2nd Year Physics Chapter 18 Online Preparation (Electronics)

Online Short Questions For Chapter 7 "12th Class Physics Chapter 7 Short Questions Preparation "

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Physics - 12th Class Physics Chapter 7 Short Questions Preparation

Question # 1

Why the base current is transistor is very small?

Ans 1: Base is very thin so a number of electrons attracted by collector and very few enter into the base.And base current is very small.

Question # 2

What is principle of vital ground?

Ans 1: In an operational amplifier ,if the non inverting terminal is grounded by the concept of virtual ground the inverting terminal is also at ground potential though there is no physical connection between the inverting terminal and the ground,This is the principle of virtual ground.

Question # 3

Why is the photodiode operated in reverse biased state?

Ans 1: Photodiode is used for the detection of light.So it is used in reverse biased state.Reverse current increase with the intensity of incident light.When no light incidents,then reverse current will be negligible.

Question # 4

Write a note on LED.

Ans 1: Light emitting diode are made from the special semiconductor such as gallium arsenide and gallium arsenide phosphide in which the potential barrier between p and n side is such that when electrons combines with a hole during forward biased conduction,a photon of visible light is emitted.
LED are used in 7-segment display,small light sources etc.

Question # 5

Why the biasing requirement of the junction of a transistor for its normal operation?

Ans 1: For the normal operation the base emitter junction of transistor is forward biased and collector base junction is reverse biased.

Question # 6

What is the role of potential barrier in a diode?How it is formed in diode?

Ans 1: At the formation of pn-junction ,the free electrons in n-region because of their random motion diffuse into the p-region,.As a result of this diffusion a region is formed around the junction consisting of positive and negative ions,Due to charge on these ions a potential difference develops across the depletion region,This potential difference is called potential barrier,stops further diffusion of electron into the p-region.

Question # 7

What is OP-GATE?

Ans 1: OR-GATE implements the logic of OR operation.It has two or more inputs and a single output.Its output will be zero only when all the inputs are zero.

Question # 8

Give two applications of gated in control system.

Ans 1: Gates are widely used in control system.They control the function of the system by monitoring some physical parameters such as temperature ,pressure or some other physical quantity of the system,Sensors are required to operate gates.

Question # 9

Give four application or uses of photodiode?

Ans 1: It is used as
1. Detection of both visible and invisible radiations.
2. Logic circuits
3. Automatic switching
4. Optical communication equipment

Question # 10

Define Open Loop gain of operational amplifier.

Ans 1: The ratio of output voltage to voltage difference between non -inverting and inverting inputs ,when there is no external connection between the input and output is called open loop gain of operational amplifier.

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Prepare Complete Set Wise Questions For Chapter 7 "12th Class Physics Chapter 7 Short Questions Preparation "

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Set 2

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Set 3

10 Questions
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12th Class Physics Chapter 7 Short Questions Preparation - Set 1

Question # 1

Why the base current is transistor is very small?

Ans 1: Base is very thin so a number of electrons attracted by collector and very few enter into the base.And base current is very small.

Question # 2

What is principle of vital ground?

Ans 1: In an operational amplifier ,if the non inverting terminal is grounded by the concept of virtual ground the inverting terminal is also at ground potential though there is no physical connection between the inverting terminal and the ground,This is the principle of virtual ground.

Question # 3

Why is the photodiode operated in reverse biased state?

Ans 1: Photodiode is used for the detection of light.So it is used in reverse biased state.Reverse current increase with the intensity of incident light.When no light incidents,then reverse current will be negligible.

Question # 4

Write a note on LED.

Ans 1: Light emitting diode are made from the special semiconductor such as gallium arsenide and gallium arsenide phosphide in which the potential barrier between p and n side is such that when electrons combines with a hole during forward biased conduction,a photon of visible light is emitted.
LED are used in 7-segment display,small light sources etc.

Question # 5

Why the biasing requirement of the junction of a transistor for its normal operation?

Ans 1: For the normal operation the base emitter junction of transistor is forward biased and collector base junction is reverse biased.

Question # 6

What is the role of potential barrier in a diode?How it is formed in diode?

Ans 1: At the formation of pn-junction ,the free electrons in n-region because of their random motion diffuse into the p-region,.As a result of this diffusion a region is formed around the junction consisting of positive and negative ions,Due to charge on these ions a potential difference develops across the depletion region,This potential difference is called potential barrier,stops further diffusion of electron into the p-region.

Question # 7

What is OP-GATE?

Ans 1: OR-GATE implements the logic of OR operation.It has two or more inputs and a single output.Its output will be zero only when all the inputs are zero.

Question # 8

Give two applications of gated in control system.

Ans 1: Gates are widely used in control system.They control the function of the system by monitoring some physical parameters such as temperature ,pressure or some other physical quantity of the system,Sensors are required to operate gates.

Question # 9

Give four application or uses of photodiode?

Ans 1: It is used as
1. Detection of both visible and invisible radiations.
2. Logic circuits
3. Automatic switching
4. Optical communication equipment

Question # 10

Define Open Loop gain of operational amplifier.

Ans 1: The ratio of output voltage to voltage difference between non -inverting and inverting inputs ,when there is no external connection between the input and output is called open loop gain of operational amplifier.

Submit

12th Class Physics Chapter 7 Short Questions Preparation - Set 2

Question # 1

Define logic system and logic gates.

Ans 1: A digital system deals with the quantities or variable which have only two discrete values or state.
The electronic circuits which implements the various logic operation are known as logic gates.

Question # 2

What is the net charge on a n-type or p-type substance?

Ans 1: Since they are electrically neutral substance,So the net charge on them is zero.

Question # 3

Define Open Loop gain of operational amplifier.

Ans 1: The ratio of output voltage to voltage difference between non -inverting and inverting inputs ,when there is no external connection between the input and output is called open loop gain of operational amplifier.

Question # 4

Define Depletion region?

Ans 1: A region in a semiconductor device,usually at the junction of p-type and n-type materials ,in which there is neither an excess of electrons nor of holes is called depletion region,It charge less region.

Question # 5

How the normal operation of transistor is achieved?

Ans 1: For the normal operation the base emitter junction of transistor is forward biased and collector base junction is reverse.
In a common emitter amplifier ,input signal is applied between base and emitter and output signal is taken across collector and emitter,Similarly emitter base junction is forward biased and collector base junction is reverse biased.

Question # 6

How the current flows in forward and reverse biased diode?

Ans 1: In forward biasing,the external potential difference supplies energy to free electrons in n-region and holes in p-region to overcome the potential barrier,a current of the orderof a few milli-amperes begins to flow across the pn junction.
In reverse biasing ,no current flow due to the majority charge carrier,However a very small current of the order of of few micro amperes flow across the junction due to minority charge carriers.It is also known as reverse current or leakage current.

Question # 7

Why the biasing requirement of the junction of a transistor for its normal operation?

Ans 1: For the normal operation the base emitter junction of transistor is forward biased and collector base junction is reverse biased.

Question # 8

Why the base current is transistor is very small?

Ans 1: Base is very thin so a number of electrons attracted by collector and very few enter into the base.And base current is very small.

Question # 9

Write a note on LED.

Ans 1: Light emitting diode are made from the special semiconductor such as gallium arsenide and gallium arsenide phosphide in which the potential barrier between p and n side is such that when electrons combines with a hole during forward biased conduction,a photon of visible light is emitted.
LED are used in 7-segment display,small light sources etc.

Question # 10

Differentiate between the forward biased and the reserve biase.

Ans 1: When p side is positive and n-side is negative,the diode is forward biased.The width of depletion region reduces to which more current is allowed to flow across the junction.The forward resistance is few ohms.
Ans 2: When p side is negative and n side is positive,the diode is reserved biased.The width of depletion region is increased and a very small current flows across the junction due to flow of minority charges carriers,The resistance offered by the diode is several mega ohms.

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12th Class Physics Chapter 7 Short Questions Preparation - Set 3

Question # 1

Define current of gain of a transistor

Ans 1: The ratio of output current to input current is called current gain of a transistor.The ratio of collector current to base current is called current gain of a transistor.

Question # 2

Why the base current is transistor is very small?

Ans 1: Base is very thin so a number of electrons attracted by collector and very few enter into the base.And base current is very small.

Question # 3

How the current flows in forward and reverse biased diode?

Ans 1: In forward biasing,the external potential difference supplies energy to free electrons in n-region and holes in p-region to overcome the potential barrier,a current of the orderof a few milli-amperes begins to flow across the pn junction.
In reverse biasing ,no current flow due to the majority charge carrier,However a very small current of the order of of few micro amperes flow across the junction due to minority charge carriers.It is also known as reverse current or leakage current.

Question # 4

Why the biasing requirement of the junction of a transistor for its normal operation?

Ans 1: For the normal operation the base emitter junction of transistor is forward biased and collector base junction is reverse biased.

Question # 5

What do LED and LASER stand for?

Ans 1: LED stands for light emitting diode..
Laser stands for light amplification stimulated emission radiation .

Question # 6

Define logic system and logic gates.

Ans 1: A digital system deals with the quantities or variable which have only two discrete values or state.
The electronic circuits which implements the various logic operation are known as logic gates.

Question # 7

What is semiconductor diode?

Ans 1: p-n junction is called semiconductor diode.

Question # 8

The anode of a diode is 0.2V positive with respect to the cathode,It it forward biased?

Ans 1: Yes when anode is 0.2V positive with respect to cathode,it is forward biased.But the value of potential barrier for germanium is 0.3 V and for silicon is 0.7 V.Therefore there will be no conduction of current.

Question # 9

Write a note on LED.

Ans 1: Light emitting diode are made from the special semiconductor such as gallium arsenide and gallium arsenide phosphide in which the potential barrier between p and n side is such that when electrons combines with a hole during forward biased conduction,a photon of visible light is emitted.
LED are used in 7-segment display,small light sources etc.

Question # 10

Differentiate between the forward biased and the reserve biase.

Ans 1: When p side is positive and n-side is negative,the diode is forward biased.The width of depletion region reduces to which more current is allowed to flow across the junction.The forward resistance is few ohms.
Ans 2: When p side is negative and n side is positive,the diode is reserved biased.The width of depletion region is increased and a very small current flows across the junction due to flow of minority charges carriers,The resistance offered by the diode is several mega ohms.

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12th Class Physics Ch 18 Preparation

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2nd Year Physics Chapter 18 Online Preparation (Electronics)

Online Short Questions For Chapter 7 "12th Class Physics Chapter 7 Short Questions Preparation "

Physics - 12th Class Physics Chapter 7 Short Questions Preparation

Why the base current is transistor is very small?

What is principle of vital ground?

Why is the photodiode operated in reverse biased state?

Write a note on LED.

Why the biasing requirement of the junction of a transistor for its normal operation?

What is the role of potential barrier in a diode?How it is formed in diode?

What is OP-GATE?

Give two applications of gated in control system.

Give four application or uses of photodiode?

Define Open Loop gain of operational amplifier.

Prepare Complete Set Wise Questions For Chapter 7 "12th Class Physics Chapter 7 Short Questions Preparation "

Set 1

Set 2

Set 3

12th Class Physics Chapter 7 Short Questions Preparation - Set 1

Why the base current is transistor is very small?

What is principle of vital ground?

Why is the photodiode operated in reverse biased state?

Write a note on LED.

Why the biasing requirement of the junction of a transistor for its normal operation?

What is the role of potential barrier in a diode?How it is formed in diode?

What is OP-GATE?

Give two applications of gated in control system.

Give four application or uses of photodiode?

Define Open Loop gain of operational amplifier.

12th Class Physics Chapter 7 Short Questions Preparation - Set 2

Define logic system and logic gates.

What is the net charge on a n-type or p-type substance?

Define Open Loop gain of operational amplifier.

Define Depletion region?

How the normal operation of transistor is achieved?

How the current flows in forward and reverse biased diode?

Why the biasing requirement of the junction of a transistor for its normal operation?

Why the base current is transistor is very small?

Write a note on LED.

Differentiate between the forward biased and the reserve biase.

12th Class Physics Chapter 7 Short Questions Preparation - Set 3

Define current of gain of a transistor

Why the base current is transistor is very small?

How the current flows in forward and reverse biased diode?

Why the biasing requirement of the junction of a transistor for its normal operation?

What do LED and LASER stand for?

Define logic system and logic gates.

What is semiconductor diode?

The anode of a diode is 0.2V positive with respect to the cathode,It it forward biased?

Write a note on LED.

Differentiate between the forward biased and the reserve biase.

12th Class Physics Ch 18 Preparation

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