrance to the converter
Secondary File: The output converter
The Doctor and the main secondary wire is wrapped on the heart and Elamsan each other.
How does the adapter:
Adapter works only with alternating currents (AC) and not fixed currents (DC) When the AC power enters through the main file (primary) results in a magnetic field is concentrated in the heart. This goes a variable magnetic field coils and the secondary file is generated from that stream takes it.But how to define the voltage and current issued from the switch?
Efforts and movements in and out of the converter depends on the number of rolls of the two main and secondary education. If the number of laps file secondary is greater than the number of rolls of the master file, the effort out of the converter will be much greater than the inside, while the output current is smaller than the current home. In this case, the adapter uses to enlarge the effort; If the number of turns the secondary file is less than the number of laps the main file outside the voltage of the transformer will be less than the voltage inside, while the output current is greater than the current home. In this case the converter is used to reduce the effort 0
Converter and electronic circuits:
We mentioned earlier that the adapter works only with the efforts and reluctant currents (AC), while most of the electronic circuits operate with the efforts of the fixed (DC). If the adapter is not fit for direct use to feed the electronic circuits where you must convert the voltage from the secondary of the converter to a constant voltage (DC).
Types of transformers:
Adapters are available in different shapes and sizes, according to several very large mismatch of Use, including the very young and the most important types of power transformers, adapters and sound.

The story of the invention of electricity


The story of the invention of electricity

He was a genius of electricity is the British chemist Sir Michael Faraday, born in London in 1791, where otherwise there was no talk of the use of electricity.

The encounter that made ​​the first electric motor before the possibility to discover how the invention of electricity, and therefore he could not when his invention but to use a battery to run it.

In 1821 the noted Danish professor Hans Christian Ørsted, that when the magnetic needle near the drooping of carrying electric current epidemic, the needle is moving away from or approaching it.

Thus, the Faraday had decided that there must be a relationship between electricity and magnetism, and after numerous experiments in 1821 attached a piece of copper wire from a hook so that the lower end of affecting the mercury placed in the dish, and when he passed a current from a battery through the lift took place end of the wire remained going to charge the battery runs out.

It was not the first drive of the value of this process because it can not move anything, but he has proven the interdependence of electricity and magnetism are closely interrelated.