MCQS | With fall of temperature, the forbidden energy gap of a semiconductor

Question :- A p-type semiconductor is:

1.negatively charged

2.positively charged

3.uncharged

4.None of the these

Question :- Bonds in a semiconductor :

1.trivalent

2.covalent

3.bivalent

4.monovalent

Question :- Crystal diode is:

1.amplifying device

2.fluctuating device

3. non-linear device

4.linear device

Question :- Energy bands in solids are a consequence of:

1.Ohm’s Law

2.Pauli’s exclusion principle

3.Bohr’s theory

4.Heisenberg’s uncertainty principle

Question :- In a common base amplifier the phase difference between the input signal voltage and output voltage is :

1. π/2

2.0

3.π/4

4.π

Question :- In a p-type semiconductor, current conduction is by:

1.atoms

2.holes

3.electrons

4.protons

Question :- In binary system III represents:

1.1

2.3

3.7

4.100

Question :- In full wave rectifier, input a.c. current has a frequency v. The output frequency of current is :

1.V/2

2.V

3.2V

4.None

Question :- In intrinsic semiconductor at room temperature, the number of electrons and holes are:

1.equal

2.unequal

3.infinite

4.zero

Question :- In semi conductor which are responsible for conduction:

1.only electron

2.electron and hole both

3.only hole

4.None of the above

Question :- In semi conductor, at room temperature :

1.the valence bond is partially empty and the conduction band is partially filled

2.the valence bond is partially empty and the conduction band is partially filled

3. the valence band is completely filled

4.None of the above

Question :- In the middle of the depletion layer of a reverse biased p-n junction, the:

1.electric field is zero

2. potential is maximum

3.electric field is maximum

4.potential zero.

Question :- Main function of a transistor is to :

1.rectify

2.simplify

3.amplify

4.All the above

Question :- n reverse biasing:

1.large amount of current flows

2.no current flows

3.potential barrier across junction increases

4.depletion layer resistance increases

Question :- Number of electrons in the valence shell of a semiconductor is:

1.1

2.2

3.3

4.4

Question :- On applying reverse bias to a junction diode, it:

1.lowers the potential barrier

2. raise the potential barrier

3.increases the majority carrier current

4.increases the minority carrier current

Question :- On heating, resistance of semiconductors:

1.decreases

2.increases

3.remains same

4.first increases then decreases

Question :- p-n junction diode can be used as:

1.amplifier

2.oscillator

3.detector

4.modulator

Question :- Semiconductors of both p-type and n-type are produced by:

1.ionic solids

2.covalent solids

3.metallic solids

4.molecular solids

Question :- The material most commonly used to manufacture electronic solid state devices is :

1.copper

2.silicon

3.germanium

4.aluminium

Question :- The part of a transistor which is heavily doped to produce a large number of majority carriers is :

1. base

2.emitter

3.collector

4.None of the these

Question :- The relation between number of free electrons (n) in a semiconductor and temperature (T) is given by:

1.n ∝ T

2.n ∝ T²

3.n ∝ T1/2

4.n ∝ T3/2

Question :- To obtain electrons as majority charge carriers in a semiconductors the impurity mixed is:

1.monovalent

2.divalent

3.trivalent

4.pentavalent

Question :- To obtain p-type silicon semiconductor, we need to dope pure silicon with:

1.aluminium

2.phosphorus

3.oxygen

4.germanium

Question :- What is the number of possible crystal systems?

1.5

2.7

3.14

4.16

Question :- Winch of the following gate is not an universal gate?

1.OR

2.NOT

3.AND

4.NAND

Question :- With fall of temperature, the forbidden energy gap of a semiconductor

1.increases

2.decreases

3.sometimes increases and sometimes decreases

4.remains unchanged

Question :- Zener diode is used for:

1.Zener diode is used for:

2.amplification

3.stabilisation

4.rectification