For many applications,we required d.c. supply.Due to an economical proposition,the Electric Power is almost exclusively generated,transmitted and distributed in the form of Alternating Current.
For the successful operation of all Electron Tubes and Semiconductor Devices d.c. supply is required.Batteries can not be used for the purpose as they are costly and required frequently replacements.
Considering all these problems,it is necessary and also economical to convert available a.c. power supply into d.c. power supply.
Conversion of a.c. into d.c. can be achieved by Mechanical Devices also,yet Rectifiers are mostly used for the conversion purpose due to its simplicity,cheapness,efficiency,longer life and noiseless operation.
From above description we can define a Rectifier as "An Electronic Device that converts Alternating Current into Direct Current."
A Rectifier,changes a.c. supply into d.c. supply by eliminating the negative half-cycle of the Alternating Voltage.It may be thought of as a Switch that closes a load Circuit during the positive half-cycle of a.c. supply and opens the Circuit during the negative half-cycle.
Therefore,A Rectifier provides one-way path for Electric Current,means conduction takes place in one direction only.It is in this way that a Rectifier converts an Alternating Current into Undirectional Current.
Rectification Efficiency:-
The ratio of d.c. Power Output to the a.c. Power Input in a Rectifier is known as Rectification Efficiency.
Single Phase Vacuum Tube Rectifiers may be classified in two categories,that are as below.
01)Half-Wave Rectifier:-
It conducts only on the positive half-cycle of input a.c. voltage.
02)Full-Wave Rectifier:-
It conducts on both half-cycles (means positive and negative) of a.c. input voltage.A Full-Wave Rectifier Circuit can supply more d.c. output power than the equivalent Half-Wave Rectifier.
In this post I will cover this much information only,for the detail study,you can wait for another posts or find it out from searching elsewhere.
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What Are The Limitations In Operating Conditions Of Vacuum Tubes?
Different types of Vacuum Tubes and its uses.
What is the use of TRANSDUCER in Electronic circuits?
Wednesday, July 30, 2008
Tuesday, July 29, 2008
What Are The Limitations In Operating Conditions Of Vacuum Tubes?
The Vacuum Tubes will always give satisfactory performance in a Circuit if they are operated under proper condition.Actually this is the basic requirement of any Electronics Devices or Circuit.We have to take due care about the requirement of such Devices.Any deviation may result in the damage of the Vacuum Tube.The Vacuum Tube Manufacturers publish manuals indicating the limitations in the Operating Conditions.
There are many Limitations in Operating Conditions of Vacuum Tube,but following three are important from subject point of view.
01)Peak Inverse Voltage:-
The Maximum Reverse Voltage that can be applied across the Tube without Conduction in the reverse direction is known as Peak Inverse Voltage.
In the normal situation,the Plate of Tube is positive with respect to Cathode and Current flows from Cathode to Plate.However,if the Vacuum Tube is supplied with small reverse potential,normally no Current will flow.
If the reverse potential is increased,at one stage,the Electric Field becomes strong enough to tear Electrons out of the cold plate.As a result,Current starts flowing from Plate to Cathode (means in Reverse Direction).
This is undesirable and may damage the Vacuum Tube or other Electronic Circuit Elements.
02)Maximum Plate Current:-
It is the highest instantaneous Plate Current that a Tube can safely carry without damage to the Cathode and without undue Voltage drop in the Vacuum Tube.
03)Maximum Plate Dissipation:-
It is the maximum Power that a Vacuum Tube can handle without Overheating.During the Tube Operation,Electrons from Cathode bombard the Plate.
The Kinetic Energy of these Electrons is converted into Heat,due to which the Temperature of Plate Structure raises.If the Heat is produced faster than the Plate can dissipate it,the Temperature will rise to such a point as to either melt the Plate or cause Electron Emission from the Plate.
Therefore,Heat produced must be dissipated in order to keep the Plate Temperature within safe limit.
I have tried to give as much as knowledge,I have.You can search more details from other places.
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Different types of Vacuum Tubes and its uses.
There are many Limitations in Operating Conditions of Vacuum Tube,but following three are important from subject point of view.
01)Peak Inverse Voltage:-
The Maximum Reverse Voltage that can be applied across the Tube without Conduction in the reverse direction is known as Peak Inverse Voltage.
In the normal situation,the Plate of Tube is positive with respect to Cathode and Current flows from Cathode to Plate.However,if the Vacuum Tube is supplied with small reverse potential,normally no Current will flow.
If the reverse potential is increased,at one stage,the Electric Field becomes strong enough to tear Electrons out of the cold plate.As a result,Current starts flowing from Plate to Cathode (means in Reverse Direction).
This is undesirable and may damage the Vacuum Tube or other Electronic Circuit Elements.
02)Maximum Plate Current:-
It is the highest instantaneous Plate Current that a Tube can safely carry without damage to the Cathode and without undue Voltage drop in the Vacuum Tube.
03)Maximum Plate Dissipation:-
It is the maximum Power that a Vacuum Tube can handle without Overheating.During the Tube Operation,Electrons from Cathode bombard the Plate.
The Kinetic Energy of these Electrons is converted into Heat,due to which the Temperature of Plate Structure raises.If the Heat is produced faster than the Plate can dissipate it,the Temperature will rise to such a point as to either melt the Plate or cause Electron Emission from the Plate.
Therefore,Heat produced must be dissipated in order to keep the Plate Temperature within safe limit.
I have tried to give as much as knowledge,I have.You can search more details from other places.
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What is Thermistors means?
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Different types of Vacuum Tubes and its uses.
Saturday, July 19, 2008
Different types of Vacuum Tubes and its uses.
An Electronic Device,in which the flow of Electrons is through a Vacuum is known as Vacuum Tube.
A Vacuum Tube usually contains a Cathode which is called as Electron Emitter,an Anode which is called as plate (which is electron Collector) and one or more Electrodes called as Grids,for controlling the flow of Electrons between the Cathode and Anode.
These Electrodes are housed in highly evacuated glass envelope.The Anode is held at Positive Potential with respect to Cathode,so that Emitted Electrons are attracted to Anode to provide Current in Vacuum Tube.
The application of Vacuum Tubes are so varied that this has won a place in the Industrial and Commercial fields.These Tubes have been found wide applications in Radio,Long Distance Telephones,Sound Motion Pictures,Televisions,Radar and Industrial Automation.
Though Vacuum Tubes have been replaced by Semi-Conductor Devices these days,they are still used at many places in Electronic Circuits.
According to the number of Electrodes,Vacuum Tubes are classified as below.
01)Vacuum Diode:-
An English Physicist,Sir J.A.Fleming has first invented Vacuum Diode in 1904.This Diode is known as Fleming's Valve.This Valve was so insensitive that it found little immediate applications.Many improvements have been made later.
02)Vacuum Triode:-
An American Scientist Dr.Lee De Forest,has placed a Third Electrode in the form of Wire Mesh,between the Cathode and Anode of Vacuum Diode.The resulting Device was called Triode.It ushered in the Electronics Industry as we know it today.
03)Vacuum Tetrode:-
Although Triode can make Amplification,it presents the major limitations that Plate-to-Grid Capacitance causes feed back particularly at higher Frequencies.
The Plate-to-Grid Capacitance of a Triode can be reduced by inserting an additional Grid,called the Screen Grid,between the Control Grid and Plate.Such a Four Electrode Valve is known as Tetrode.
04)Vacuum Pentode:-
A Suppressor Grid,is inserted in between the Plate and Screen Grid of Tetrode to eliminate the undesirable effects of Secondary Emission.This gives Five-Electrode Valve and known as Pentode.
A Pentode,contains a Cathode,a Anode and Three Grids.The Grid closest to the Cathode is Control Grid,next is Screen Grid and the third is Suppressor Grid.
The Suppressor Grid is connected to the Cathode and serves to Suppress the effects of Secondary Emission.
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A Vacuum Tube usually contains a Cathode which is called as Electron Emitter,an Anode which is called as plate (which is electron Collector) and one or more Electrodes called as Grids,for controlling the flow of Electrons between the Cathode and Anode.
These Electrodes are housed in highly evacuated glass envelope.The Anode is held at Positive Potential with respect to Cathode,so that Emitted Electrons are attracted to Anode to provide Current in Vacuum Tube.
The application of Vacuum Tubes are so varied that this has won a place in the Industrial and Commercial fields.These Tubes have been found wide applications in Radio,Long Distance Telephones,Sound Motion Pictures,Televisions,Radar and Industrial Automation.
Though Vacuum Tubes have been replaced by Semi-Conductor Devices these days,they are still used at many places in Electronic Circuits.
According to the number of Electrodes,Vacuum Tubes are classified as below.
01)Vacuum Diode:-
An English Physicist,Sir J.A.Fleming has first invented Vacuum Diode in 1904.This Diode is known as Fleming's Valve.This Valve was so insensitive that it found little immediate applications.Many improvements have been made later.
02)Vacuum Triode:-
An American Scientist Dr.Lee De Forest,has placed a Third Electrode in the form of Wire Mesh,between the Cathode and Anode of Vacuum Diode.The resulting Device was called Triode.It ushered in the Electronics Industry as we know it today.
03)Vacuum Tetrode:-
Although Triode can make Amplification,it presents the major limitations that Plate-to-Grid Capacitance causes feed back particularly at higher Frequencies.
The Plate-to-Grid Capacitance of a Triode can be reduced by inserting an additional Grid,called the Screen Grid,between the Control Grid and Plate.Such a Four Electrode Valve is known as Tetrode.
04)Vacuum Pentode:-
A Suppressor Grid,is inserted in between the Plate and Screen Grid of Tetrode to eliminate the undesirable effects of Secondary Emission.This gives Five-Electrode Valve and known as Pentode.
A Pentode,contains a Cathode,a Anode and Three Grids.The Grid closest to the Cathode is Control Grid,next is Screen Grid and the third is Suppressor Grid.
The Suppressor Grid is connected to the Cathode and serves to Suppress the effects of Secondary Emission.
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Friday, July 18, 2008
The Important Thermionic Emitters and its Properties.
The substance used for Electron Emission is known as an Emitter.An Emitter should have the following Properties.
01)High Melting Point:-
As Electron Emission takes place at very High Temperatures,therefore,the substance used as Emitter should have High Melting Point.
02)Low Work Function:-
The substance selected as an Emitter should have Low Work Function so that Electron Emission takes place by applying small amount of Heat Energy.
03)High Mechanical Strength:-
The Emitter should have High Mechanical Strength to withstand the Bombardment of Positive Ions.
Important Thermionic Emitters:-
The High Temperatures needed for satisfactory Thermionic Emission in Vacuum Tubes limit the number of suitable Emitters to such substances as follows.
01)Tungsten:-
It was the earliest material used as a Cathode and has a slightly Higher Work Function.Below are the Important Factors in its Favour.
A)High Melting Point.
B)Greater Mechanical Strength.
C)Longer Life.
Besides this,Tungsten has following Disadvantages:-
A)High Operating Temperature.
B)High Work Function.
C)Low Emission Efficiency.
Tungsten can be used in application involving Voltage exceeding 5kV.
02)Thoriated Tungsten:-
A mixture of two metals may have a Lower Work Function than either of the pure metal alone.Thus,a Tungsten Emitter with a small quantity of Thorium has a Work Function of 2.63 eV,compared with 3.4 eV for Thorium and 4.52 eV for Tungsten.
At the same time,Thoriated Tungsten provides Thermionic Emission at Lower Temperature with consequent reduction in the heating power required.Thoriated Tungsten Emitters are used for Intermediate Power Tubes at Voltage between 500 to 5000 Volts.
03)Oxide-Coated Cathode:-
This type of Cathode consist of a Nickel ribbon coated with Barium and Strontium Oxides.The Oxide-Coated Cathode has Low Work function,operates at comparatively Low Temperature and has Higher Emission Efficiency.
However,the principle limitation of Oxide-Coated Cathode is that it can not withstand High Voltages.Therefore,it is mostly used in Receiving Tubes or where Voltage involved do not exceed 1000 Volts.
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01)High Melting Point:-
As Electron Emission takes place at very High Temperatures,therefore,the substance used as Emitter should have High Melting Point.
02)Low Work Function:-
The substance selected as an Emitter should have Low Work Function so that Electron Emission takes place by applying small amount of Heat Energy.
03)High Mechanical Strength:-
The Emitter should have High Mechanical Strength to withstand the Bombardment of Positive Ions.
Important Thermionic Emitters:-
The High Temperatures needed for satisfactory Thermionic Emission in Vacuum Tubes limit the number of suitable Emitters to such substances as follows.
01)Tungsten:-
It was the earliest material used as a Cathode and has a slightly Higher Work Function.Below are the Important Factors in its Favour.
A)High Melting Point.
B)Greater Mechanical Strength.
C)Longer Life.
Besides this,Tungsten has following Disadvantages:-
A)High Operating Temperature.
B)High Work Function.
C)Low Emission Efficiency.
Tungsten can be used in application involving Voltage exceeding 5kV.
02)Thoriated Tungsten:-
A mixture of two metals may have a Lower Work Function than either of the pure metal alone.Thus,a Tungsten Emitter with a small quantity of Thorium has a Work Function of 2.63 eV,compared with 3.4 eV for Thorium and 4.52 eV for Tungsten.
At the same time,Thoriated Tungsten provides Thermionic Emission at Lower Temperature with consequent reduction in the heating power required.Thoriated Tungsten Emitters are used for Intermediate Power Tubes at Voltage between 500 to 5000 Volts.
03)Oxide-Coated Cathode:-
This type of Cathode consist of a Nickel ribbon coated with Barium and Strontium Oxides.The Oxide-Coated Cathode has Low Work function,operates at comparatively Low Temperature and has Higher Emission Efficiency.
However,the principle limitation of Oxide-Coated Cathode is that it can not withstand High Voltages.Therefore,it is mostly used in Receiving Tubes or where Voltage involved do not exceed 1000 Volts.
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Thursday, July 17, 2008
How you can construct Cathode?
The substance used for Electron Emission is known as Emitter or Cathode.
The Cathode is heated in an evacuated space to emit Electrons.
As Cathode is sealed in Vacuum,therefore,the most convenient way to heat it is Electrically.
The heating processes may be done by two methods.The Thermionic Cathode are divided into two types,
01)Directly Heated Cathode
02)Indirectly Heated Cathode
01)Directly Heated Cathode:-
In this type,the Cathode consists of Oxide-Coated Nickel ribbon,which is known as "Filament".The heating Current is Directly passed through this Nickel ribbon which Emits the Electrons.
The Directly Heated Cathode is more efficient in converting heating power into Thermionic Emission.Therefore,it is generally used in Power Tubes that needs large amount of Emission and in small tubes operated from Batteries,where efficiency and quick heating are important.
The principal limitation of this type of Cathode is that any variation in heater Voltage affects the Electron Emission and this produce "Hum" in the Circuit.
02)Indirectly Heated Cathode:-
In this type,the Cathode consists of a thin metal sleeve coated with Barium and Strontium Oxides.A Filament or heater is enclosed within the sleeve and insulated from it.There is no Electric Connection between the heater and the Cathode.
The heating Current is passed through the Heater and the Cathode is heated indirectly through heat transfer from the heater element.
Advantages of Indirectly Heated Cathode:-
01)As Cathode is completely separated from the heating circuit,therefore,it can be readily connected to any desired potential as needed,independent of the heater potential.
02)Because of relatively large mass of Cylindrical Cathode,it takes time to heat or cool and as such does not introduce "Hum" due to heater Voltage Fluctutions.
03)a.c. can be used in the heater Circuit to simplify the Power requirement.
What is mean by Filament.
It is the thin wire,denotes the element through which the Cathode heating Current flows.In case of Directly Heated type,Cathode is itself the Filament.Whereas,heater is the Filament in Indirectly Heated Type.
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The Cathode is heated in an evacuated space to emit Electrons.
As Cathode is sealed in Vacuum,therefore,the most convenient way to heat it is Electrically.
The heating processes may be done by two methods.The Thermionic Cathode are divided into two types,
01)Directly Heated Cathode
02)Indirectly Heated Cathode
01)Directly Heated Cathode:-
In this type,the Cathode consists of Oxide-Coated Nickel ribbon,which is known as "Filament".The heating Current is Directly passed through this Nickel ribbon which Emits the Electrons.
The Directly Heated Cathode is more efficient in converting heating power into Thermionic Emission.Therefore,it is generally used in Power Tubes that needs large amount of Emission and in small tubes operated from Batteries,where efficiency and quick heating are important.
The principal limitation of this type of Cathode is that any variation in heater Voltage affects the Electron Emission and this produce "Hum" in the Circuit.
02)Indirectly Heated Cathode:-
In this type,the Cathode consists of a thin metal sleeve coated with Barium and Strontium Oxides.A Filament or heater is enclosed within the sleeve and insulated from it.There is no Electric Connection between the heater and the Cathode.
The heating Current is passed through the Heater and the Cathode is heated indirectly through heat transfer from the heater element.
Advantages of Indirectly Heated Cathode:-
01)As Cathode is completely separated from the heating circuit,therefore,it can be readily connected to any desired potential as needed,independent of the heater potential.
02)Because of relatively large mass of Cylindrical Cathode,it takes time to heat or cool and as such does not introduce "Hum" due to heater Voltage Fluctutions.
03)a.c. can be used in the heater Circuit to simplify the Power requirement.
What is mean by Filament.
It is the thin wire,denotes the element through which the Cathode heating Current flows.In case of Directly Heated type,Cathode is itself the Filament.Whereas,heater is the Filament in Indirectly Heated Type.
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Wednesday, July 16, 2008
Which are the Important Methods for obtaining Electron Emission?
From my previous post,you come to know about "Emission of Electrons".This Electron Emission can be classified in four different types.
The details about that four types are as below.
The External Energy which is used for Emission of Electrons,may come from variety of sources such as Heat Energy,Energy stored in Electric Field,Light Energy or Kinetic Energy of the Electric Charges Bombarding the Metal Surface.
Accordingly,there are four principle methods of obtaining Electron Emission from the Surface of Metal.
01)Secondary Emission:-
When High-Speed Electrons suddenly strike a Metal Surface,they may give some or all of their Kinetic Energy to the Free Electrons in the Metal.
If the Energy of the striking Electrons is sufficient,it may cause Free Electrons to leave from the Metal Surface.This phenomenon is known as Secondary Emission.
The Electrons that strike the Metal are called Primary Electrons while the Emitted Electrons are known as Secondary Electrons.
02)Thermionic Emission:-
In this method,the Metal is Heated about 2500 Degree Centigrade to enable the Free Electrons to leave the Metal Surface.The number of Electrons emitted depends upon the Temperature.Greater the Emission of Electrons,with Higher the Temperature.This type of Emission is employed in Vacuum Tubes.
03)Field Emission:-
A strong Electric Field is applied at the Metal Surface which pulls the Free Electrons out of Metal because of the attraction of Positive Field.Very intense Electric Field is required to produce Field Emission.
Usually,a Voltage of the order of million volts per centimeter distance between the Emitting Surface and the Positive Conductor is necessary to cause Field Emission.
Field Emission can obtained at Room Temperature,that's why,some time it is called as Cold Cathode Emission or Auto Electronic Emission.
04)Photo-Electric Emission:-
In this method,the Energy of Light falling upon the Metal Surface is Transferred to the Free Electrons within the Metal to enable them to leave the Surface.
The greater the intensity of Light Beam falling on the Metal Surface, greater is the Photo-Electric Emission.Photo-Electric Emission is utilised in Photo Tubes which form the basic of Television and Sound Films.
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The details about that four types are as below.
The External Energy which is used for Emission of Electrons,may come from variety of sources such as Heat Energy,Energy stored in Electric Field,Light Energy or Kinetic Energy of the Electric Charges Bombarding the Metal Surface.
Accordingly,there are four principle methods of obtaining Electron Emission from the Surface of Metal.
01)Secondary Emission:-
When High-Speed Electrons suddenly strike a Metal Surface,they may give some or all of their Kinetic Energy to the Free Electrons in the Metal.
If the Energy of the striking Electrons is sufficient,it may cause Free Electrons to leave from the Metal Surface.This phenomenon is known as Secondary Emission.
The Electrons that strike the Metal are called Primary Electrons while the Emitted Electrons are known as Secondary Electrons.
02)Thermionic Emission:-
In this method,the Metal is Heated about 2500 Degree Centigrade to enable the Free Electrons to leave the Metal Surface.The number of Electrons emitted depends upon the Temperature.Greater the Emission of Electrons,with Higher the Temperature.This type of Emission is employed in Vacuum Tubes.
03)Field Emission:-
A strong Electric Field is applied at the Metal Surface which pulls the Free Electrons out of Metal because of the attraction of Positive Field.Very intense Electric Field is required to produce Field Emission.
Usually,a Voltage of the order of million volts per centimeter distance between the Emitting Surface and the Positive Conductor is necessary to cause Field Emission.
Field Emission can obtained at Room Temperature,that's why,some time it is called as Cold Cathode Emission or Auto Electronic Emission.
04)Photo-Electric Emission:-
In this method,the Energy of Light falling upon the Metal Surface is Transferred to the Free Electrons within the Metal to enable them to leave the Surface.
The greater the intensity of Light Beam falling on the Metal Surface, greater is the Photo-Electric Emission.Photo-Electric Emission is utilised in Photo Tubes which form the basic of Television and Sound Films.
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Tuesday, July 15, 2008
What is mean by Electron Emission?
At Room Temperature,the Thermal Energy in the Conductor is adequate to break the bonds of the Valence Electrons and leave them unattached to any one Nucleus.These Unbound Electrons moves at random within the Conductor and are known as Free Electrons.
If an Electric Field is applied across the Conductor,these Free Electrons move through the Conductor in an orderly manner,thus constituting Electric Current.
Many Electronic Devices depend for their operation on the movement of Electrons in an evacuated space.For this purpose,the Free Electrons must be ejected from the surface of Metallic Conductor by supplying sufficient Energy from some external source.This known as Electron Emission.
Electron Emission:-
Metals are used for Electron Emission,as they have many Free Electrons.If a piece of Metal is investigated at Room Temperature,the random motion of Free Electrons is within surface of the metal.
These Electrons are free only to the extent that they may transfer from one Atom to another within the Metal Surface.But they could not leave the Metal Surface to provide Electron Emission.
This is due to the Metallic Surface offers a barrier to Free Electrons and is known as Surface Barrier.
If we increase the Kinetic Energy of Free Electrons,by giving sufficient external Energy,the Electron will cross over the surface barrier to leave the Metal.
The amount of additional Energy required to emit an Electron from a Metallic Surface is known as Work Function of the Metal.
The Work Function of pure metal varies roughly from 2 to 6 eV.
It depends upon the nature of the Metal,its purity and the conditions of its surface.It may be noted that it is desirable that the metal used for
Electron Emission should have Low Work Function,so that a small amount of Energy is required to cause Emission of Electrons.
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If an Electric Field is applied across the Conductor,these Free Electrons move through the Conductor in an orderly manner,thus constituting Electric Current.
Many Electronic Devices depend for their operation on the movement of Electrons in an evacuated space.For this purpose,the Free Electrons must be ejected from the surface of Metallic Conductor by supplying sufficient Energy from some external source.This known as Electron Emission.
Electron Emission:-
Metals are used for Electron Emission,as they have many Free Electrons.If a piece of Metal is investigated at Room Temperature,the random motion of Free Electrons is within surface of the metal.
These Electrons are free only to the extent that they may transfer from one Atom to another within the Metal Surface.But they could not leave the Metal Surface to provide Electron Emission.
This is due to the Metallic Surface offers a barrier to Free Electrons and is known as Surface Barrier.
If we increase the Kinetic Energy of Free Electrons,by giving sufficient external Energy,the Electron will cross over the surface barrier to leave the Metal.
The amount of additional Energy required to emit an Electron from a Metallic Surface is known as Work Function of the Metal.
The Work Function of pure metal varies roughly from 2 to 6 eV.
It depends upon the nature of the Metal,its purity and the conditions of its surface.It may be noted that it is desirable that the metal used for
Electron Emission should have Low Work Function,so that a small amount of Energy is required to cause Emission of Electrons.
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Sunday, July 13, 2008
Some unbelievable uses of Electronics Engineering.
The Branch of Engineering which deals with Current Conduction through a Vacuum or Gas or Semiconductor is known as Electronics.
Electronics mainly deals with Electronics Devices and their utilization.Such Devices have valuable properties which enable them to function and behave as the friend of Human today.
Electronics has gained much importance due to its numerous application in Industry.
The Electronics Devices are capable of performing various functions.Out of that the main functions are as below.
01)Amplification:-
The process of raising the Strength of Weak Signals to Strong Signals is known as Amplification.An Amplifier,is used in Radio-Set where the Weak Signals are Amplified so that it can be heard loudly.
02)Rectification:-
The conversion of Alternative Current (a.c.) into Direct Current (d.c.) is called Rectification.Electronics Device can convert a.c.Power into d.c. Power with very high efficiency.This d.c. supply can be used for Charging Storage Batteries,Field Supply of D.C.Generators,Electroplating etc..
03)Conversion of Light into Electricity:-
This Conversion of Light into Electricity is known as Photo-Electricity.Photo-Electric Devices are used in Sound Recording on Motion Pictures etc..
04)Generation:-
Electronics Devices can convert d.c. Power into a.c. Power of any Frequency.When performing this function,they are known as Oscillators.Electronics High Frequency Heating is used for Annealing and Hardening.
05)Control:-
Electronics Devices find wide applications in Automatic Control.For example,Speed of Motor,Voltage across Refrigerator etc.. can be Automatically Controlled with the help of Such Electronics Devices.
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What is Thermistors means?
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Electronics mainly deals with Electronics Devices and their utilization.Such Devices have valuable properties which enable them to function and behave as the friend of Human today.
Electronics has gained much importance due to its numerous application in Industry.
The Electronics Devices are capable of performing various functions.Out of that the main functions are as below.
01)Amplification:-
The process of raising the Strength of Weak Signals to Strong Signals is known as Amplification.An Amplifier,is used in Radio-Set where the Weak Signals are Amplified so that it can be heard loudly.
02)Rectification:-
The conversion of Alternative Current (a.c.) into Direct Current (d.c.) is called Rectification.Electronics Device can convert a.c.Power into d.c. Power with very high efficiency.This d.c. supply can be used for Charging Storage Batteries,Field Supply of D.C.Generators,Electroplating etc..
03)Conversion of Light into Electricity:-
This Conversion of Light into Electricity is known as Photo-Electricity.Photo-Electric Devices are used in Sound Recording on Motion Pictures etc..
04)Generation:-
Electronics Devices can convert d.c. Power into a.c. Power of any Frequency.When performing this function,they are known as Oscillators.Electronics High Frequency Heating is used for Annealing and Hardening.
05)Control:-
Electronics Devices find wide applications in Automatic Control.For example,Speed of Motor,Voltage across Refrigerator etc.. can be Automatically Controlled with the help of Such Electronics Devices.
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What is Thermistors means?
What is mean by Hygrometer?
What is Tachometer Generators?
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