| Post Name | Assistant Engineer (Electrical) |
|---|---|
| Department | Kerala State Electricity Board Ltd |
| Question Paper Code | 044/2026/OL |
| Category Code | 378/2025 |
| Date of Test | 17 March 2026 |
| Exam Type | Online Examination |
| Total Questions | 100 |
1
What are the values of R1 and R2 in the circuit shown below?
Answer
A. 12W and 4W
2
A sinusoidal voltage is represented as v = 141.4 sin(628t − π/4). The RMS value, frequency and phase angle are, respectively
Answer
B. 100, 100, -45°
3
An impedance Z = (6 + 8j) Ω is connected across a 200 V, 50 Hz supply. The power factor and current are
Answer
C. 0.6 lagging, 20 A
4
The resonant frequency in RLC series circuit is
Answer
C. f₀ = 1/(2π√(LC))
5
The bandwidth of a series RLC circuit is
Answer
D. R/(2πL)
6
The mutual inductance between two tightly coupled coils is 1 H. The turns of one of the coils is halved and those of the offer is doubled. The value of the mutual inductance now becomes
Answer
B. 1 H
7
For the figure below, the inductance matrix is given by. Figure: three series-coupled coils have self-inductances 2 H, 1 H and 3 H; the shown mutual inductances are 3 H between coils 1–2, 2 H between coils 2–3, and 1 H between coils 1–3, with dot polarities as drawn.
Answer
B. [[2, −3, 1], [−3, 1, −2], [1, −2, 3]]
8
For the square wave shown below, the form factor is
Answer
C. 1
9
In the circuit below, the resistance load at 'ab' for maximum power output is. Figure: a 2∠0° V AC source is in series with an inductive reactance j2 Ω; a capacitive reactance −j Ω is connected across output terminals a-b.
Answer
D. 2 Ω
10
Determine equivalent resistance between terminals A and B in the network below. Figure: an outer triangular network has A–top = 1 Ω, top–B = 3 Ω and A–B = 1 Ω; an inner star connects its centre to A through 1 Ω, to the top through 3 Ω, and to B through 3 Ω.
Answer
B. 2/3 Ω
11
Assertion (A) : A time-varying magnetic field produces electric fields. Reason (R) : When the magnetic flux linking a circuit is varied, an emf is induced in the circuit .
Answer
A. Both A and R are individually true, but R is not the correct explanation of A
12
The magnetic field strength due to a current of 2 A flowing in a coil of 180 turns wound uniformly over a wooden ring having a mean circumference of 600 mm and a uniform cross-sectional area of 500 mm2 is
Answer
D. 600 A/m
13
Which of the following materials requires the lowest magnetic field strength to magnetise it?
Answer
A. Nickel
14
If a magnetic flux of 200mWb passing through a coil of 1200 turns is reversed in 0.1 s, the average value of emf induced in the coil is
Answer
B. 4.8 V
15
The magnitude of the induced emf in a conductor depends upon
Answer
D. Rate of change of flux linkage
16
Assertion (A) : For ferromagnetic materials, the relative permeability varies according to the magnetic field strength. Reason (R) : The value of the relative permeability of a ferromagnetic material is not a constant.
Answer
A. Both A and R are true and R is the correct explanation of A
17
The emf generated in the axle of a car travelling at 22 m/s, the length of the axle is 1 m, and the vertical component of the Earth's magnetic field is 40mT
Answer
C. 880 μV
18
A conducting loop is placed in a magnetic field with its plane perpendicular to the field. An emf is induced in the loop if
Answer
C. it is rotated about a diameter
19
Which of the following statements is/are not true about series and parallel magnetic circuits with composite materials?
Answer
B. in a parallel magnetic circuit, the total ampere turns required to create a given flux is the arithmetic sum of the ampere turns required for the individual parts of the circuit
20
Match the similarity between magnetic and electric circuits. Column A Column B (a) Conductance (I) Magnetic flux (b) Current (II) Magnetomotive force (c) Electromotive force (III) Reluctance (d) Resistance (IV) permeance
Answer
D. (a)-(IV), (b)-(I), (c)-(II), (d)-(III)
21
In a three-phase, 8-pole induction motor, the stator current frequency is 50 Hz and the rotor current frequency is 5 Hz. Determine the speed of the motor in rpm.
Answer
B. 675
22
A 6-pole lap-wound armature rotates at 300 rpm and is required to generate 240 V. The useful flux per pole is 40 mwb. If the armature has 120 slots, determine the number of conductors per slot.
Answer
C. 10
23
When operating at constant mechanical load, if the field excitation of a synchronous motor is reduced below its normal value, the motor will
Answer
D. Draw more current at lagging power factor
24
Voltage regulation of a single-phase transformer is zero when load power factor is
Answer
B. Leading
25
A 10 kVA transformer has full load copper loss of 1600 watts and iron loss of 900 watts. At what percentage of load, the transformer will have maximum efficiency?
Answer
A. 75%
26
A field excitation of 10 A in an alternator result in an armature current of 200 A in short circuit and a terminal voltage of 1000 V on open circuit. The magnitude of the internal voltage drop within the machine at a load current of 50 A is
Answer
C. 250 V
27
If the excitation of a synchronous condenser is increased, it will
Answer
B. Supply reactive power
28
In a DC series motor, if the armature current is reduced to 60% of its original value, the torque of the motor will be reduced by
Answer
D. 64%
29
A 6-pole DC generator has 24 coils arranged in a single-layer lap winding. What is the pole pitch?
Answer
C. 8
30
A CNC machine requires open-loop position control without using feedback and must be able to maintain a firm holding torque at standstill. Which motor is most suitable for this application?
Answer
B. Stepper motor
31
If the 8085 executes the instruction MOV M, A, which addressing mode is being utilized, and how many T-states are typically required for this specific instruction?
Answer
C. Register Indirect Addressing; 7 T-states
32
When converting a 4-bit Binary number to Gray code, which logical operation is primarily utilized and what is the Gray code equivalent of binary 1010?
Answer
B. XOR, 1111
33
What is the Excess-3 code representation of the decimal number 5?
Answer
B. 1000
34
Which digital circuit is known as a ''Data Selector''?
Answer
D. Multiplexer
35
Which of the following Analog-to-Digital Converter is considered the fastest?
Answer
A. Parallel comparator/Flash type
36
What is the function of the Address Latch Enable (ALE) signal in the 8085?
Answer
C. To demultiplex the address and data bus
37
A full adder can be implemented by
Answer
B. Two half adders and one OR gate
38
Which of the following is true for a flip-flop and a Latch?
Answer
B. Flip-flops are edge-triggered, while latches are level-triggered
39
Which of the following internal register in the 8085 Microprocessor is not accessible to the programmer but is essential for holding the opcode during the decode phase
Answer
D. Instruction Register
40
After executing the XRA A instruction, what are the resulting states of the Accumulator and the Carry (CY) and Zero (Z) flags?
Answer
C. A = 00H, CY =0, Z = 1
41
The value of inductance between two parallel conductors of a transmission line increases with _________ in the distance of separation between conductors.
Answer
A. increase
42
_________ of insulator is used in 110 kV transmission lines.
Answer
B. suspension type
43
The rated symmetrical breaking current of a 100 MVA, 11 kV, 3-phase oil circuit breaker is _______ kA.
Answer
C. 5.25
44
___________ is used to protect the transformer against all internal faults.
Answer
D. buchholz relay
45
The leakage reactance referred to the low-voltage side of a 1 kVA, 11/0.4 kV single-phase transformer is 1.72 Ω. Its per-unit leakage reactance is
Answer
B. 0.0108
46
The positive sequence impedance of a fully transposed transmission line is ___________ to its negative sequence impedance.
Answer
A. equal
47
The kinetic energy stored in the rotor (in Mega Joule) of a 100 MVA, 2 poles, 50 Hz alternator with a moment of inertia of 60 × 103 kg - m2
Answer
C. 2.9 × 103
48
The convergence is ________ for load flow using Gauss-siedal method.
Answer
B. linear
49
The fault current in the affected line is 125 A when a single line-to- ground fault occurs. The corresponding zero sequence current is ______A.
Answer
D. 41.7
50
The shunt compensators are used to ________.
Answer
Question Cancelled
51
A cascade lag compensation where b > a, Then effect on phase margin and gain margin crossover frequency is
Answer
Question Cancelled
52
T(s) = (k₁s + k₂)/(k₁s⁴ + s³ + k₂s² + s + 1). What is the condition of k₁ and k₂ where the system has two pole on jω-axis
Answer
D. None of the above
53
Consider the characteristic equation P(s) = s⁶ + 5s⁵ + 2s⁴ + 5s³ + 4s² + 15s + 3 = 0. How many poles are in the right half of the s-plane?
Answer
B. 2 poles
54
For a closed-loop system where G(s) = K/(s+2) and H(s) = 2/(s+4), what value of K yields zero steady-state error for a unit-step input?
Answer
Question Cancelled
55
For a second order system with the closed loop The settling time for 2% band in second is
Answer
D. 4
56
Effect of adding a pole to the forward path Transfer function to make.
Answer
A. the closed loop less stable while decreasing the bandwidth
57
The system with the transfer function is operated in closed loop with unity feedback, the closed loop system
Answer
C. unstable
58
The system with the transfer function
Answer
C. Magnitude is 0db and linear phase
59
A negative feedback system is characterized by . The number of breakaway point in the root locus plot is
Answer
B. 1
60
The steady state error for type 1 system for a unit ramp input is
Answer
C. 1/Kᵥ
61
In the circuit shown, the load and stray inductances are negligible and the thyristor is operated at 2 kHz. If the required dv/dt is 100 V/μs and discharge current is limited to 100 A, determine R_s.
Answer
B. 2 Ω
62
Find the slew rate if I_Q = 20 μA and C_X = 50 pF, where I_Q is bias current and C_X is compensating capacitance.
Answer
D. 0.4 V/μs
63
The frequency at which the open-loop voltage gain falls to unity is defined as
Answer
C. Unity-gain bandwidth
64
In the following circuit, circuit current equation will be, (after turning on SCR). Figure: a sinusoidal source Vₘ sin ωt, SCR T, inductor L and resistor R form a series circuit. Note: A is a constant.
Answer
C. (Vₘ/Z) sin(ωt−θ) + Ae⁻⁽ᴿ/ᴸ⁾ᵗ
65
A half wave rectifier delivers pure sinusoidal current during the positive half cycles and zero during negative half cycles. How long it will take to pass a change of 'Q' Ah, if the r.m.s. current is '10π' A. Assume conduction over full positive half cycles.
Answer
C. Q/20 Hrs
66
In a 3j controlled bridge rectifier with an increase of over lap angle, the output DC voltage will be
Answer
A. decreases
67
A 3φ fully controlled converter is feeding power into DC load at a constant current 150 A. The rms current through all thyristors will be
Answer
C. 150/√3 A
68
The maximum current through the following circuit is. Figure: a DC source V drives a series loop containing diode D, capacitor C and inductor L.
Answer
C. V√(C/L)
69
In a three phase inverter, the ratio between third order and fifth order harmonics across the line voltage will be, [Note : the inverter is operating under 180 degree conduction mode with star connected load]
Answer
A. 0
70
In which PWM, battery utilization will be better
Answer
A. SVPWM
71
Which measurement standards are not available for measurement the national Laboratory?
Answer
Question Cancelled
72
An indicating instrument (voltmeter) and an integrating instrument (energy meter) in a dynamic electrical system have different applications. Which scenario best illustrates this?
Answer
C. An indicating instrument detects transient voltage spikes, while an integrating instrument bills cumulative energy use.
73
The scale of a moving iron instrument follows :
Answer
D. Square law
74
A moving coil ammeter has a coil resistance of Rm = 2 ohm, and its full-scale deflection current is If = 5 mA. The instrument is designed to measure currents up to 100 A. To accomplish this, a shunt resistor is connected in parallel with the moving coil. Which of the following is the most suitable value of the shunt resistor?
Answer
B. 0.1 mΩ
75
Which of the following are the characteristics of the pressure (voltage) coil in a dynamometer wattmeter?
Answer
A. High resistance connected in parallel
76
Among the following statements, which is always correct in the two- wattmeter method of three phase power measurement?
Answer
D. Algebraic sum of two readings gives active power
77
What is the power factor angle in a balanced three-phase system that is measured using the two-wattmeter method, where both wattmeter readings are positive and equal?
Answer
A. φ = 0°
78
In an induction-type single-phase energy meter, the driving torque is directly proportional to which electrical quantity?
Answer
C. Instantaneous power
79
Which one among is not correct with digital energy meters over traditional analog induction-type meters?
Answer
B. Lower cost and simpler construction
80
The velocity of electrons striking the fluorescent screen in a Cathode Ray Tube (CRT) is primarily determined by :
Answer
C. Accelerating Anode potential in a Cathode Ray Oscilloscope
81
The transfer function of a first-order hold circuit for a sampling period of 0.1 sec is given by
Answer
A. (10+s)((1−e⁻⁰·¹ˢ)/s)²
82
For a band-limited signal x(t) with X(jω) = 0 for |ω| ≥ 2, x(t) is uniquely determined by samples x(nT), where n = …, −2, −1, 0, 1, 2, … and ωₛ = 2π/T, if:
Answer
D. ωₛ ≥ 4
83
If a discrete-time signal, x(n) is described by n n -2 -1 0 1 2 x(n) -5 -4 0 4 5 and also x(n) = 0, n < -2 and n > 2, then x(n) is
Answer
A. an odd signal
84
If x(t) and y(t) are the input and output of a system and y(t) = x⁴(t) = 0.5x(t), then the system is
Answer
C. nonlinear and time-invariant
85
If r(t) and u(t) represents the unit ramp and unit step signal respectively, then for a signal, y(t) = r(t) u(t) which among the following best describes it
Answer
B. y(t) is an aperiodic signal
86
In the following figure a continuous-time signal, x(t) vs time (t) in seconds is represented. If so, the signal x(t) can also be represented using unit step signal, u(t) as
Answer
D. 4u (t -2) - 4u(t - 4)
87
If x(n) and y(n) represents the input and output of a discrete-time system respectively and the input-output relationship of the system is given by y(n) = (n -1) x(n) + 4 then the system is
Answer
C. non-linear and causal
88
If Figure (a), represents a discrete unit impulse, d(n) as shown then signal, y(n) in figure (b) can be expressed as
Answer
A. d(n + 0.4) + d(n - 0.5)
89
Which of the following statement about the signal, x(t) shown in figure is correct
Answer
D. the total energy of the signal is finite and time-averaged power is zero
90
Which statement regarding the unit impulse function δ(t) is correct?
Answer
C. Impulse function is even and δ(10t) = 0.1δ(t)
91
An LVDT is a :
Answer
C. Passive transducer
92
An LVDT has a stroke length of ± 150 mm and a sensitivity of 40 mV/ mm. If the core is displaced 100 mm from the null position, and the signal conditioning circuit applies a gain of 2.5, determine the output voltage.
Answer
D. 10.0 V
93
Which type of battery cell is characterized by an irreversible chemical reaction, making it non-rechargeable?
Answer
C. Primary cells
94
A battery is formed by connecting 10 cells in series, each having an emf of 2 V and a capacity of 5 Ah. If two such series groups are connected in parallel, what will be the total battery rating?
Answer
D. 20 V, 10 Ah
95
According to ISI rules, the earth resistance of a domestic earthing system should not exceed :
Answer
C. 5 W
96
According to ISI standards, the maximum permissible load that can be connected in a power sub-circuit is :
Answer
D. 3000 watts
97
According to ISI standards, what is the minimum internal diameter of a pipe electrode used in a pipe electrode used in a pipe earthing system for domestic installations?
Answer
B. 38 mm
98
A hall measuring 10 ´ 8 m is illuminated by six 150-W lamps, each having a luminous efficiency of 75 lumens/W. If the coefficient of utilization is 0.6, what is the average illumination in the hall?
Answer
A. 506 lux
99
A 100 W lamp has a luminous intensity of 200 candela in all directions. Determine the total luminous flux emitted by the lamp
Answer
A. 800p lumen
100
Which type of lamp operates on the principle of gas discharge at low pressure, producing a characteristic yellow light with very high luminous efficiency?
Answer
B. Sodium vapour lamp
Discussion
Ask a doubt or share a tip.
No comments yet — start the discussion.