HPSC Polytechnic Lecturer 2022: Lecturer (Technical Education) Screening Test, Electrical Engineering (Advt. No. 11/2021)
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QUESTION BOOKLET
ELECTRICAL ENGINEERING
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A
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Electrical Engineering /7- A
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1. A resistance of 10 is connected 5. The average power delivered to an
in one branch of a linear network. impedance (10 – j 8) ohm by a
The current in this branch is 5 A. current 20 cos(314t + 30°)A is
If this resistor is replaced by 5 , [A] 200 W
the maximum value of the current
[B] 500 W
in this branch can be
[C] 1000 W
[A] 15 A
[D] 2 kW
[B] 10 A
[C] 20 A 6. A circular disc of radius 4 m with a
[D] 25 A charge density s = 12 sin C/m2
is enclosed by surface S, net flux
2. A non-ideal voltage source has a (in C) crossing S is
source impedance ZS with a resistive [A] 0
load, then at what value of load
[B] 2
resistance the maximum power is
transferred to load? [C] 5
[A] Load resistance is equal to [D] 10
source resistance
7. For the signal f (t ) 3sin 8 t
[B] Load resistance is equal to
complex conjugate of ZS 6sin12t sin14 t , the minimum
sampling frequency (in Hz), satisfying
[C] Load resistance is equal to the Nyquist criterion is
magnitude of ZS
[A] 16
[D] Load resistance is equal to
source reactance [B] 24
[C] 28
3. For a series R-L-C circuit at [D] 14
resonance condition, the power
factor of the circuit at upper half 8. If F (z) = (z 2 + z)/(z 2 – 2z + 1) is
power frequency is z-transform of sequence f (k), then
[A] leading the value of f (2) is
[B] lagging [A] 1
[C] unity [B] 3
[D] zero [C] 5
[D] 7
4. In a two-wattmeter method of
power measurement, one of the 9. A system is defined by its impulse
wattmeters will show zero reading response h(n) = 2nu(n – 2). The
when the power factor of load is system is
[A] zero [A] stable and causal
[B] 0·5 [B] causal but not stable
[C] more than 0·5 [C] stable but not causal
[D] unity [D] unstable and non-causal
Electrical Engineering/7- A 2
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10. The ratio of starting to maximum 14. A synchronous motor is operating
torque of an induction motor is 0·5. on no-load at unity power factor. If
If the rotor resistance of the motor the field current is reduced, then
is increased, this ratio
[A] both power factor and current
[A] will remain constant will decrease
[B] will decrease
[B] power factor will decrease
[C] cannot be determined
whereas current will increase
[D] will increase
[C] both power factor and current
11. If a transformer is operated at will increase
rated frequency but at a voltage
less than its rated value, no load [D] power factor will increase
current and iron loss as compared whereas current will decrease
to their rated values will
15. A 3-phase, 4-wire star-connected
[A] increase, decrease respectively
load takes line current of
[B] both decrease
5 90 A , 5 90 A and 5 A. The
[C] decrease, increase respectively neutral current is
[D] both increase
[A] 5 A
12. The no-load speed of a 250 V, [B] 0 A
separately excited DC motor
is 25 radians/s. The armature [C] 10 A
resistance drop and brush drop are
[D] 15 A
neglected. The field current is
kept constant at rated value. The
torque of the motor in N-m for an 16. The power input to an induction
armature current of 10 A is motor is 100 kW when it runs at 2%
slip. The stator losses are assumed
[A] 50
negligible. Rotor copper loss is
[B] 100
[A] 2 kW
[C] 150
[D] 200 [B] 4 kW
13. In an induction motor, the rotor [C] 98 kW
field runs with respect to the [D] 1 kW
stator field at
[A] synchronous speed in the 17. In a thermal power plant, the feed
same direction as the stator water coming to the economiser is
field heated using
[B] the slip speed in the same
[A] HP steam
direction as the stator field
[C] synchronous speed in the [B] direct heat in the furnace
opposite direction as the stator
[C] LP steam
field
[D] zero speed [D] flue gases
Electrical Engineering /7- A 3 [ P.T.O.
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18. The inertia constant of a 100 MVA, 22. For a feedback control system
50 Hz, 4-pole generator is 10 MJ/MVA. with a characteristic equation
If the mechanical input to the
K
machine is suddenly raised from 1 0 , the break-away
s (s 1)(s 3)
50 MW to 75 MW, then the rotor point on real axis as K increases is
acceleration will be equal to
[A] –1·577
2
[A] 22·5 electrical degree/s [B] –0·423
[B] 225 electrical degree/s2 [C] –1·605
2
[C] 125 electrical degree/s [D] –1·005
[D] 12·5 electrical degree/s2
23. The impulse response of an LTI
system is a unit ramp function,
19. The insulation resistance of a 30 km
the transfer function of the system
long underground cable is 10 M.
is
Other things being the same, the
insulation resistance of a 15 km [A] 1/s 2
long cable will be [B] 1/s
[A] 20 M [C] 1
[B] 40 M [D] 2/s3
[C] 5 M 24. The initial slope of Bode plot for a
[D] 10 M transfer function having double
pole at origin is
20. A synchronous generator connected [A] 20 dB/decade
to an infinite bus having Ef = 1·3 pu, [B] –20 dB/decade
XS = 1·1 pu and delivering power
[C] –40 dB/decade
0·6 pu. The reactive power delivered
under this condition is (neglect [D] – 60 dB/decade
resistance of generator)
25. In RH criteria, if all the elements
[A] 0·21 pu in a row are zeros, it indicates
[B] 0·11 pu that roots lie on the
[C] 0·15 pu [A] origin
[B] positive real axis
[D] 0·01 pu
[C] imaginary axis
21. The open-loop transfer function of a [D] negative real axis
unity-gain feedback control system
26. A 0–200 V voltmeter has an accuracy
2 of 2 percent at full-scale reading.
is given by G (s ) , the
(s 1)(s 2) What will be the error (in %) if it
gain margin of the system in dB is
reads 50 V?
[A] zero [A] 1
[B] one [B] 2
[C] five [C] 4
[D] [D] 8
Electrical Engineering/7- A 4
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27. A 10 bit A/D converter is used 32. In a series R-L-C high Q circuit, the
to digitise an analog signal in the current peaks at a frequency
0 to 5 V range. The maximum peak [A] equal to resonant frequency
to peak ripple voltage that can be
[B] greater than the resonant
allowed in the DC supply voltage is
frequency
[A] nearly 100 mV
[C] less than the resonant
[B] nearly 5·0 mV
frequency
[C] nearly 25 mV
[D] None of the above
[D] nearly 75 mV
28. In common emitter amplifier, the Direction (Q. Nos. 33 and 34) : In the
un-bypassed emitter resistance circuit shown below, the three voltmeter
provides readings are V1 = 220 V, V 2 = 122 V and
V3 = 136 V :
[A] current-series feedback
[B] voltage-shunt feedback
[C] negative voltage feedback
[D] positive current feedback
29. A single-phase full converter with
R-L load can be operated in
[A] first quadrant only
[B] first and second quadrants only
[C] first and fourth quadrants only
[D] all four quadrants 33. The power factor of the load is
[A] 0·45
30. A single-phase full-bridge VSI
operating in square-wave mode [B] 0·50
supplies a purely inductive load. If [C] 0·55
the inverter time period is T, then [D] 0·60
the time duration for which each
of the feedback diodes conduct in 34. The RL = 5 , the approximate power
a cycle is consumption of the load is
[A] T [A] 700 W
[B] T/4 [B] 750 W
[C] T/2 [C] 800 W
[D] T/8 [D] 850 W
31. A DC-DC boost converter, operating
35. A capacitor used for power factor
in continuous conduction mode, is
correction in single-phase circuit
supplying a load at 400 V with
decreases
input voltage of 200 V. The off-time
of the switch is 20 s. The operating [A] the power factor
frequency of the converter is [B] the line current
[A] 25 kHz [C] both the line current and the
[B] 50 kHz power factor
[C] 100 kHz [D] the line current and increases
[D] 200 Hz the power factor
Electrical Engineering /7- A 5 [ P.T.O.
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36. The v -i characteristics of an element 40. The energy stored in the magnetic
is shown in the given figure. field of a solenoid 30 cm long and
3 cm in diameter wound with
1000 turns of wire carrying current
of 10 A is
[A] 0·015 J
[B] 0·15 J
[C] 0·5 J
[D] 1·15 J
The element is
41. Consider the function
[A] non-linear, active, non-bilateral 5
[B] linear, active, non-bilateral F (s ) 2
s(s 3s 1)
[C] non-linear, passive, non-bilateral
where F(s) is Laplace transform of
[D] non-linear, active, bilateral
function f (t). The initial value of f (t )
37. Two heaters rated at 1000 W, 250 V is
each, are connected in series
[A] 5
across a 250 V, 50 Hz AC mains.
The total power drawn from the [B] 5/2
supply would be [C] 5/3
[A] 1000 W [D] 0
[B] 500 W
42. Given two continuous time signals
[C] 250 W
x(t) = e–t and y(t) = e–2t which exist for
[D] 2000 W
t > 0, the convolution z(t) = x(t) * y(t) is
38. A circular loop has its radius
[A] e t e 2t
increasing at the rate of 2 m/s.
The loop is placed perpendicular to [B] e 3t
a constant magnetic field of [C] e t
0·1 Wb/m2. When the radius of the
loop is 2 m, the e.m.f. induced in [D] e t e 2t
the loop will be
43. Match the following :
[A] 0·8V
[B] 0·4V List—I List—II
[C] 0·2V 1
n
[D] zero a. Even Signal 1. x (n ) u(n )
4
39. The mutual inductance between b. Causal Signal 2. x (–n ) = x(n)
two coupled coils is 10 mH. If the c. Periodic Signal 3. x (t)u (t )
turns in one coil are doubled and d. Energy Signal 4. x(n ) = x(n + N)
that in the other are halved, then Codes :
the mutual inductance will be a b c d
[A] 5 mH [A] 2 3 4 1
[B] 10 mH [B] 1 3 4 2
[C] 14 mH [C] 2 4 3 1
[D] 20 mH [D] 1 4 3 2
Electrical Engineering/7- A 6
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44. Let x (t ) X ( j ) be Fourier transform 48. The armature resistance of a
pair. The Fourier transform of the PMDC motor is 0·8 ohm. At no-load,
signal x(5t – 3) in terms of X( j ) is the motor draws 1·5 A from a
given as supply voltage of 25 V and runs at
1500 r.p.m. The efficiency of the
j 3
1 5 j motor while it is operating on load
[A] e X
5 5 at 1500 r.p.m. drawing a current of
3·5 A from the same source will be
j 3
1 5 j [A] 48%
[B] e X
5 5 [B] 57·1%
[C] 59·2%
1 j 3 j
e X
[C]
5 5 [D] 88·8%
1 j 3 j 49. The low voltage winding of a
[D] e X
5 5 400/230 V single-phase 50 Hz
transformer is to be connected to a
45. The output y(t ) of a causal 25 Hz supply. In order to keep the
LTI system described by magnetization current at the same
(s 1) level in both the cases, the voltage
H (s ) 2 for a given input
s 2s 2 at 25 Hz should be
t
x (t ) e u (t ) is [A] 230 V
t
[A] y (t ) e sin t u(t ) [B] 460 V
(t 1) [C] 115 V
[B] y (t ) e sin(t 1) u (t 1)
[D] 65 V
[C] y (t ) sin(t 1) u (t 1)
t 50. A 50 Hz transformer having equal
[D] y (t ) e cos t u (t )
hysteresis and eddy-current losses
at rated excitation is operated at
46. Which of the following losses
45 Hz at 90% of its rated voltage.
occurring in a DC machine varies
Compared to rated operating point,
significantly with the load?
the core losses under this condition
[A] Armature copper loss [A] are reduced by 10%
[B] Shunt field copper loss [B] are reduced by 19%
[C] Magnetic or iron loss [C] are reduced by 14·5%
[D] Mechanical loss [D] remain unchanged
51. The phasor diagram of a
47. The armature core of a DC
transformer on load can be drawn
machine gets overheated due to
only if you know
[A] copper loss occurring in the
[A] equivalent circuit parameters
armature winding only
of the transformer
[B] eddy-current loss only [B] load current
[C] hysteresis loss only [C] load p.f.
[D] All of the above [D] All of the above
Electrical Engineering /7- A 7 [ P.T.O.
Text of page 8
52. Consider the circuit shown in the 54. When the load on a transmission
given figure. line is equal to the surge impedance
loading
[A] the receiving-end voltage is
less than the sending-end
voltage
[B] the sending-end voltage is less
than the receiving-end voltage
[C] the receiving-end voltage is
equal to the sending-end
voltage
[D] None of the above
55. A distance relay is said to be
For maximum power transfer to inherently directional if its
the load, the primary to secondary characteristic on R-X diagram
turn-ratio may be [A] is a straight line off-set from
the origin
[A] 9 : 1
[B] is a circle that passes through
[B] 3 : 1 the origin
[C] 1 : 3 [C] is a circle that encloses the
origin
[D] 1 : 9
[D] Always a separate directional
relay is required
53. Match the machine characteristics
56. In a PMMC instrument, the central
given in List—I with their
spring stiffness and the strength
corresponding quantities given in
of the magnet decrease by 0·04%
List—II :
and 0·02% respectively due to a
List—I List—II rise in temperature by 1 °C. With a
rise in temperature of 10 °C, the
(Machine characteristics) (Quantity)
instrument reading will
a. Open circuit 1. Pf vs If [A] increase by 0·2%
characteristic [B] decrease by 0·2%
b. V-curve 2. Ea vs Ia [C] increase by 0·6%
[D] decrease by 0·6%
c. Internal 3. Eg vs If
characteristics 57. A 50 Hz, 3-phase synchronous
d. Inverted V-curve 4. Ia vs If generator has inductance per
phase of 15 mH. The capacitance
Codes :
of generator and circuit breaker is
a b c d 0·002 F. What is its natural
[A] 3 1 2 4 frequency of oscillation?
[B] 2 4 3 1 [A] 29 kHz
[B] 2·0 kHz
[C] 3 4 2 1
[C] 290 kHz
[D] 2 1 3 4 [D] 29 MHz
Electrical Engineering/7- A 8
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58. A 3-phase alternator generating 60. A PMMC type ammeter and a
unbalanced voltages is connected moving-iron type ammeter are
to an unbalanced load through a connected in series in a resistive
3-phase transmission line as circuit fed from output of a half-
shown in the given figure. wave rectifier voltage source. If
the moving-iron type reads 5 A,
the PMMC type instrument is
likely to read
[A] 0 A
[B] 2·5 A
[C] 3·18 A
[D] 5 A
The neutral of the alternator and the
star-point of the load are solidly 61. In a digital voltmeter, input signal
grounded. The phase voltages of is integrated for a duration of 500
the alternator are Ea 10 0 V , clock cycles. To eliminate the
effect of 100 Hz noise present in
Eb 90 V , Ec 120 V . The
the signal, what is the maximum
positive sequence component of
clock frequency?
the load current is
[A] 5 kHz
[A] 1·310 107 A [B] 50 kHz
[B] 0·332 120A [C] 100 kHz
[C] 0·996 120 A [D] 250 kHz
[D] 3·510 81 A 62. Consider the following statements
in connection with DAC :
59. Which of the following factors limits 1. The resolution of a 10-bit DAC
the deflection of the pointer of a is nearly equal to 0·1% of its
PMMC instrument to about 90o? full-scale range.
1. Its damping mechanism 2. The linearity of a DAC depends
principally on the accuracy of
2. Linearity of the magnetic field the resistors used.
in which the coil moves
3. The R-2R ladder type DAC
3. Control spring arrangement requires less number of
resistors compared to weighted-
4. Shape of the pole shoe of the
resistor type of DAC.
horseshoe magnet
4. The output of a DAC should be
Select the correct answer using monotonic.
the codes given below : Which of the above statements are
[A] Only 1 and 3 correct?
[A] 1, 2 and 3
[B] Only 2 and 4
[B] 1, 2 and 4
[C] Only 2 and 3 [C] 2, 3 and 4
[D] Only 1 and 4 [D] 1, 3 and 4
Electrical Engineering /7- A 9 [ P.T.O.
Text of page 10
63. The current through the current 65. The AC bridge shown in the given
coil of a wattmeter is given by figure is used to measure the
i = (1 + 2sin t) A and the voltage impedance Z. If the bridge is
across the pressure coil is balanced for oscillator frequency
v = (2 + 3 sin 2 t) V. The wattmeter f = 2 kHz, the impedance Z will be
will read
[A] 8·00 W
[B] 5·05 W
[C] 2·0 W
[D] 1·0 W [A] (260 + j 0)
[B] (0 + j 200)
64. A single-phase load is connected [C] (260 – j 200)
between R and Y terminals of a [D] (260 + j 200)
415 V, symmetrical 3-phase,
4-wire system with phase
sequence RYB. A wattmeter is 66. Match Boolean Logic Function
connected in the system as shown given in List—I with their
in the given figure. The power corresponding Inverse of Function
factor of the load is 0·8 lagging. given in List—II :
The wattmeter will read
List—I List—II
(Boolean Logic (Inverse of
Function) Function)
P. ab + bc + ca + abc 1. a ( b c )
Q. ab ab c 2. ab bc c a
R. a + bc 3. (a b )c
S. (a b c ) (a b c ) 4. abc abc abc
(a b c )
[A] +597 W Codes :
P Q R S
[B] –795 W [A] 3 2 1 4
[B] 2 3 1 4
[C] +795 W
[C] 3 2 4 1
[D] –597 W [D] 2 3 4 1
Electrical Engineering/7- A 10
Text of page 11
67. A multistage amplifier has a low- 69. The input voltage given to a
pass response with three real converter is vi 100 2 sin(100 t )V .
poles at s = – 1, – 2 and 3. The The current drawn by the converter
approximate overall bandwidth B of is
the amplifier will be given by
ii [10 2 sin(100 t /3)
[A] B 1 2 3
5 2 sin(300 t /4)
1 1 1 1 2 2 sin(500 t /6)] A
[B] B
1 2 3
The input power factor of the
[C] B (1 2 3 ) 1/3 converter is
[A] 0·31
[D] B 12 22 23 [B] 0·44
[C] 0·5
[D] 0·71
68. An astable multivibrator circuit
using IC 555 timer is shown below. 70. Commutation overlap in the phase-
Assume that the circuit is oscillating controlled AC to DC converter is
steadily. due to
[A] load inductance
[B] harmonic content of load
current
[C] switching operation in the
converter
[D] source inductance
71. Chopper circuits are used to
control the speed of DC motors
which are fed from fixed DC
voltage sources. Variable voltage
output can be obtained by which of
the following methods?
1. Varying the ‘on’ to ‘off’ time
ratio
2. Adjusting the wave shape
3. Adjusting the frequency of
switching
The voltage VC across the capacitor 4. Using a saturable core reactor
varies between in series with the motor
[A] 3 V to 5 V [A] 1 and 2
[B] 3 V to 6 V [B] 1 and 3
[C] 3·6 V to 6 V [C] 2 and 3
[D] 3·6 V to 5 V [D] 2 and 4
Electrical Engineering /7- A 11 [ P.T.O.
Text of page 12
72. In AC motor control, the ratio of 76. A circular coil of 160 turns has a
voltage-to-frequency is maintained radius of 4·5 cm. The coil carries a
at constant value to current I of 0·6 amp. The magnitude
[A] make maximum use of of the magnetic field is
magnetic circuit
[B] make minimum use of [A] 1·34 × 10–3 T
magnetic circuit
[C] maximize the current drawn [B] 13·4 × 10–3 T
from the supply to provide
torque [C] 0·134 × 10–3 T
[D] provide maximum pull-out
torque [D] 134 × 10–3 T
73. The voltage across the terminals
AB for the circuit shown in the 77. A system with input x(t) and output
given figure is y(t) is described by the relation
y(t) = t2 x(t). The system is
[A] non-linear and time-varying
[A] 5 V [B] non-linear and time-invariant
[B] 10 V
[C] linear and time-varying
[C] 12 V
[D] 20 V
[D] linear and time-invariant
74. What inductance will give the same
reactance as a capacitor of 2 F,
when both are at 50 Hz? 78. Which of the following equivalence
between Z-transform and Laplace
[A] 5 H
transform holds?
[B] 25 H
[C] 50 H [A] The left-half of the s-plane
[D] 100 H maps into the interior of the
unit circle in the z-plane
75. The total power in a 3-phase
system, whether star or delta [B] The right-half of the s-plane
connected, is given by maps into the exterior of the
unit circle in the z-plane
[A] 3 V L I L cos
[B] 3 V L I L cos [C] The imaginary axis of s-plane
1 maps into the boundary of unit
[C] V L I L cos
3 circle in the z-plane
1
[D] V L I L cos
3 [D] All of the above
Electrical Engineering/7- A 12
Text of page 13
79. The second harmonic component 82. In a 50 kVA, 11 kV/400 V transformer,
of the periodic waveform given in the iron and copper losses are 500 W
the figure has an amplitude of and 600 W respectively under rated
conditions. The efficiency on unity
power factor at full load will be
[A] 96·85%
[B] 97·85%
[C] 99%
[D] 98%
[A] 0
[B] 1 83. A 3300/300 V single-phase trans-
former gives 0·6 A and 60 W as
[C] 2/ ammeter and wattmeter readings
[D] 5 when supply is given to the low
voltage winding and high voltage
winding is kept open. The power
80. Non-linear system cannot be factor of no load current is
analysed by Laplace transform
because [A] 0·44
[A] it has no zero initial conditions [B] 0·38
[B] superposition law cannot be
applied [C] 0·33
[C] non-linearity is generally not [D] 0·35
well defined
[D] All of the above
84. Two transformers of identical
voltages but of different capacities
81. If rated DC voltage is applied are operating in parallel. For
instead of AC to the primary of a satisfactory load sharing
transformer, then
[A] secondary of transformer will [A] impedances must be equal
burn
[B] per-unit impedances must be
[B] primary of transformer will equal
burn
[C] secondary voltage will be [C] per-unit impedances and X/R
excessively high ratios must be equal
[D] there will be no secondary [D] impedance and X/R ratios
voltage must be equal
Electrical Engineering /7- A 13 [ P.T.O.
Text of page 14
85. The armature current for a DC 89. If in a transmission line, resistance
motor is calculated by which of the and inductance are found to be
following formulas, where equal and regulation appears to be
V = supply voltage (in volts), zero, then the load will
Eb = back e.m.f. (in volts) and
[A] have unity power factor
Ra = armature resistance?
[B] have zero power factor
V Eb
[A] I a
Ra [C] be 0·707 leading
V Eb [D] be 0·807 leading
[B] I a
Ra
V 2Eb
[C] I a 90. In load flow analysis, the load
Ra connected at a bus is represented
V 2Eb as
[D] I a
Ra [A] constant current drawn from
the bus
86. The speed at which a 6-pole
alternator should be driven to [B] constant impedance connected
generate 50 cycle per second is at the bus
[A] 1500 r.p.m. [C] voltage and frequency
[B] 1600 r.p.m. dependent source at the bus
[C] 1200 r.p.m. [D] constant real and reactive
power drawn from the bus
[D] 1000 r.p.m.
87. The best location of power factor 91. A car is running at a constant
correction equipment to be installed speed of 50 km/hr. Which of the
on the transmission line is at the following is the feedback element
[A] sending end for the driver?
[B] receiving end [A] Clutch
[C] middle of the line [B] Eyes
[D] quarter of the line [C] Needle of the speedometer
[D] Steering wheel
88. A medium line with parameters A, B,
C and D is extended by connecting a
short line of impedance Z in series. 92. Differentiator is usually not a part
The overall ABCD parameters of of a control system because
the series combination will be
[A] it reduces the gain margin
[A] A, AZ, C + D/Z, D
[B] A, AZ + B, C, CZ + D [B] it increases error
[C] A + BZ, B, C + DZ, D [C] it increases input noise
[D] AZ, B, C/Z, D [D] it reduces damping
Electrical Engineering/7- A 14
Text of page 15
93. The phase lead compensation is 97. Transistor can be used as an
used to amplifier when it is operated in
[A] increase rise time and decrease [A] saturation region
overshoot [B] cut-off region
[B] decrease both rise time and [C] active region
overshoot [D] both saturation and cut-off
[C] increase both rise time and regions
overshoot
[D] decrease rise time and increase
98. An amplifier without feedback has
overshoot
a gain of 1000. What is the gain
with negative feedback of 0·009?
94. A moving coil instrument gives
[A] 900
full-scale deflection with a current
of 100 mA when potential difference [B] 125
across its terminals is 50 mV. The [C] 100
shunt resistance to enable the [D] 10
instrument to read up to 100 A is
[A] 10
99. The output Y of the logic circuit
[B] 8 shown in the given figure is
[C] 6
[D] 5·005 × 10–4
95. A digital voltmeter has a read
outrange from 0 to 9999 counts.
When full-scale reading is
9·999 V, the resolution of the full-
[A] 1
scale reading is
[B] 0
[A] 0·001
[C] X
[B] 1000
[D] X
[C] 3-digit
[D] 1 mV
100. The applied sine voltage to SCR is
Vm = 200 V and R = 10 . If the gate
96. A CRO screen has ten divisions on
trigger lags the AC supply by 120°,
the horizontal scale. If a voltage
then the average load current is
signal 5sin(314t 45) is examined
with a line base setting of 5 msec/div, 10
[A] A
then the number of cycles of signal
displayed on the screen will be 5
[B] A
[A] 0·5
[B] 2·5 5
[C] A
[C] 5
15
[D] 10 [D] A
Electrical Engineering /7- A 15 [ P.T.O.
Text of page 16
SPACE FOR ROUGH WORK
Electrical Engineering/7- A 16 LLL22/7—372×4
Text of page 1
Answer Key - Electrical Engineering
Held on 11.06.2022
Series 'A'
Q.No. Ans Q.No. Ans Q.No. Ans Q.No. Ans
1 B 26 D 51 D 76 A
2 C 27 B 52 B 77 C
3 B 28 A 53 C 78 D
4 B 29 C 54 C 79 A
5 D 30 B 55 B 80 X
6 A 31 A 56 A 81 B
7 D 32 A 57 A 82 B
8 C 33 A 58 X 83 C
9 B 34 B 59 B 84 C
10 D 35 D 60 C 85 A
11 B 36 A 61 B 86 D
12 B 37 B 62 B 87 B
13 D 38 A 63 C 88 B
14 B 39 B 64 D 89 C
15 A 40 B 65 A 90 D
16 A 41 D 66 B 91 C
17 D 42 A 67 B 92 C
18 B 43 A 68 B 93 B
19 A 44 A 69 B 94 D
20 B 45 A 70 D 95 D
21 D 46 A 71 B 96 B
22 B 47 D 72 A 97 C
23 A 48 A 73 B 98 C
24 C 49 C 74 A 99 A
25 C 50 C 75 B 100 B
Text of page 2
Answer Key - Electrical Engineering
Held on 11.06.2022
Series 'B'
Q No. Ans Q No. Ans Q No. Ans Q No. Ans
1 A 26 D 51 D 76 C
2 D 27 B 52 A 77 B
3 B 28 B 53 B 78 B
4 B 29 D 54 A 79 C
5 C 30 B 55 B 80 D
6 D 31 A 56 B 81 A
7 C 32 A 57 D 82 B
8 C 33 D 58 A 83 B
9 B 34 B 59 A 84 B
10 D 35 A 60 A 85 B
11 D 36 B 61 A 86 D
12 B 37 D 62 A 87 B
13 C 38 B 63 D 88 A
14 C 39 A 64 A 89 B
15 A 40 C 65 C 90 A
16 B 41 C 66 C 91 B
17 B 42 D 67 D 92 A
18 C 43 B 68 B 93 C
19 B 44 A 69 C 94 D
20 B 45 C 70 C 95 A
21 D 46 B 71 B 96 X
22 A 47 A 72 A 97 B
23 D 48 A 73 A 98 B
24 C 49 A 74 X 99 C
25 B 50 B 75 B 100 C
Text of page 3
Answer Key - Electrical Engineering
Held on 11.06.2022
Series 'C'
Q No. Ans Q No. Ans Q No. Ans Q No. Ans
1 A 26 D 51 A 76 B
2 B 27 C 52 A 77 D
3 B 28 C 53 D 78 A
4 B 29 B 54 B 79 A
5 B 30 D 55 A 80 A
6 D 31 D 56 B 81 A
7 B 32 B 57 D 82 A
8 A 33 C 58 B 83 D
9 B 34 C 59 A 84 A
10 A 35 A 60 C 85 C
11 B 36 B 61 C 86 C
12 A 37 B 62 D 87 D
13 C 38 C 63 B 88 B
14 D 39 B 64 A 89 C
15 A 40 B 65 C 90 C
16 X 41 D 66 B 91 B
17 B 42 A 67 A 92 A
18 B 43 D 68 A 93 A
19 C 44 C 69 A 94 X
20 C 45 B 70 B 95 B
21 A 46 D 71 D 96 C
22 D 47 B 72 A 97 B
23 B 48 B 73 B 98 B
24 B 49 D 74 A 99 C
25 C 50 B 75 B 100 D
Text of page 4
Answer Key - Electrical Engineering
Held on 11.06.2022
Series 'D'
Q No. Ans Q No. Ans Q No. Ans Q No. Ans
1 A 26 B 51 D 76 B
2 B 27 B 52 B 77 B
3 A 28 C 53 B 78 D
4 B 29 D 54 C 79 B
5 B 30 A 55 D 80 A
6 D 31 B 56 C 81 A
7 A 32 B 57 C 82 D
8 A 33 B 58 B 83 B
9 A 34 B 59 D 84 A
10 A 35 D 60 D 85 B
11 A 36 B 61 B 86 D
12 D 37 A 62 C 87 B
13 A 38 B 63 C 88 A
14 C 39 A 64 A 89 C
15 C 40 B 65 B 90 C
16 D 41 A 66 B 91 D
17 B 42 C 67 C 92 B
18 C 43 D 68 B 93 A
19 C 44 A 69 B 94 C
20 B 45 X 70 D 95 B
21 A 46 B 71 A 96 A
22 A 47 B 72 D 97 A
23 X 48 C 73 C 98 A
24 B 49 C 74 B 99 B
25 C 50 A 75 D 100 DPage 1 of 16
Source: Haryana Public Service Commission. Question paper published by Haryana Public Service Commission.