electronics (final)

7/30/2019 Electronics (Final)

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Section

df Question Option 1 Option 2

(1) (2) (3) (4)

1

In which of the folloiwng

application vacuum tubes

are still in use?

Radio Receiver Radio Transmitters

2Field effect transister

have?

Very high input

resistance Low input resistance

3

Class A amplifier is used

when? No phase investigationis required DC voltage is to beamplified

4

Cross-over distortion in

class - B push pull

amplifier is eliminated by?

Operating amplifier as

Class A


Class C

5

Which of the following

transistor are affected by

static electricity?

UJT NPN

6

An ideal voltage Amplifier

should have?

Input resistance =0,

Output resistance =0

Input resistance =0,

Output resistance =Infinity

7Decibel is defined in

terms of?

Voltage Ratio Current ratio

8Vacuum tubes can be

used in?

Amplifier Rectifiers

9

FET is advantageous in

comparision with BJT

because of?

High input impedence High noise

10

Gain of amplifier will be

more affected by changein transistor parameter in

case of?

Negative feedback Positive feedback

11

By heating a material the

conductivity of the

material?

Increases Decreases

c


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12

An oscillator that user a

tapped coil in the LC

tuned circuit is the?

Pierce oscillator Arm strong Oscillator

13Three point tracking is

achieved with?

Padder capacitor Double spolting

14

For super conductor the

valve of relative

premeability is?

Zero Unity

15A ferrite is?

A non-conductor with

magnetic properties

A microwave

semiconductor

16A pin diode is?

A microwave mixer

diode

Prefferred as a

microwave switch

17

The behaviour of which of

the following device is

governed by bulk effect?

PIN code Gunn diode

18 VOR stands for?

VFL omni range VHF omni range

19

Which class of amplifier

has the lowest efficiency?

Class A Class AB

20Input & output signals for

CE amplifier are always?

Equal In phase

21 A triac is like a?

Unidirectional SCR Bidirectional SCR

22Gang is a?

Fixed capacitor

Variable capacitor with

oil as dielectric

23

When compared with CB

amplifier, a CE amplifier

has?

Lower current

amplification

Higher current

amplification

24A wave guide can be

considered as?

Band pass filter High pass filter

25

A matched load in

communication is one in

which?

Reflection is zero Reflection is unity

26

Antenna used for T.V.

reception is?

Marconi Antenna Horn Antenna

27

By maximum power

transfer theorem, if the

load is inductive, the

source should be?

Inductive only Capacitive


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28

The voltage across a

capacitor _________the

current through it

by___________?

lag, 45 deg. lag, 90 deg.

29A frequency of 900 Hz is

called?

Audio frequency Radio frequency

30

The total voltage in a

series RL

circuit_________the

current by an angle

of________?

lags, 90 degreelags between 0 and 90

degree

31Time constant of a series

R-L circuit is given by?

LR L/R

32A capacitor stores energy

in?

Dielectric dipole A magnetic field

33Function 2S

has? (S+1) (s+7) One zero and two poles No zero and one pole

34In a series RLC circuit, at

the resonant frequency?

Current is minimumVoltage across "C" is

minimum

35

To increase the Q-factor

of an inductor it is wound

with?

Thinner wire Thicker wire

36An oscillator circuit is

mainly?

DC to AC converter DC to DC converter

37

For good stability, the

tuned circuit should

have?

High Q Low R

38In a series RLC circuit, at

the resonant frequency?

A =0 A =1

39A phase shift oscillator is

consists of?

RC circuits RL circuits

40

The Barkhausen criterion

gives?

Condition for gain in

transistorsMaximum gain condition

41Inverter is an equipment

for tranforming?

AC to DC DC to AC

42Super transistor is a?

Cascade configuration CE configuration


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43

When both the junction of

transistor are forward

biased, it is said to be in

the?

Active Region Passive Region

44

An oscillator using a

capacitive voltage divider

to provide feedback is?

Hertley Colpitts

45

Which one of the

following types of

Indicating instruments is

an electrometer?

Electrodynamometer PMMC

46

Wein bridge is used for

measurement of

frequency in the applied

voltage waveform is?

Sinusoidal Square

47Highest efficiency is

achieved in Amplifier of?

Class A Class B

48

Which one of the

following is suitable for

low power oscillator only?

Tunnel Diode Gunn Diode

49

in a coaxial cable,

braided copper is used as

a?

Conductor Shield

50 Which of the following isan active transducer?

Photoelectric Photovoltaic

51The input impedence of

CRO is nearly?

Zero Infinity

52 A high "Q" coil has?

Large bandewidth High losses

53A "RADOME" is a?

Radar housed in done A Type of Radar

54Full Adder circuit can be

implemented by?

Multiplexer Half adder

55

The difference between

sequential andcombinational circuit is

that?

Combinational circuit

store bits

Combinational circuit

have memory

56

Effect of adding poles

and zeros can be

determined quickly by?

Nicholas chart Nyquist plot


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57PCM has biggest

advanta e over AM is?Larger bandwidth Serration

58A Darligton pair is used

for?

Low distortion High frequency range

59

An ideal op-amp has?

Infinite input and output

impedence

Very low input and

output impedence

60In ideal power supply

has?

Zero internal resistanceVery large input

resistance

61

Number of switching

functions of 3 variables

is?8 16

62

If a memory chip is of

size 256x1 bits, then the

number of chips required

to make up 1024 bytes ofmemory is?

24 32

63

Which one of the

following is an universal

gate?OR NOT

64Line of sight transmission

is?

Used in radio frequency

below 1MHzUsed in VHF only

65Which of the following is

error correcting code?

EB CDIC GRAY

66Which of the followingmaterial is not a

semiconductor

Silica Selenium

67

Which of the following

vacuum tubes can not be

used as an amplifier

Diode Triode

68Tank circuit mainly

comprises ofResistance and

CapacitorResistance and inductor

69 Magnetron is a High power amplifier Low power amplifier

70For a good conductor the

skin depth varies Directly as frequency Directly as square root offrequency.

71

The Characteristic

Impedance of losses in

transmission line is given

by

Z= LC Z= C/L


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72Which of the following is

an Timer ICIC 741 8086

73Third harmonics of 150

Hz is100 Hz 450Hz

74

Pure metals generally

have?Negaive temperature

coefficient

Positive temperature

coefficient

75Semiconductors generally

havePositive temperature

coefficient

Negative temperature

coefficient

76 IC 741 is an? Timmer IC Op-amp IC

77

In comparision to

Amplitude modulation

Frequency modulation

offers?

Higher noiseHigher difficulty in

tunning

78

IC of which of the

following logic familyoffers advantage of

lowest power

consumption?

C MOS TTL

79

Stray capacitance comes

into picture of electronics

circuit when it is used in?Low frequency High Frequency

80

Which of the following is

true for negative

feedback for anamplifier?

Offers lower gain than

amplifier of with out

negative feedback

Offers higher gain than


negative feedback

81

Resultant resistance

obtained from paralleling

of two unequal resistors

is?

Lower than higher

resistance value but

higher than lower

resistance value

Higher than both

resistance value

82

NAND gate can be made

by combination of? OR and Not gate AND and Not gate

83

Two resistance of equal

value "R" are connectedin parallel then the

resultant resistance will

be?

R 2R


7/17

84

Two capacitor of equal

value "R" are connected

in parallel then the

resultant capacitance will

be?

C/2 C

85

Two inductors L1 & L2connected in series then

the resultant value will

be?

L1+L2

L1xL2L1+L2

86In binary system 11 is

written as? 1000 1011

87The parity bit is added for

purpose of?Indexing Coding

88RAM is acronym of?

Read around memory Real Access memory

89Piezoelectric crystals

are?Passive transducer Random transducer

90

Filter which passes

signals of frequencies

between two fixed

frequencies is called?

Band Pass Filter All pass filter

91

Silicon diode is less

suited for low voltage

rectifier operation

because?

It can withstand low

temperatureIt is less reliable

92

A measure of

reproducibility of

measurements is known

as?

Accurcay Fidelity

93

For very high resistance

measurement the

instrument used is?

Multimeter Potentiometer

94

A capacitor of 10

microfarad charged upto

10 volts will have charge

stored equal to?

10 micro coulombs 100 micro coulombs

95

With charge of 15

coulombs current that

could be flown is equal

to?

5 Ampers for 05

seconds5 Ampers for 03 minutes


8/17

96

Internal Resistance of the

ammeter should ideally

be?

Zero Very large

97

Internal Resistance of

voltmeter should ideally

be?

Very large Very small

98DVM is abbreviation for?

Digital Vaccum meter Digital Volume meter

99

The Lissajous pattern

obtained on a CRO is

used to determine?

Phase shift and

FrequencyCurrent

100The loss angle in the

capacitor should be?As high as possible Infinity


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Option 3 Option 4 Correct

Answer Difficulty Level

(5) (6)(7) (8)

Mobile Sets Wireless receiver sets b 2

Very low input resistance Depends on use a 3

Minimum distortion isdesired Complex voltage gainrequired c 2


Class AB

Eliminating grounding

voltagec 3

PNP MOSFET d 1

Input resistance =

Infinity, Outputresistance=0

Input resistance =Infinity,

Outputresistance=Infinity

c 2

Power RatioNot defined in terms of

Ratioc 3

Oscillators All of these d 1

High gain bandwidth

product

Its current controlled

behavioura 3

Zero feedback No feedback b 1

May increase or

decreaseRemains constant c 1

Name of the Discipline for

Question BankELECTRONICS


10/17

Hartley oscillator Colpitts oscillator c 2

Variable selectivity Double conversion a 3

Infinite Negative a 2

An insulator An metallic compound a 3

A metal semi-conductor A microwave detector b 1

Tunnel diode IMPATT diode b 2

Visual omni range Vedio omni range b 2

Class B Class C a 3

Out of phase Can not determined c 4

NPN transistor MOSFET b 3

Variable capacitor with

air dielectric

Electrolytic capacitor c 2

Low input resistance High input resistance b 3

Low pass filter Band stop filter b 2

Partial reflection Partial transmission a 1

Helical Antenna Yagi Antenna d 1

Resistive Inductive & Resistive b 3


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leads, 0 leads, 90 b 2

High frequency Ultra high frequency a 2

leads, between 0 degree

& 90 degree

leads, between 90

degree & 220 degreec 3

L2R LR2 b 2

An electrom agnetic field A gravitational field a 3

No zero and two poles One zero and no pole a 3

lmpedence is maximum Current is maximum d 1

Longer wire Coiled coil wire b 2

AC to DC converter AC to AC converter a 2

Low L Low C a 2

1+A =0 A=1/ c 2

LC circuits RLC circuits a 3

The phase shift required

for oscillation

Maximum power

theoremc 3

AC to AC DC to DC b 2

Darlington configuration Matched pair c 1


12/17

Cut-off Region Saturation Region d 1

Armstrong Monostable b 1

Electrostatic Moving iron c 2

Rectangular Triangular a 3

Class AB Class C d 3

IMPATT Diode LSA a 2

Dielectric Jacket b 2

Photo conductive Photoemission d 2

100 Ohms One megaohms d 2

Low losses Flat response c 2

Protective cover for

antennaDish antenna c 2

AND or OR gate Decoders a 3

Sequential circuit store

bits

Sequential circuits have

memoryd 1

Bode plot root locus c 3


13/17

Larger Noise Squelching a 2

High power gain High current gain d 2

Low input resistance and

low gain

Infinite input impedence

and zero outputimpedence

d 1

Very small input

resistanceUsed in VHF and UHF a 2

64 128 a 3

12 8 b 3

AND NAND d 3

Used in sound signal

onlyUsed in VHF and UHF d 1

Hamming ASCII c 2

Gallium arsenide Germanium. a 2

Tetrode Pentode. a 3

Inductor and Capacitor Inductor only c 3

High power oscillator Inductor only c 2

Inversely as frequency. Inversely as square rootof frequency d 2

Z= L/C Z= LC c 2


14/17

555 BC 107 c 3

300 Hz 50 Hz b 3

Neutral temperature

coefficient

Zero temperature

coefficient b 2

Zero temperature

coefficient

Neutral temperature

coefficientb 2

Power supply IC Dosen't exists b 2

Higher bandwidth Lower bendwidth c 1

ECL RTL a 1

DC Supply Very low frequency b 1

Offers equal gain as


negative feedback

Offers fluctuating gain as

compaired to amplifier of

without negative

feedback

a 1

Lower than lower

resistance value

Almost equal to higher

resistance valuec 2

OR and OR gate Not and not gate b 2

R/2 R/4 c 2


15/17

2C C/4 c 3

L1+L2

2 2L1 x L2 a 3

B1 1001 b 3

Controlling Error-detection d 3

Read all memoryRandom Access

Memoryd 3

Secondary transducer Active transducer d 3

Band stop filter High pass filter a 2

It is high voltage diode Its cut-in voltage is high d 1

Precision Resolution c 2

Wheatstone bridge Megger d 1

01 micro coloumbs 100 coulombs b 2

5 Ampers for 01 second3 Ampers for 05

secondsd 3


16/17

Very very large 1000 Ohms a 3

Zero 100 Ohms a 1

Digital voltage

measurementDigital voltmeter d 2

Distortaion Voltage a 1

Zero Exactly 90 Degree c 2


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