UPSC IES 2019 (Prelims) Question Paper for Electronics and Telecommunication Engineering

evineatg Service (I)) Examy2019
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T.B.C. : VBY—S—ELX Test Booklet Series

Serial No.

TEST BOOKLET
004 GO 85

ELECTRONICS AND TELECOMMUNICATION
ENGINEERING
Time Allowed : Three Hours Maximum Marks: 300

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DO NOT OPEN THIS TEST BOOKLET UNTIL YOU ARE TOLD TO DO SO

1. Consider a common-emitter current gain 5. In the Wien bridge oscillator, the 00
of p = 150 and a base current of phase-shift is met by using lead-lag
in = 15 µA. If the transistor is biased in network and by using
the forward active mode, the collector
and emitter current will be (a) inverting op-amp

2.25 mA and 2.27 mA non-inverting op-amp

3.25 mA and 2.27 mA feedback op-amp

2.25 mA and 1•37 mA high-gain op-amp
3.25 mA and 1•37 mA
6. What is the frequency of oscillation for an
2. The input to a bridge rectifier is 230 V RC phase-shift oscillator with R of 10 Icfl
(r.m.s.), 50 Hz. The d.c. output voltage and C of 0.001 µF in each of its three
and the ripple factor with RL of 100 SI RC sections?
and capacitor filter of 100012F are
5.0 kHz
207 V and 0.028
5.5 kHz
325 V and 0 • 028
6 • 0 kHz
207 V and 0.020
(d) 5.5 kHz
325 V and 0.020

7. When there is no clock signal applied to
3. The effect of reduction in effective base
CMOS logic circuits, they are referred
width due to increase in reverse voltage
to as
of BJT is
Hall effect complex CMOS logic circuits

Early effect static CMOS logic circuits

Zener effect NMOS transmission gates
Miller effect random PMOS logic circuits

4. What is the drain current for a 8. One form of NMOS circuit logic that
D-MOSFET having the characteristic minimizes power dissipation and
values IDss of 10 mA, Vasmo of —4 V maximizes device density is called
and IlDs of + 2 V?
pass transistor logic
22.5 mA
17•5 mA sequential logic circuit

12•5 mA NMOS SRAM cell

2•5 mA NMOS transmission gate

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9. The ideal op-amp has 12. The light intensity 3 m from a lamp that
emits 25 W of light energy will be
infinite voltage gain and zero input
impedance 243 mW/m 2

infinite voltage gain and infinite 232 mW/m 2
bandwidth
221 mW/m 2
zero voltage gain and infinite CMRR
210 mW/m 2
zero output impedance and zero
CMRR
13. Two resistances, one of 30 Q and another
of unknown value, are connected in
parallel. The total power dissipated
10. A d.c. voltage supply provides 60 V
in the circuit is 450 W when the
when the output is unloaded. When
applied voltage is 90 V. The unknown
connected to a load, the output drops
resistance is
to 56 V. The value of the voltage
regulation is
45.Q

3.7% 35Q

5.7% 30Q

7.1% 20Q

9.1%
14. An electric kettle contains 1. 5 kg of water
1
at 15 °C. It takes 15 minutes to raise
the temperature of water to 95 °C. If the
11. In optical communication, the maximum
heat loss due to radiations and heating
angle in which external light rays may
the kettle is 15 kcalories and the
strike the air/glass interface and still
supply voltage is 100 V, the current
propagate down the fiber is called as
taken will be

critical angle 8. 0 A

numerical aperture 7•1A

angle of refraction 6. 3 A

acceptance angle 5 -4 A

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15. A heater element is made of nichrome 18. An inductor of 0•S H inductance and
wire having resistivity equal to 90 Q resistance is connected in parallel
100 x 10-8 Q m and diameter of with a 20 AF capacitor. A voltage of
0.4 ram. The length of the wire 230 V at 50 Hz is maintained across the
required to get a resistance of 40 Q circuit. The total power taken from the
will be nearly source is nearly

9m 588 W

145W
7m
135 W
5m
125 W
3m

19. A 240 V shunt motor with the armature
16. A car is travelling at 72 km/h. If the resistance of 0.1 Q runs at 850 r.p.m.
length of an axle is 2 m and the vertical for an armature current of 70 A. If its
component of the earth's magnetic field speed is to be reduced to 650 r.p.m., the
is 40 ab/m2 , the e.m.f. generated in resistance to be placed in series for an
the axle of the car is armature current of 50 A is nearly

2 6 mV 082Q

2.2 mV 1 14 Q

1- 6 mV 124Q

1.2 mV 1. 34 Q

17. In a telephone receiver, the size of each of 20. A 200 V d.c. shunt motor with armature
the two poles is 1.2 cm x 0.2 cm and resistance of 0.2 £1 and carrying a
the flux between each pole and the current of 50 A is running at 960 r.p.m.
diaphragm is 3 x 10-8 Wb. The force If the flux is reduced by 10% at constant
torque and with negligible iron and
attracted to the poles will be nearly
friction losses, the speed will be nearly
0.15 N 1280 r.p.m.

0.20 N 1170 r.p.m.

0. 30 N 1100 r.p.m.

0.40 N 1060 r.p.m.

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21. Which of the following statements are 23. Which of the following statements are
correct for d.c. shunt motor? correct for a fully charged lead-acid cell?

Speed of a shunt motor is Gassing occurs at both electrodes.
sufficiently constant.
The terminal voltage is 2 6 V.
For the same current input, its The specific gravity of the
starting torque is not as high as electrolyte is 1.21.
that of a series motor.

The motor can be directly coupled Select the correct answer using the code
to a load such as a fan whose given below.
torque increases with speed.
1 and 2 only
Select the correct answer using the code 1 and 3 only
given below.
2 and 3 only
2 and 3 only
1, 2 and 3
1 and 3 only

1 and 2 only 24. Which of the following statements are
correct for synchronous motors?
1, 2 and 3 Synchronous motors are well-
suited for direct connection to
reciprocating compressors.
22. Consider the following materials :
Over-excited synchronous motors
Lead peroxide are most commonly used for power
factor improvement.
Sponge lead
Synchronous motors are generally
Dilute sulphuric acid used for current regulation of long
transmission lines.
Which of the above are active materials
of a lead-acid battery? Select the correct answer using the code
given below.
1 and 2 only
1, 2 and 3
1 and 3 only
1 and 3 only

2 and 3 only 1 and 2 only

1, 2 and 3 2 and 3 only

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25. Which crystal system requires six lattice 28. Consider the following data for copper :
parameters to fully specify its unit cell?
Energy for vacancy formation
Triclinic is 0.9 eV/atom

Atomic weight is 63.5 g/mol
Monoclinic
Density is 8•4 g/cma at 1000 °C
Cubic
The equilibrium number of vacancies
Hexagonal per cubic meter at 1000 °C will be

3.2x102°
26. The minimum cation-to-anion radius
ratio for the coordination number 3 is 3 .2 x 1025

0.175 2 .2 x 1020

2 .2 x 1025
0.155

0.135 29. Which of the following are electrical
insulating materials?
0.115 Lucite
Mica
27. Which of the following materials are Bakelite
categories of ceramic materials?
Select the correct answer using the code
Oxides—Alumina, Zirconia given below.
Non-oxides—Carbides, Borides, 1 and 2 only
Nitrides and Silicides
1 and 3 only
Composites—Particulate reinforced
combinations of oxides and 2 and 3 only
non-oxides
1, 2 and 3
Select the correct answer using the code
given below. 30. The magnitude of the energy gap for an
insulator is
1 and 2 only
less than 1 eV
1 and 3 only
between 2 eV to 3 eV
2 and 3 only more than 3 eV

1, 2 and 3 between 1 eV to 2 eV

VBY—S—ELX/51A 6

31. In a 440 V, 50 Hz transformer, the total 34. Which one of the following materials
iron loss is 3700 W. When the applied is having the highest electrical
voltage is 220 V at 25 Hz, the total iron conductivity at room temperature?
loss is 750 W. The eddy current loss at
Silver
the normal voltage and frequency will be
Copper
(a) 1000 W Gold
1200 W Platinum

1400 W 35. Consider the following processes :
1850 W Sol-gel process
Electrodeposition
Plasma-enhanced vapour
32. A transformer core is wound with a coil
decomposition
carrying an alternating current at a
frequency of 50 Hz. The hysteresis loop Gas-phase condensation
has an area of 60000 units, when the Sputtering technique
axes are drawn in units of 10-4 Wb m-2 The above processes are related to
and 102 A m-1. If the magnetization
is uniform throughout the core volume analysis of nano-powders
of 0.01 m3, then the hysteresis loss sintering of nano-powders
will be synthesis of nano-powders

200 W microwave sintering of nano-
powders
230 W
36. In the superconducting state, the flux
270 W lines of a magnetic field are ejected out
of the superconductor as per
300W
Curie effect

33. The process of evaporating a metal in an Faraday's effect
inert atmosphere and allowing it to Maxwell's effect
condense on the surface of a cold finger,
Meissner effect
which is kept at liquid nitrogen tempe-
rature of 77 K, is known as 37. A null type of instrument as compared to
d.c. arc method a deflection type of instrument
has a higher accuracy
gas-phase condensation
is less sensitive
sonohydrolysis is more rugged
flame pyrolysis is faster in response

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38. A Wheatstone bridge requires a change of A resistance is determined by voltmeter-
7 52 in the unknown resistance arm of ammeter method. The voltmeter reads
the bridge to produce a change in 100 V with a probable error of ±12V
deflection of 3 mm of the galvanometer. and the ammeter reads 10 A with a
The sensitivity and the deflection factor probable error of ± 2 A. The probable
will be nearly error in the computed value of the
resistance will be nearly
0.23 mm/52 and 2•3 52/mm
0•5 52
0.43 mm/52 and 2•3 52/mm
1. 3 Q
0.23 mm/52 and 1•3 52/mm
2•3 52
0.43 mm/Q and 1.3 Q/mm
3•6 Q
39. The galvanometer used in a Wheatstone
bridge as a detector can detect a current A temperature-sensing device can be
as low as 0.1 nA and its resistance modeled as a first-order system with
is negligible compared to internal a time constant of 6 s. It is suddenly
resistance of the bridge. Each arm of subjected to a step input of
the bridge has a resistance of 1 k.Q. 25 °C-150 °C. The indicated tempe-
The input voltage applied to the bridge rature in 10 s after the process has
is 20 V. The smallest change in the started will be
resistance that can be detected is
118.2 °C
10 µ52
126.4 °C
20 ptgl
134 • 6 °C
301152
142 8 °C
40 452
43. In a parallel circuit having two branches,
40. The inductance of a 25 A electrodynamic the current in one branch is
ammeter changes uniformly at the 4 = 10 ± 2 A and in the other is
rate of 0 003511H/degree. The spring 1.2 -= 200 ± 5 A. Considering errors in
constant is 10-6 N m/degree. The angle both /3. and 12 as limiting errors, the
of deflection at full scale will be total current will be

(a) 135° 300 ± 5 A

04 125° 300 ± 6 A

115° 300 ± 7 A

105° 300 ± 8 A

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44. A 0-150 V voltmeter has a guaranteed 47. The applications of photomultipliers are
accuracy of 1% of full-scale reading. The seen in
voltage measured by this instrument is
75 V. The limiting error will be night vision equipment, medical
equipment
5% mechanical counters, timers

4% translational, optical instruments

3% ultrasonic transducer, infrared
imaging
2%
48. A capacitance of 250 pF produces
resonance with a coil at a frequency of
45. A quartz piezoelectric crystal having a
106 Hz, while at the second
thickness of 2 mm and voltage
sensitivity of 0.055 V m/N is subjected harmonic of this frequency, resonance
to a pressure of 1. 5 MN/m2 . The voltage is produced by a capacitance of 50 pF.
output will be The self-capacitance of the coil will be
nearly
165 V
16.7 pF
174V
20.5 pF
183 V 24.3 pF

192 V 28.1 pF

49. Consider the following data for twigs and
46. A resistance wire strain gauge with a links :
gauge factor of 2 is bonded to a steel
structural member subjected to a stress N = Number of nodes
of 100 MN/m2 . The modulus of L = Total number of links
elasticity of steel is 200 GN/m2 . The
B = Total number of branches
change in the value of gauge resistance
due to the applied stress will be The total number of links associated
with a tree is
0•05%
B- N +1
0.10%
B- N -1
030% B+ N+ 1

0•60% 2B- N+1

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50. In ABCD parameters, A and Care called 53. Consider the following RC circuit. The
capacitor has an initial charge qo such
(a) reverse current ratio and transfer that it opposes the flow of charging
admittance current :

reverse voltage rato and transfer
impedance

reverse current ra do and transfer
impedance

(d) reverse voltage rado and transfer The response of the circuit i(t) will be
admittance
(a) E - 1±c
ffil) e
( R PC)

51. A coil having resistance of 10 Q and 170e-
-—
inductance of 1 H is switched on to a RC
direct voltage of 100 V. The steady-state
E
value of the current will be —e RC

10 A go
(d) (— + — e RC
R RC)
15 A
54. In the following circuit, switch K is
20A thrown from position A to position B at
time t = 0, the current having previously
25 A reached its steady state :
A

52. A coil has R = 10 Q and L = 15 FL The
voltage at the instant when the current 5v
is 10 A and increasing at the rate of 2H
5 A/s will be

(a) 125 V The current i(t) after switching will be
(a) 5e-5t
(b) 150 V
4e-St
175 V
(c) 3e-52
(d) 200 V (d) e-St

VBY-S-ELX/51A 10

55. What is the condition for reciprocity 58. A supply of 250 V, 50 Hz is applied to a
and symmetry in Y-parameter series RC circuit. If the power absorbed
representation? by the resistor be 400 W at 160 V, the
value of the capacitor C will be nearly
(a) Y21 =Y11 and Y22 =X'21
(a) 30- 5 [IF
(b) Y21 = Y12 and Y11= Y22
41.5 pF
1721 = Y22 and Yu Y22
(c) 64 -0 1.1F
(d) 1711 Y22 and Y21 = '1'22
(d) 76.8 IS

56. In hybrid parameters, hu and h21 are
called as 59. A 50 Hz sinusoidal voltage V= 311sin cot
is applied to an RL series circuit. If the
input impedance and forward magnitude of resistance is 5 Q and that
current gain of the inductance is 0.02 H, the r.m.s.
value of the steady-state current and
reverse voltage gain and output the relative phase angle are nearly
admittance
19.6 A and 51.5°
input impedance and reverse
voltage gain 27.4 A and - 51- 5°

output impedance and forward 19.6 A and -51.5°
current gain
27.4 A and 51-5°

57. Consider the following equations :
60. In a series RC circuit, the values of
= 6V2 -4/2 R = 10 51 and C=25 nF. A sinusoidal
voltage of 50 MHz is applied and
= 7V2 -212 the maximum voltage across the
capacitance is 2.5 V. The maximum
voltage across the series combination
A, B, C and D parameters are will be nearly

(a) 6, -4 Q, 7 mho and -2 (a) 172.7V

(b) 6, 4 Q, 7 mho and 2 184•5V

-6, 4 0, -7 mho and 2 (c) 196.3 V

(d) 6, 4 Q, -7 mho and -2 (d) 208•1V

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61. The peak-to-peak ripple voltage for a 64. Three amplifiers of gain
half-wave rectifier and filter circuit
operating at 60 Hz, which has a 680 jsF A = (NZ
2
- 60°
reservoir capacitor, an average output of
28 V and 200 Q load resistance, will be
are connected in tandem. The feedback
nearly
loop is closed through a positive gain
of 0.008 .
(a) 2. 5 V
A A A
(13) 3•4 V

4 .3 V 0 008

5•2V The magnitude of Ao for the system to
be oscillatory will be

(a) 0.2
62. The components of full-wave voltage
doubler circuit are (b) 0.1

(c) 5, 0
(a) 2 diodes and 1 capacitor
(d) 10.0

(b) 4 diodes and 1 capacitor
65. The output voltage from a 5-bit ladder
type DAC that has a digital input of
(c) 2 diodes and 2 capacitors 11010, and by assuming 0 = 0 V and
1 = + 10 V, is nearly
(d) 4 diodes and 2 capacitors
(a) 26. 0 V

(b) 16 3 V
63. An amplifier has a signal input voltage Vi (c) 103V
of 0.25 V and draws 1 mA from the
source. If the amplifier delivers 8 V to a (d) 8•1V
load of 10 mA, the power gain is
66. An 8-bit D/A converter has step size of
20 mV. The full-scale output and the
(a) 340
resolution will be nearly

(b) 320 51V and 0.3%

4 • 6 V and 0-4%
250
(c) 5.1 V and 0-4%

(d) 150 (d) 46 V and 0,3%

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67. For 555 astable multivibrator, if 70. Which one of the following types of
C = 0. 01 µF, RA = lOkQ, RB = 50 lcO, instructions will be used to copy from
the frequency and the duty cycle will be the source to the destination location?
nearly
(a) Arithmetic instructions
(a) 1.6 kHz and 54.5%
(b) Data transfer instructions
1. 3 kHz and 54 5% (c) Logical instructions
1• 6 kHz and 46.5% (d) Machine control instructions
1.3 kHz and 46.5c/c.
71. A cascaded arrangement of flip-flops,
where the output of one flip-flop drives
68. Consider the following expression : the clock input of the following flip-flop,
A•B•C•D+A•B•• +A•B•C•15 is known as
synchronous counter
+A- • D+ A• B.C. D• E
4 ripple counter
+A•13.-
e•D•E+A•B•Ei•DsE
ring counter
The simplification of this by using
theorems of Boolean algebra will be up counter

A+B 72. The number of flip-flops required to
construct an 8-bit shift register will be
A ED B
32
(A + B)(A • B)
16
A•B
8
69. An electric power generating station 4
supplies power to three loads A, B and
C. Only a single generator is required 73. Which one of the following specifications
when any one load is switched on. When does not fit for a single-mode fiber?
more than one load is on, an aineiliary
generator must be started. The Boolean The bandwidth is 1 GHz/km.
equation for the control of switching of
The digital communication rate is
the auxiliary generator will be
excess of 2000 Mbytes/s.
AA + BB + CC
More than 100000 voice channels
ABC + BCA + CAB are available.

AB + AC
The mode field diameter (MFD;
spot size) is larger than the core
AB + AC + BC diameter.

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74. For a binary FSK signal with a mark 77. An AM wave with modulation index 0.8
frequency of 49 kHz, a space frequency has total sideband power of 4.85 kW.
of 51 kHz and an input bit rate of The carrier power and the total power
2 kbps, the peak frequency deviation radiated will be nearly
will be
12-2 kW and 20 kW
0-5 kHz
1.0 kHz 15.2 kW and 20 kW
2.0 kHz
12.2 kW and 25 kW
4•0 kHz
15.2 kW and 25 kW
75. A random process X(t) is defined as
X(t) = 2 cos (2nt + Y)
78. A 360 W carrier is simultaneously
where Y is a discrete random variable
modulated by two audio waves with
1
with P (Y = 0) =2- and P i. modulation percentages of 55 and 65
=
fr =
respectively. The effective modulation
The mean p(1) is index and the total power radiated are
1
(a)
4 0.85 and 490.5W
1
3 0•65 and 490. 5 W

1
0.85 and 4505W
2
0-65 and 4505W

76. A source produces three symbols A, B
1 79. An amplitude modulated amplifier has a
and C with probabilities P(A) = -
2' radio frequency output of 50 W at 100%
1 modulation. The internal loss in the
and P(C) = . The source
4 4 modulator is 10 W. The unmodulated
entropy is carrier power is

1bit/symbol 40 W
2
1 bit/symbol
50W
1-
1 bits/symbol
4 60 W
1
1- bits/symbol
2 80W

VBY-S-ELX/51A 14

80. For an FM receiver with an input 83. In a PCM system, non-uniform
signal-to-noise ratio of 29 dB, a noise quantization leads to
figure of 4 dB and an FM improvement
factor of 16 dB, the pre-detection and (a) increased quantizer noise
post-detection signal-to-noise ratios are (b) simplification of the quantization
process
25 dB and 41 dB
(c) higher average SNR
30 dB and 49 dB (d) increased bandwidth

25 dB and 49 dB 84. The bandwidth required in DPCM is less
than that of PCM because
30 dB and 41 dB
(a) the number of bits per code is
reduced resulting in a reduced bit
rate
81. For Gaussian and White channel noise,
• the capacity of a low-pass channel with the difference signal is larger in
a usable bandwidth of 3000 Hz and amplitude than actual signal
— =103 at the channel.output will be more quantization levels are
needed
15000 bits/s the successive samples of signal
often differ in amplitude
20000 bits/s
85. For the given transfer function
25000 bits/s Y(s) 1
qs)
Ms, s- + 3s + 2
30000 bits/s
the response y(t) for a step input
r(t) = Su(t) will be
82. For a PM modulator with a deviation
(a) _ 5e-t ]ti(t)
sensitivity K = 2.5 rad/V and a modu- 2 2
lating signal vm (t) = 2 cos (2n 2000t), the
peak phase deviation m will be

1.25 rad

2.5 rad

(t)
(e) 5.0 rad

(d) 7.5 rad where u(t) is a unit step input.

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86. The price for improvement in sensitivity 89. For a Type-2 system, the steady-state
by the use of feedback is paid in terms errors for unit step and unit ramp input
of are

loss of system gain
0 and co
rise of system gain
oc, and 0
improvement in transient response,
delayed response
0 and 0
poor transient response
co andoc
87. Consider a feedback system with the
characteristic equation
1 90. Consider the following statements
1+K -o regarding a parabolic function :
s(s + 1)(s+2)

The asymptotes of the three branches of A parabolic function is one degree
root locus plot of this system will form faster than the ramp function.
the following angles with the real axis
A unit parabolic function is defined
as
600, 120° and 3000

60°, 120° and 180° .1q, for t> 0
0 otherwise
60°, 180° and 300°

40°, 120° and 200°
Laplace transform of unit parabolic
1
function is
88. If the characteristic equation of a s3.
feedback control system is given by

s4 +20s3 +15s2 +2s + K = 0 Which of the above statements are
correct?
then the range of values of K for the
system to be stable will be 1 and 2 only

1<K<2.49
1 and 3 only
0 < K < 1. 49
2 and 3 only
1<K<4•49

0 < K < 3.49 1, 2 and 3

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91. Consider the following open-loop transfer 94. The frequency where magnitude M has a
function : peak value in frequency response is
known as
K(s+2)
G-
(s+ 1)(s + 4)
(a) normalized frequency

The characteristic equation of the unity
negative feedback will be (6) resonant frequency

(s+1)(s+4)+K(s+2)= 0 peak frequency

(s+2)(s+1)+K(s+4)= 0 tuned frequency

(s + 1)(s - 2) + K (s +4) = 0

(s + 2)(s + 4)+ K (s +1) = 0 95. For a lead compensator having transfer
function
92. The magnitude and phase relationship
between the sinusoidal input and the (s+
Gc (s) = zc) - +
steady-state output of a system is (s + Pc) (s+*)
called as

magnitude response
=
Pc
transient response
a= zc > 1
steady-state response Pc

frequency response

4. 'I < 0
93. A transfer function having all its poles
and zeros only in the left-half of the
s-plane is called Which of the above are correct?

a minimum-phase transfer
1 and 4
function

a complex transfer function 1 and 3

an all-pass transfer function
2 and 4
a maximum-phase transfer
function 2 and 3

VBY-S-ELX/51A 17 [ P.T.O.

The attenuation (magnitude) produced by 99. Add 8 and 9 in BCD code.
a lead compensator at the frequency of
maximum phase lead oi,„ = -Jai; is
00010111
b
(a) - (b)c
."-i- b
a
00010001

(c) VI) - a (d)
b
01110111

Consider the following statements :
A computer will have a multiply 10001001
instruction.
Multiply instruction will be imple-
mented by a special multiply unit.
100. Convert the binary number 11000110
Which of the following is correct? to Gray code.

(a) Both 1 and 2 are not architectural
design issues. (a) 00100101

(b) Both 1 and 2 are not organizational
issues. (Li) 10100100
(c) 1 is an architectural design issue
while 2 is an organizational issue. (c) 11100110
(d) 1 is an organizational issue while
2 is an architectural design issue. (d) 10100101

98. Consider a disk with an average seek
time of 4 ms, rotational delay of 2 ms,
rotation speed of 15000 r.p.m. and 101. The decimal value of the signed binary
512-byte sectors with 500 sectors per number 10101010 expressed in 2's
track. A file occupies all of the sectors complement will be
on 5 adjacent tracks. After reading the
first track, if remaining tracks can be
read with no seek lime, then the time -42
required in sequential organization to
transfer the file will be nearly
-86
0.01 second

0034 second -116
034 second

3.4 seconds -170

VBY-S-ELX/51A 18

102. Which of the following statements is/are 105. A soft error is a
correct?
(a) regular-nondestructive event
An address generated by the CPU is
commonly referred to as a physical (Li) random-nondestructive event
address.
random-destructive event
An address seen by the memory
unit is commonly referred to as a regular-destructive event
logical address.
The run-time mapping from virtual 106. A main memory can hold 3 page frames
to physical address is done by the and initially all of them are vacant.
memory management unit (MMU). Consider the following stream of page
Select the correct answer using the code requests :
given below.
2, 3, 2, 4, 6, 2, 5, 6, 1, 4, 6
1 only
If the stream uses FIFO replacement
2 only policy, the hit ratio h will be

3 only 11
(a) —
1, 2 and 3 3

103. In a cache with 64-byte cache lines, how
many bits are used to determine which
byte within a cache line an address
points to? (c)
11
16
2
8 (d)-
11
6
107. Which one of the following is an
3
advantage of assembly language over
high-level language?
104. A system has 64-bit virtual addresses
and 43-bit physical addresses. If the (a) Assembly language program runs
pages are 8 kB in size, the number of faster.
bits required for VPN and PPN will be
respectively (b) Writing of assembly language
programming is easy.
51 bits and 30 bits
Assembly language program is
30 bits and 51 bits
portable.
51 bits and 13 bits
Assembly language program
30 bits and 13 bits contains less instruction.

VBY-S-ELX/S1A 19 [ P.T.O.

108. Which of the following statements are 110. What is the value for the total charge
correct? enclosed in an incremental volume of
10-9 m3 located at the origin if
1. A pseudoidtruction is a machine
instruction.
D = e-x sin y a _e-x cos y ay + 2z a, C/M2 ?
A pseudoinstruction is an instruc-
tion to the assembler.
8 nC
The ORG (origin) is an example of
pseudoinstruction. 4 nC
It is not possible to use ORG more
2 nC
than once in a program.
1 nC
Select the correct answer using the code
given below.
111. The unit vector extending from origin
1 and 3 toward the point G(2, -2, -1) is

2 and 3
(a) 3 x 3y 3z
1 and 4

2 and 4

109. The vector RAB extends from A(1, 2, 3)
to B. If the length of RAB is 10 units
and its direction is given by

a= 0.6a, + 0- 64ay + 0.48az 3 x 3y 3

the coordinates of B will be

112. Ground waves progress along the surface
7az +4 8ay + 4 .8az of the earth and must be polarized

(a) horizontally
6a, + 6-1-ay +4 - 8a,
04 circularly
7az + + 7. 8az
elliptically

6a, + 8-4ay + 7. 8az vertically

VBY-S-ELX/51A 20

113. For a lossless line terminated in a short 116. For a standard rectangular waveguide
circuit, the stationary voltage minima having an aspect ratio of 2: 1, the
and maxima are separated by cutoff wavelength for T/vl i, 1 mode will
be nearly
(a) -A
8 (a) 0•9a

0•7a

05a

0.• 3a

117. The irises in the rectangular metallic
waveguide may be
inductive
resistive
114. The characteristic impedance of an
80 cm long lossless transmission capacitive
line having L = 0.25 li.H/m and
C= 100 pF/m will be Select the correct answer using the code
given below.
25g1
1, 2 and 3
40 52
1 and 2 only
50 52
1 and 3 only
80Q
2 and 3 only

115. It is required to match a 200 52 load to a
118. A 10 GHz signal is propagated in a
300 52 transmission line to reduce
waveguide whose wall separation is
the SWR along the line to 1. If it is
6 cm. The greatest number of half-
connected directly to the load, the
waves of electric intensity will be
characteristic impedance of the quarter-
possible to establish between the two
wave transformer used for this purpose
walls. The guide wavelength for this
will be
mode of propagation will be
275 LI
6.48 cm
260 52
4.54 cm
245 52
2•48 cm
230 52
1• 54 cm

VBY-S-ELX/51A 21 [ P.T.O.

119. In TEm, n mode, in and it are integers 121. Which of the following are the advantages
denoting the number of of Silicon over Insulator (SOW?
Lower diffusion capacitance
1 Smaller parasitic delay and lower
(a) - the wavelengths of intensity
2 dynamic power consumption
between each pair of walls
Lower threshold voltages

the wavelengths of intensity Select the correct answer using the code
3 given below.
between each pair of .walls
1, 2 and 3
1 1 and 2 only
4 the wavelengths of intensity
-
between each pair of walls 1 and 3 only
2 and 3 only
1
- the wavelengths of intensity
8 122. The finite state machine in which
between each pair of walls
the output is a function of the
current state and inputs
the output is a function of only the
120. Consider the following statements with current state
reference to dipole arrays :
Which of the following machines are
In broadside array, all the dipoles respectively correct for these styles?
are fed in the same phase from the
same source. Mealy machine and Moore machine

In end-fire array, the magnitude of Moore machine and Mealy machine
the current in each element is same State machine and Mealy machine
and there is no phase difference
between these currents. State machine and State machine

Which of the above statements is/are 123. In EPROMs, applying a high voltage to
the upper gate causes electrons to jump
correct?
through the thin oxide onto the floating
gate through the process known as
1 only
mask programming
2 only one-time programming
avalanche injection or Fowler-
Both 1 and 2
Nordheim tunneling

Neither I nor 2 erasing

VBY-S-EDC/51A 22

124. What is the range of values of a and b for 127. The frequency response and the main
which the linear time-invariant system lobe width for rectangular window are
with impulse response
. wN
sin
n 0 (a) 2 4n
and
n<0
2
is stable?
.0) N
sin
Both laic land lb] > 1 are satisfied (6) 2 It
and —
03
Both lc/ > land 'hi < 1 are satisfied 2
Both jai > 1 and Ibl> 1 are satisfied
sin-
Both at < land ILl < 1 are satisfied 2rc
and
. co N
sin
2
125. The special case of a finite-duration . oN
A sequence is given as sin -
4 81z
and
x(n)= (2, 4, 0, 31 2

The sequence x(n) into a sum of 128. A controller that takes control of the
weighted impulse sequences will be buses and transfers data directly
(a) 25 (n + 1) + 45 (n) + 38(n -2) between source and destination
bypassing the microprocessor is
25 (n) + 46 (n - 1) + 38 (n - 3) known as

28(n) + 48(n - 1) + 35(n - 2) DMA controller

23(n+ 1) + 45(n) + 36(n - 1) read-write controller

high-speed controller
126. The two advantages of FIR filters over
IIR filters are master-slave controller
they are guaranteed to be stable
129. A 2-byte instruction which accepts the
and non-linear
data from the input port specified in
they are marginally stable and the second byte and loads into the
linear accumulator is
they are guaranteed to be stable OUT <8-bit port address>
and may be constrained to have
linear phase IN <8-bit port address>

they are marginally stable and OUT R <8-bit port address>
non-linear IN R <8-bit port address>

VBY-S-ELX/51A 23 [ P.T.O.

130. Consider the following instruction : 133. Which one of the following is the correct
combination for a layer providing a
El
service by means of primitives in an
MV! A, 08H open systems interconnection?
SIM
Request, Indication, Response and
It means Confirm
disable all interrupts Request, Inform, Response and
enable all interrupts Service

disable RST 7.5 and 6.5 Request, Command, Response and
Action
enable RST 7.5 and 6-5
Request, Confirm, Indication and
131. The instruction BC 0x15 means Action

jump 15 bytes relative to the 134. A network uses a fully interconnected
program counter mesh topology to connect 10 nodes
copy and load 15 words in reverse together. The number of links required
direction to the program counter will be
move to a location by 15 bits to the 35
program counter 40
redirect (jump) to a location by 45
15 words relative to the program
counter 50

135. Which of the following are the advantages
132. Which of the following constraints are
to be considered by the designer while of packet switching?
designing an embedded system? Greater link efficiency than circuit
Selecting the microcontroller as a switching
controlling device Connections are not blocked when
traffic congestion occurs
Selecting the language to write the
software Direct channel established between
transmitter and receiver
Partitioning the tasks between
hardware and software to optimize No time is taken to establish
the cost connection

Select the correct answer using the code Select the correct answer using the code
given below. given below.
(a) 1,2 and 3 (a) 1 and 3
(b) 1 and 2 only (b) I and 2
(c) 1 and 3 only (c) 2 and 3
(d) 2 and 3 only (d) 3 and 4

VBY—S—ELX/51A 24

136. A message consisting of 2400 bits is to 138. Which of the following statements are
be passed over an internet. The message correct regarding CDMA?
is passed to the transport layer which
1. It is similar to GSM.
appends a 150-bit header, followed by
the network layer which uses a 120-bit 2. It allows each station to transmit
header. Network layer packets are over the entire frequency spectrum
transmitted via two networks, each of all the time.
which uses a 26-bit header. The
destination network only accepts up to 3. It assumes that multiple signals
add linearly.
900 bits long. The number of bits,
including headers delivered to the
destination network, is Select the correct answer using the code
given below.

(a) 2706 bits 1 and 2 only

1 and 3 only
(la) 2634 bits
(a) 2 and 3 only

2554 bits (d) 1, 2 and 3

2476 bits 139. Which of the following regarding cellular
systems with small cells are correct?
1. Higher capacity and robustness
137. In a communication network, 4 Ti 2. Needless transmission power and
streams are multiplexed to form 1 T2 have to deal with local interference
stream and 7 Ti streams are only
multiplexed to form 1 T3 stream.
3. Frequency planning and infrastruc-
Further 6 T3 streams are multiplexed
to form 1 T4 stream. If each Ti stream ture needed
is of 1- 544 Mbps, the data rate of 1 T4. 4. These require both circuit
stream should be switching and packet switching

Select the correct answer using the code
(a) 211. 8 Mbps
given below.

(b) 232.6 Mbps 1, 2 and 4

1, 3 and 4
243.4 Mbps
(c) 1, 2 and 3

(d) 274 .2 Mbps (d) 2, 3 and 4

VBY-S-ELX/51A 25 [ P.T.O.

140. A satellite is orbiting in the equatorial 143. The optical performance monitoring
plane with a period from perigee to involves
perigee of 12 h. If the eccentricity
=0O02, i = 0°, = 66063.17 km2 ,
(a) transport layer monitoring, optical
= 3.99 x 1014 m3 /82 and the earth's
signal monitoring and protocol
equatorial radius = 6378.14 km, the performance monitoring
semi-major axis will be

(a) 34232 km physical layer, network layer and
application layer monitoring
(13) 30424 km

26612 km data-link layer, presentation layer
and session layer monitoring
22804 km

transport layer, session layer and
141. A single-mode optical fiber has a beat application layer monitoring
length of 8 cm at 1300 nm. The value
of birefringence Bf will be nearly

1. 6 x 10-5

2 . 7 x 10-5
144. An earth station at sea level
communicates at an elevation angle of
3.2 x 10-5 35° with GEO satellite. The vertical
height of the stratiform rain is 3 km.
4•9 x 10-5 The physical path length L through the
rain will be nearly

142. Which one of the following instruments
is useful while measuring the optical (a) 6.3 km
power as a function of wavelength?

(a) Optical power attenuator (b) 5.2 km

Optical power meter
4.1 km
(c) Optical spectrum analyzer

(d) Optical return loss tester (d) 3.0 km

VBY-S-ELX/51A 26

Directions : Statement (I) :
The following six (6) items consist of two SRAM is used for cache memory and
statements, one labelled as 'Statement (I)' and DRAM is used for main memory.
the other as 'Statement (W. You are to examine
Statement (II) :
these two statements carefully and select the
answers to these items using the code given SRAM is somewhat faster than DRAM.
below :

Code: 148. Statement (I) :
In a multiuser system, each user is
Both Statement (I) and Statement assigned a section of usable memory
(II) are individually true and area and is not allowed to go out of the
Statement (II) is the correct assigned memory area.
explanation of Statement (I)
Statement (II) :
Both Statement (I) and Statement In multiuser system, there is a
(II) are individually true but software mechanism to prevent
Statement (II) is not the correct unauthorized access of memory by
explanation of Statement (I) different users.

Statement (I) is true but Statement
(II) is false Statement (I) :
The external surface of a crystal is an
Statement (I) is false but Statement imperfection in itself as the atomic
(H) is true bonds do not extend beyond the
surface.
Statement (I) : Statement (II) :
Sign-magnitude representation is The external surfaces have surface
rarely used in implementing the energies that are related to the number
integer portion of the ALU. of bonds broken at the surface.
Statement (II) :
There are two representations of zero Statement (I) :
in sign-magnitude representation. By organizing various 'optical
functions' into an 'array structure'
via nano-pattern replication, 'spatial
Statement (I) :
integration' is established.
Dynamic loading gives better memory-
space utilization. Statement (II) :
By adding a nano-optic layer or layers
Statement (II) :
to functional optical materials, the
In dynamic loading, an unused routine 'hybrid integration' is possible to be
is never loaded. achieved.

VBY-S-ELX/ 51A 27 [ P.T.O.

SPACE FOR ROUGH WORK

VBY-S-ELX/51A 28