ICS Part 2 Physics Chapter 18 Short Questions Preparation

Question # 1

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 # 2

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 # 3

Explain why an ordinary Silicon diode does not emit light.

Ans 1: Ordinary silicon is opaque to light,So it does not emit visible light.It emits infrared light.To emit light ,gallium arsenide or gallium arsenide photodiode are used as semiconductor.

Question # 4

How is p-n junction formed?

Ans 1: A p-n junction is formed when a crystal of germanium or silicon is grown in such a way that is its one half is doped with a trivalent impurity and the other half with a pentavalent impurity.

Question # 5

Give any two characteristics of operational amplifier.

Ans 1: Input Resistance: It is the resistance between the + and - input of the amplifier,Whose value is of the order of several mega ohms.
Output resistance:It is the resistance between the output terminal and ground.Its value is only a few ohms.

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

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 # 8

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 # 9

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 # 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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ICS Part 2 Physics Chapter 18 Short Questions Preparation

12th Class PhysicsShort Questions Preparation

12th Class Physics Chapter Wise Preparation

Online Short Questions For Chapter 7 "ICS Part 2 Physics Chapter 18 Short Questions Preparation "

Physics - ICS Part 2 Physics Chapter 18 Short Questions Preparation

Give four application or uses of photodiode?

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

Explain why an ordinary Silicon diode does not emit light.

How is p-n junction formed?

Give any two characteristics of operational amplifier.

How the current flows in forward and reverse biased diode?

How the normal operation of transistor is achieved?

Define Depletion region?

What is principle of vital ground?

Differentiate between the forward biased and the reserve biase.

Prepare Complete Set Wise Questions For Chapter 7 "ICS Part 2 Physics Chapter 18 Short Questions Preparation "

Set 1

Set 2

Set 3

ICS Part 2 Physics Chapter 18 Short Questions Preparation - Set 1

Give four application or uses of photodiode?

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

Explain why an ordinary Silicon diode does not emit light.

How is p-n junction formed?

Give any two characteristics of operational amplifier.

How the current flows in forward and reverse biased diode?

How the normal operation of transistor is achieved?

Define Depletion region?

What is principle of vital ground?

Differentiate between the forward biased and the reserve biase.

ICS Part 2 Physics Chapter 18 Short Questions Preparation - Set 2

How the normal operation of transistor is achieved?

Define logic system and logic gates.

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

What is photovoltaic cell?Discuss its working?

Give any two characteristics of operational amplifier.

What is the effect of forward biased and reverse biasing of a diode on the width of depletion region?

What is semiconductor diode?

Define current of gain of a transistor

How is the XOR gate so called?

Give four application or uses of photodiode?

ICS Part 2 Physics Chapter 18 Short Questions Preparation - Set 3

How the current flows in forward and reverse biased diode?

How does the motion of an electron in n type substance differ from the motion of holes in a p type substance?

Define Depletion region?

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

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

Give two applications of gated in control system.

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

Define logic system and logic gates.

What is photodiode?Write down its two main applications.

What is photovoltaic cell?Discuss its working?

ICS Part 2 Physics Chapter 18 Short Questions Preparation

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