MAHA SET 2019 Question Paper 2 Electronic Science

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A
ELECTRONIC SCIENCE
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(Name) ................................................ Seat No. ..............................................................
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JUN - 38219 (To be filled by the Candidate)
Time Allowed : 2 Hours] [Maximum Marks : 200
Number of Pages in this Booklet : 32 Number of Questions in this Booklet : 100
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2

Electronic Science
Paper II
Time Allowed : 120 Minutes] [Maximum Marks : 200
Note : This Paper contains Hundred (100) multiple choice questions. Each question
carrying Two (2) marks. Attempt All questions.

1. Which of the following compounds 3. Ebers-Moll model of BJT has two
is not suitable for Light Emitting coupled back to back diodes in
Diodes (LEDs) ? parallel with controlled current
sources.
(A) GaN
Which of the following is/are correct
(B) GaP
for switching applications ?
(C) SiCa
(1) If two diodes are both in
(D) GaAs
forward bias, then the BJT is
2. The distribution coefficient Kd is in a low impedance state.
given by
(2) If two diodes are both in reverse
CS
Kd bias, then BJT is in a high
CL
impedance state.
where C S = Concentration of
(3) If two diodes are both in
impurity in the solid
forward bias, then the BJT is
CL = Concentration in the liquid in high impedance state.
Which of the following is not a (4) If two diodes are both in reverse
function of Kd ? bias, then BJT is in low
(A) Growth rate impedance state.

(B) The impurity concentration (A) 1 and 2

(C) The temperature of the solid- (B) 2 and 4

liquid interface (C) 1, 2 and 3

(D) The orientation of the material (D) 2, 3 and 4

3 [P.T.O.

4. The technique of growing an 6. When the applied voltage across the

oriented single crystal layer on a PN junction is less than zero,

substrate wafer is called : then :

(A) Energy barrier between P and
(A) Oxidation

N junction becomes small
(B) Ion-implantation
(B) Drift current flow is favourable
(C) Epitaxy
(C) Diffusion current flow is
(D) Diffusion
favourable

5. Determine the values of current
(D) Drift current flow is not

amplification factor ( ) of two
favourable

different transistors having
7. Band gap of SiO2 in electron volt

1 = 0.99 and 2 = 0.98 :
is :

(A) 99 and 98 respectively
(A) 1.12 eV

(B) 49 and 99 respectively (B) 1.42 eV

(C) 99 and 49 respectively (C) 5 eV

(D) 98 and 99 respectively (D) 8 eV

4

8. The tunnel diode is useful in 10. Match List-I with List-II :

microwave oscillators and amplifiers List I

because of the following reasons : (a) Drift current

(b) Diffusion current
(A) Because it is lightly doped as

compared to PN junction diode. qVD
(c) ID IS e
kT
(B) Because it absorbs power.
(d) ID – IS
(C) Because it exhibits a negative
List II
resistance characteristic in the
(1) Ideal current when V D is
region between peak current IP negative
and valley current IV. (2) A current when there is an
electric field
(D) Because it exhibits a positive
(3) A current when there is
resistance characteristic in the
concentration difference for
region between peak current IP
either the electrons or holes or
and valley current IV. both

9. Identify which one of the following (4) Ideal current when V D is

materials cannot be used for the gate positive

electrode in a MOSFET ? Codes :

(a) (b) (c) (d)
(A) Aluminium
(A) (1) (2) (3) (4)
(B) Tungsten
(B) (2) (3) (4) (1)
(C) Gold
(C) (3) (4) (1) (2)

(D) Hafnium dioxide (D) (2) (3) (1) (4)
5 [P.T.O.

11. Find the short circuit current (IS.C.) 13. An ideal filter is the one which

of the following circuit using has :
Norton’s theorem :
(A) Zero attenuation in the pass

band

(B) Zero attenuation in the reject

band

(C) Infinite attenuation in the pass
(A) 4 A
band
(B) 2.5 A
(D) Finite attenuation in the reject
(C) 8 A
band
(D) 6 A
14. If a network contains B branches
12. A two port network is a rectangular
and N nodes, then the number of
box that represents a network
mesh current equations would be :
consisting of :
(A) B – (N – 1)
(A) Two pairs of ports

(B) N – (B – 1)
(B) Two pairs of terminals

(C) B – N – 1
(C) n-pairs of ports

(D) Two terminals (D) (B + N) – 1

6

15. A power factor of 1 indicates a : 18. What is the phase angle of a series

(A) Purely resistive element RLC circuit at resonance ?

(B) Purely resistive circuit (A) Zero

(C) Purely reactive element
(B) 90°
(D) Purely reactive circuit
(C) 45°
16. The Laplace transform of first
(D) 30°
derivative of function f(t) is :

(A) F(s)/s 19. A function is said to be even if :

(B) sF(s) – f(0) (A) f(t) = – f(– t)

(C) F(s) – f(0)
(B) f(t) = f(– t)
(D) f(0)
T
(C) f(t) = – f t – 0
17. State variable analysis is not 2

applicable to which of the following (D) f(t) = – f(t)
circuits ?
20. A superposition theorem is valid for
(A) A circuit consisting of resistors
which of the following ?
only

(B) A circuit with resistors and (A) Resistors with voltage sources

capacitors (B) Resistors with diodes
(C) A circuit with capacitors and
(C) Resistors with transistors
inductors
(D) Resistors with zener diodes
(D) A RLC circuit

7 [P.T.O.

21. Peak inverse voltage of diodes in
24. An amplifier having open loop gain
bridge rectifier is normally .............
times that of diodes in full wave of 100 is provided with a negative

rectifier with centre tap transformer. feedback having feedback factor of
(A) 3
0.02. The gain of the amplifier after
(B) 2
feedback will be :
(C) 0.5

(D) 1 (A) 50.00

22. Load regulation of a regulated power (B) 33.33
supply must be :
(C) 60.72
(A) As high as possible

(B) Varying with load impedance (D) 21.89

(C) As low as possible
25. The number of harmonics in addition
(D) Fixed to some intermediate
value to base frequency present in the

23. For a 3-stage amplifier having gains output of a tuned oscillator are :
of 5 dB, 10 dB and 15 dB respectively,
(A) 5
the overall gain would be :

(A) 750 dB (B) 2

(B) 15 dB
(C) 0
(C) 25 dB

(D) 30 dB (D) 1

8

28. Arrange the following semicon-
26. The output of the following circuit
ductor devices in increasing order of
will be : number of p-n junctions :
(i) diode
(ii) mosfet
(iii) bjt
(iv) scr
Codes :
(A) (ii), (i), (iii), (iv)
(B) (i), (ii), (iii), (iv)
(A) 2 V (C) (iii), (ii), (i), (iv)
(D) (iii), (ii), (iv), (i)
(B) 0 V
29. Match List-I with List-II :
(C) – 1 V List-I
(a) Active filters
(D) 1 V
(b) Multivibrators
27. Which of the following is not true (c) Schmitt trigger
in case of phase locked loop ? (d) Voltage regulator
List-II
(A) The phases of input and VCO
(i) Hysteris
are matched (ii) dc output

(B) The frequency of input and (iii) Pulse/Pulse train
(iv) R-C network with OP-Amp.
VCO are same
Codes :
(C) The VCO frequency tracks the (a) (b) (c) (d)
input (A) (i) (ii) (iii) (iv)
(B) (iv) (iii) (i) (ii)
(D) The VCO input is always zero
(C) (iv) (iii) (ii) (i)
when locked (D) (iii) (ii) (i) (iv)

9 [P.T.O.

31. The correct circuit of a Half Adder
30. Assertion (A) :

is :

An oscillator is basically
(A)
multivibrator with feedback.

Reason (R) :

R-C combination is used for low or (B)

high pass filtering.

(A) Both (A) and (R) are true and

(C)
(R) is correct explanation of (A)

(B) Both (A) and (R) are true and (R)

is not correct explanation of (A)
(D)

(C) (A) is true and (R) is false

(D) (A) is false and (R) is true

10

1
32. A 16-bit presetable counter with 1 34. An ADC used in 3 (Three and half)
2

MHz clock input can be used to digital multimeter is generally :

generate delay in the range of :
(A) 12 bit dual slope

(A) 0 to 64 mS with 1 S resolution
(B) 8-bit successive approximation

(B) 16 S with 1 S resolution
(C) 8-bit flash

(C) 6400 S with 1 mS resolution
(D) 8-bit dual slope
(D) 16 mS with 1 mS resolution
35. A state equation specifies :
33. Address and Data lines required to

(A) Next state as a function of
access 32 kB, byte organised memory

present state and inputs
will be :

(A) 12 and 8 (B) Clock applied

(B) 13 and 8 (C) Behaviour of a combinational

(C) 32 and 1 circuit

(D) 15 and 8 (D) Number of arithmetic operations

11 [P.T.O.

36. An 8-bit DAC is used to control a
38. What does the following HDL
linear valve with a 0 to 5 volt signal.

The valve is fully open if the signal statement mean ?

is 5 volts and closed if signal is 0

volt. An approximate resolution of wire [7 : 0] data-a;

the DAC in terms of volts and
(A) data-a is an 8-bit wire and the
percentage of valve opening will be :

(A) 0.02 V and 0.4% msb is bit 7

(B) 0.01 V and 10%
(B) data-a is a 4-bit wire and the
(C) 0.1 V and 10%

(D) 0.02 V and 4% msb is bit 7

37. Decimal to BCD priority encoder,
(C) data-a is a 4-bit wire and the
74147 will have :

(A) 8 inputs and 4 outputs lsb is bit 7

(B) 10 inputs and 8 outputs
(D) data-a is a 8-bit wire and the
(C) 10 inputs and 4 outputs

lsb is bit 7
(D) 8 inputs and 8 outputs

12

39. Match the List-I with List-II and 40. Assertion (A) :

select the correct answer using the
Universal shift register can be used
codes given below the lists :

List-I to implement accumulator.

(a) ALU
Reason (R) :
(b) Parity checker

(c) Shift register Addition and subtraction can be

(d) DRAM realised using shift registers.

List-II
(A) Both (A) and (R) are true and
(i) EXOR-Gate
(R) is the correct explanation
(ii) Full adder

(iii) MOS Transistor of (A).

(iv) DFF
(B) Both (A) and (R) are true but
Codes :
(R) is not the correct
(a) (b) (c) (d)

(A) (iii) (iv) (i) (ii) explanation of (A).

(B) (ii) (iii) (iv) (i)
(C) (A) is true but (R) is false.
(C) (ii) (iv) (iii) (i)

(D) (ii) (i) (iv) (iii) (D) (A) is false and (R) is true.

13 [P.T.O.

41. Microcontroller 8051 operates with 43. Which of the following special

function registers of 8051 is not bit
12 MHz oscillator and one machine
addressible ?
cycle is defined as 12 oscillator
(A) Accumulator (ACC)
periods. The execution time for a 4
(B) Program Status Word (PSW)
machine cycle instruction would
(C) Port O (PO)
therefore be :
(D) Serial Data Buffer (SBUF)
(A) 4 s
44. The fastest I/O data transfer uses :
(B) 8 s
(A) Polled I/O

(C) 1 s
(B) Interrupt driven I/O

(D) 2 s (C) Memory mapped I/O

42. 8086 works in multiprocessing mode (D) DMA

with the help of : 45. MUL A, B instruction of micro-

controller 8051 needs :
(A) Virtual memory
(A) 4 machine cycles
(B) DMA mode
(B) 2 machine cycles

(C) Max mode
(C) 1 machine cycle

(D) Minimum mode (D) 3 machine cycles

14

46. If the contents of code segment 48. The correct sequence of execution of

register of 8086 is 1000H and the Read/Write instruction in 8086 Min

instruction pointer is loaded with
mode of operation is :

0134H, then the instruction will be
(A) Set MN/MX high, Output high
fetched from :
on M/IO, Set ALE, Transfer

(A) 10000H
data

(B) 0134H
(B) Set MN/MX low, Output high

(C) 10134H
on M/IO, Transfer data, Set

(D) 1134H
ALE

47. Vector addresses of 8051 interrupts
(C) Output high on M/IO, Transfer

are located in :
data, Set ALE, Set MN/MX

(A) On-chip RAM high

(B) 0000-0023H (D) Transfer data, Set ALE, Set

(C) 0001-1000H MN/MX high, Output high

(D) External memory on M/IO

15 [P.T.O.

49. Match List-I with List-II : 50. ASSERTION (A) :

List I : Register
LCALL adder16 calls a subroutine
(a) IP
located at the indicated address.
(b) CX
REASON (R) :
(c) SI

The execution of LCALL results in
(d) SP

putting the 16-bit address on the
List II : Use

(i) Loop operations stack.

(ii) String manipulation (A) Both (A) and (R) are true and

(iii) Modular programming (R) is the correct explanation

(iv) Code access of (A)

Codes :
(B) Both (A) and (R) are true but
(a) (b) (c) (d)
(R) is not the correct
(A) (iv) (ii) (iii) (i)
explanation of (A)
(B) (ii) (i) (iii) (iv)
(C) (A) is true but (R) is false
(C) (iv) (i) (ii) (iii)

(D) (A) is false but (R) is true
(D) (i) (iii) (ii) (iv)

16

51. Identify the ordered processing 53. Which of the following cannot be
steps in fabrication of integrated
obtained from an X-ray crystallography
circuits :
study ?
(A) Diffusion, Oxidation, Chemical

vapour deposition, Photo- (A) Packing arrangements
lithography, Metallization
(B) Spacing between two parallel
(B) Oxidation, Diffusion, Chemical

vapour deposition, Photo- atomic rings

lithography, Metallization
(C) Vibration frequency of a
(C) Chemical vapour deposition,
carbonyl group
Oxidation, Diffusion, Photo-

lithography, Metallization (D) Geometry of hydrogen bonding

(D) Diffusion, Oxidation, Photo-
54. Most of the VLSI foundries specify
lithography, Chemical vapour
Design Rule files. These design rules
deposition, Metallization
however do not specify :
52. In nMOS device, gate material could

be : (A) Line widths

(A) Silicon
(B) Interpattern separations
(B) Polysilicon
(C) Layer colours
(C) Boron

(D) Phosphorus (D) Pattern extensions

17 [P.T.O.

55. In CMOS logic circuits the p-MOS 57. The Fast Fourier Transform

transistor acts as : algorithm exploits properties of the

twiddle factor :
(A) Pull-down network
(A) Symmetry and periodicity
(B) Pull-up network
(B) Convolution and correlation
(C) Short to ground
(C) Linearity and causality
(D) Load
(D) Asymmetry and linearity
56. The circuit diagram shown in figure
58. ASSERTION (A) : Epitaxy refers
represents :
to the deposition of a crystalline

overlayer on a crystalline substrate.

REASON (R) : An epitaxial layer

cannot be doped during growth

phase.

(A) Both (A) and (R) are true and

(R) is correct explanation of (A)

(B) Both (A) and (R) are true but
(A) Two input CMOS AND gate
(R) is not correct explanation

(B) Two input CMOS NAND gate of (A)

(C) Two input CMOS NOR gate (C) (A) is true but (R) is false

(D) Two input CMOS OR gate (D) (A) and (R) both are false

18

59. Match List-I with List-II :
61. On which of the following principles
List-I
(a) Gate conductor does Klystron operate ?

(b) Masking impurity diffusion
(A) Amplitude modulation
(c) Isolation method
(d) Layout planning (B) Frequency modulation
List-II
(i) SiO2 layer (C) Pulse modulation

(ii) Polysilicon
(D) Velocity modulation
(iii) Stick diagram
(iv) Trench oxidation (LOCOS) 62. DSO cannot be used for :
Codes :
(a) (b) (c) (d) (A) Signal analysis

(A) (ii) (iii) (iv) (i)
(B) Signal monitoring
(B) (iii) (i) (ii) (iv)
(C) (iv) (i) (ii) (iii) (C) Signal digitisation
(D) (ii) (i) (iv) (iii)
60. Identify the correct sequence for (D) Signal generation
implementing sensors in IOT :
63. Duplexer in RADAR system is :
(A) Data acquisition, conversion,
sensing and communication
(A) An oscillator
(B) Sensing, data acquisition,
conversion and communication (B) Microwave switch
(C) Sensing, conversion, data
acquisition and communication (C) An amplifier
(D) Sensing, conversion, communi-
cation and data acquisition (D) Active filter

19 [P.T.O.

64. Which of the following is the
67. The dominant mode of a rectangular
Poisson’s equation ?
(A) 2V = – / wave guide is :
(B) 2V = – 4

(C) 2V = – 4 (A) TE 11
(D) 2V = 0
(B) TE 12
65. The Health status of functioning
heart is recorded as ECG, which is
represented as : (C) TE 10

(A) Current in A
(D) TE21
(B) DC voltage in mV
(C) Pulsed waveform of micro volt
68. Arrange the following microwave
(D) High frequency signal
66. Match List-I with List-II : frequency bands on increasing order
List-I : Number on Display
of frequency :
(a) 1072
(b) 893 (i) L Band
(c) 132
(d) 59705 (ii) S Band
List-II : ADC
(i) 8-bit (iii) C Band

(ii) 10-bit
(iv) X Band
(iii) 12-bit
(iv) 16-bit
(A) (iii), (i), (iv), (ii)
Codes :
(a) (b) (c) (d) (B) (iv), (iii), (ii), (i)
(A) (iii) (i) (ii) (iv)
(B) (iii) (ii) (i) (iv) (C) (ii), (iii), (iv), (i)
(C) (iv) (i) (ii) (iii)
(D) (i) (ii) (iii) (iv) (D) (i), (ii), (iii), (iv)

20

69. Match the following lists : 70. Assertion-Reason type questions :

List I
Assertion (A) :

(a) Tunnel diode
Electromagnetic waves are trans-
(b) Gunn diode
verse in nature.
(c) Reflex klystron
Reason (R) :
(d) TRAPATT
The electric and magnetic fields are
List II
perpendicular to the direction of
(i) Negative Resistance
wave propagation.
(ii) Two cavity
(A) Both (A) and (R) are true and
(iii) Oscillator
(R) is the correct explanation
(iv) Low noise oscillator
of (A)
Codes :

(B) Both (A) and (R) are true but
(a) (b) (c) (d)
(R) is not correct explanation
(A) (i) (iii) (iv) (ii)
of (A)
(B) (i) (iii) (ii) (iv)

(C) (A) is true but (R) is false
(C) (i) (ii) (iii) (iv)

(D) (iv) (i) (ii) (iii) (D) (A) is false and (R) is true

21 [P.T.O.

71. An AM signal is detected using an 73. A frame in video transmission

envelope detector. The carrier system has 800 × 400 pixel grid with

frequency and modulating signal 64 intensity levels per pixel. The

transmission system transmit 360
frequency are 2 MHz and 1 kHz
picture frames per second. The data
respectively. An appropriate value
rate of the system is :
for the time constant of the envelope

detector is : (A) 1382.4 Mb/s

(B) 3686 Mb/s
(A) 2000 s

(C) 691.2 Mb/s
(B) 0.050 s

(D) 7372 Mb/s
(C) 100 s
74. Receiver without automatic gain
(D) 200 s
control is tuned to a strong station,
72. Which of the following is not the
the signal may ................ the later IF
MEMS application ?
and AF stage.

(A) Impact sensor in air bags (A) Cut-off

(B) Face detection (B) Overload

(C) Hall effect proximity sensor (C) Underload

(D) Accelerometer (D) Cut-in

22

75. An eye diagram is an oscillocope 77. In frequency shift keying :

(a) The combined signal in FSK
display in which the ...................... is
modulator generated from two
synchronized to the ..................... .
separate oscillators cannot have

(A) Bit rate, intensity base discontinuities in amplitude.

(b) The combined signal in FSK
(B) Intensity base, time base
modulator generated from two

(C) Time base, bit rate separate oscillators cannot have
discontinuities in phase.
(D) Bit rate, time base
(c) The combined signal in FSK
76. Three sinusoidal signals 2400 Hz, modulator generated from
single oscillator method can
1200 Hz and 800 Hz are sampled
have discontinuities in
at their respective Nyquist rates,
amplitude.
these are encoded with 8 bit words (d) The combined signal in FSK
and time division multiplexed. The modulator generated from
single oscillator method cannot
bit rate for the multiplexed signal
have discontinuities in
is : amplitude.

(A) 35.2 kb/s Options :

(A) (b) and (d)
(B) 105.6 kb/s
(B) (a) and (d)
(C) 352 kb/s
(C) (d) only
(D) 10.56 kb/s (D) (a) and (c)

23 [P.T.O.

78. Match List I with List II and select
79. The main difference between the
the correct answer using codes given

below : thermal noise and shot noise is

List I that :

(a) DSB-SC modulation
(A) Mean square noise component
(b) Amplitude modulation

(c) Frequency modulation is dependent noise bandwidth in

(d) Phase modulation
shot and thermal noise
List II

t (B) Mean noise component is zero
(i) A sin (wct + k m( z) dz)
–

(ii) A sin (wct + km(t)) in both

(iii) k.m(t) A sin (wct)
(C) Shot noise non-uniform
(iv) {1 + km(t)} A sin (wct)

Codes : spectrum in high microwave

(a) (b) (c) (d)
frequency range
(A) (iv) (i) (iii) (ii)

(B) (iii) (iv) (i) (ii)
(D) Shot noise and thermal noise is
(C) (iii) (i) (ii) (iv)
temperature dependent
(D) (iv) (iii) (i) (ii)

24

82. For the following DIAC triggered
80. Which of the following technologies is
circuit the pattern of the current
trigger pulses at gate (IG) will be :
associated with IOT implementation ?

(A) High power drivers

(B) Big data analytics

(C) LTCC

(D) Cryogenics (A)

81. Find maximum operating/switching

frequency of a converter grade SCR
(B)
whose turn on time and turn off time

are 50 s and 150 s respectively.

(A) 20 kHz
(C)

(B) 10 kHz

(C) 5 kHz

(D)
(D) 2 kHz

25 [P.T.O.

85. In two transistor analogy of a
83. In thyristor circuits to isolate control
thyristor, if ‘ ’ is current gain and
part from power section the following
ICBO is the collector leakage current,

method of coupling is used : the expression for anode current ‘IA’

is given by :
(A) Pulse transformer
(A) I A 1IG ICBO1 – ICBO2
1–( 1 2)
(B) High voltage capacitor
(B) I A 1IG ICBO1 ICBO2
1 ( 1 2)
(C) Specialized RC section
2 IG ICBO2 ICBO1
(C) I A
1 – ( 1 – 2)
(D) High speed relay

(D) I A 2 IG ICBO1 ICBO2
1–( 1 2)
84. Field breakdown voltage for silicon

86. The following light source has the
used in power devices is :

best directivity :
(A) 100 kV/cm
(A) Burrus LED

(B) 300 kV/cm
(B) Edge emitting LED

(C) 1 MV/cm
(C) Surface emitting LED

(D) 10 MV/cm (D) Double Heterojunction LED

26

87. The following technique is best 90. Match the following :
suited for low cost optical fibers :
Set I
(A) VAD
(a) Line width
(B) OVD
(b) Directionality
(C) MCVD
(c) Energy
(D) Double crucible

88. The following optical fiber has no (d) Quality factor

effect of impurity in the axis region Set II
in its transmission properties :
(i) Wavelength
(A) Graded index fiber
(ii) Coherence
(B) Single mode fiber
(iii) Energy stored
(C) Step index multimode fiber
(iv) Scattering
(D) Plastic cladded silica fiber

89. In a four level laser system : Codes :

(A) There are four blocks in the (a) (b) (c) (d)

laser system
(A) (i) (iii) (ii) (iv)
(B) Power levels are very high
(B) (iv) (iii) (i) (ii)
(C) Lower lasing level empty
(C) (i) (iv) (ii) (iii)
(D) Pumping power is designed

with four stages (D) (ii) (iv) (i) (iii)

27 [P.T.O.

Q. No. 91 – 95 :
(4) Resolution : The smallest
The static characteristics of an
change in a measured variable
instrument are, in general,
to which an instrument will
considered for instruments which
are used to measure an unvarying respond.
process condition. All the static
(5) Precision : A measure of the
performance characteristics are
obtained by one form or another of consistency or repeatability of

a process called calibration. There measurements i.e., successive
are a number of related definitions reading do not differ. (Precision
(or characteristics), which are
is the consistency of the
described below, such as accuracy,
precision, repeatability, resolution instrument output for a given
errors, sensitivity, etc. value of input).
(1) Instrument : A device or
(6) Expected value : The design
mechanism used to determine
value i.e., the most probable
the present value of the
quantity under measurement. value that calculations indicate

(2) Measurement : The process of one should expect to measure.
determining the amount,
(7) Error : The deviation of the
degree, or capacity by
comparison (direct or indirect) true value from the desired

with the accepted standards of value.
the system units being used.
(8) Sensitivity : The ratio of the
(3) Accuracy : The degree of
change in output (response) of
exactness (closeness) of a
measurement compared to the the instrument to a change of

expected (desired) value. input or measured variable.

28

91. W h i ch of t h e fol l ow i n g i s not an 94. Which of the following has very low

instrument ? precession ?

(A) Mercury thermometer
(A) Fuel gauge in motorbike
(B) PTC thermometer
(B) Meter scale
(C) Thermistor gauge
(C) PID controller
(D) Pyroelectric gauge
(D) Wrist watch
95. Which of the following is highly
92. Which of the following is most
sensitive transducer ?
accurate device for length
(A) Photodiode
measurement ?
(B) Potentiometer
(A) Odometer
(C) Thermocouple
(B) Calorimeter
(D) Thermistor
(C) Micrometer
96. Transient analysis in a control

(D) Vernier calipers system means :

93. Which of the following instruments (A) Subjecting a system for short

has highest resolution ? duration of period

(B) Applying high voltage
(A) Electrometer
momentarily
(B) Micro-ammeter
(C) Analysing system with infinite
(C) 6½ digit multimeter frequency spectrum

(D) Galvanometer (D) A mathematical tool

29 [P.T.O.

97. Derivative control is desirable in a 99. In a control system, what is the

system in which : percentage error in measurement if

(A) Output goes to steady state the variable range is 4.20 mA and

below the set level the measured value is 13 mA with

(B) Value of the controlled variable set point of 10 mA :

changes rapidly
(A) 18.75

(C) Environmental variables play
(B) 20.50
higher role
(C) 24.00
(D) Cost effective design is
(D) 28.75
necessary

100. Disadvantage of an electronic
98. The following is an example for
control system is :
closed loop system :

(A) Large current requirement
(A) Room fan

(B) Air cooler (B) Expensive

(C) Laboratory soldering iron (C) Susceptible to fire risk

(D) Refrigerator (D) Varies with seasonal changes

30

ROUGH WORK

31 [P.T.O.

ROUGH WORK

32