ICS Part 2 Physics Chapter 18 Short Questions Preparation

Question # 1

Why charge carriers are not present in the depletion region?

Ans 1: This is due to the fact when an electron from an n region diffuses into the p-region,it leaves behind a positive ion.When this electron recombines with the hole in the p-region,a negative ion is formed,So no charge carrier are available in this region,though it contains immobile positive and negative ions.

Question # 2

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 # 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

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 # 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

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 # 7

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 # 8

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 # 9

What is photovoltaic cell?Discuss its working?

Ans 1: It consists of a thick n type region covered by a thin p-layer type.When exposed to light,it absorbs photon which generated electron-hole pairs.The electric field at the junction moves electron and holes and a current flow through the external circuit.And this current is directly proportional to the intensity of light.

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

Why charge carriers are not present in the depletion region?

Define Depletion region?

Why is the photodiode operated in reverse biased state?

Define current of gain of a transistor

What do LED and LASER stand for?

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

Define logic system and logic gates.

Write a note on LED.

What is photovoltaic cell?Discuss its working?

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

Why charge carriers are not present in the depletion region?

Define Depletion region?

Why is the photodiode operated in reverse biased state?

Define current of gain of a transistor

What do LED and LASER stand for?

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

Define logic system and logic gates.

Write a note on LED.

What is photovoltaic cell?Discuss its working?

Differentiate between the forward biased and the reserve biase.

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

Define logic system and logic gates.

What is photovoltaic cell?Discuss its working?

Define Depletion region?

Give two applications of gated in control system.

What is AND Gate?

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

What is OP-GATE?

Define Open Loop gain of operational amplifier.

What is the potential barrier?What is the value of potential barrier of SI and Ge?

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

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

Give any two characteristics of operational amplifier.

Explain why an ordinary Silicon diode does not emit light.

What is OP-GATE?

What is photodiode?Write down its two main applications.

Give four application or uses of photodiode?

Differentiate between the forward biased and the reserve biase.

What is photovoltaic cell?Discuss its working?

What is the potential barrier?What is the value of potential barrier of SI and Ge?

How the normal operation of transistor is achieved?

Give two applications of gated in control system.

ICS Part 2 Physics Chapter 18 Short Questions Preparation

12th Class Physics
Short Questions Preparation