KDRB Assistant Engineer (Electrical) PYQ Free Mock Test

Question 1

Who got ONV Literary Award for the year 2022

A

C. Radhakrishnan

B

T. Padmanabhan

C

M. Mukundan

D

K.R. Meera

Question 2

Which Article of the Indian Constitution relates to GST Council?

A

Article 239 AA

B

Article 312

C

Article 280

D

Article 279 A

Question 3

The book 'Waiting for Mahatma' is written by

A

R.K. Narayan

B

Ramchandra Guha

C

Mulk Raj Anand

D

Gopalkrishna Gandhi

Question 4

Where is the World Economic Forum Annual Meeting held?

A

New York

B

Geneva

C

Davos

D

Hague

Question 5

Operation Ganga is associated with

A

Conservation and Rejuvenation of River Ganga

B

Evacuation of Indians from Ukraine

C

Campaign for reducing fuel consumption

D

Evacuation of Indians from Sri Lanka

Question 6

Azad Hind Fauj is organized by:

A

Chittaranjan Das

B

Sri Aurobindo

C

Bhagat Singh

D

Subhash Chandra Bose

Question 7

Which day is celebrated as National Voter's Day?

A

January 25

B

November 26

C

January 26

D

November 25

Question 8

Dostarlimab medicine is related to which disease?

A

AIDS

B

Asthma

C

Cancer

D

Alzheimer's

Question 9

Who is known as 'the Tendulkar of Women's Cricket'?

A

Ellyse Perry

B

Jhulan Goswami

C

Sana Mir

D

Mithali Raj

Question 10

Which Country Won the Thomas Cup 2022?

A

Indonesia

B

India

C

Australia

D

Germany

Question 11

A series RLC circuit has R = 2000, L= 50 mH and C = 0.60 F and a peak voltage of 40 Vat a frequency of 100 Hz. What is the rms value of the current in the circuit?

A

20 mA

B

14.14 A

C

19.5 mA

D

14.14 mA

Question 12

For the circuit given, find the reactive power:

A

119.998 VAr

B

119.365 VAr

C

169.256 VAr

D

119.998 W

Question 13

A resistor of 10Ω, inductance 0.3 H and capacitance of 100 µF are connected across 230 V, 50 Hz mains in series. Calculate the power factor :

A

Zero

B

0.158 lag

C

0.158 lead

D

Unity

Question 14

The value of ripple factor for a full wave rectifier is:

A

√3

B

1.21

C

√2

D

0.482

Question 15

Controlling torque in indicating instruments is commonly achieved by:

A

Fluid friction

B

Eddy currents

C

Air friction

D

Springs

Question 16

A coil in wound uniformly with 300 turns over a steel ring of relative permeability 900 having a mean circumference of 40 cm and a cross sectional area of 5 cm3. If the coil has a resistance of 100 Ωand is connected to 250 V dc supply, calculate the field strength:

A

1875 AT/m

B

750 AT/m

C

1500 AT/m

D

900 AT/m

Question 17

A coil of 1000 turns is linking a flux of 0.01 Wb. The flux is reversed in an interval of 0.1 sec. Calculate the average e.m.f. induced in the coil:

A

150 V

B

300 V

C

200 V

D

220 V

Question 18

A conductor of length 150 cm moves at an angle of 30° to a uniform magnetic field of flus density 2 T with a velocity of 100 m/sec. Calculate the e.m.f. induced in it:

A

75 V

B

150 V

C

37.5 V

D

50 V

Question 19

Determine the form factor of the output voltage wave of a half wave rectified:

A

1.11

B

√2

C

√3

D

1.57

Question 20

A 240 V, 50 Hz, AC supply is applied a coil of 0.08 H inductance and 4Ω resistance connected in series with a capacitor of 8 µF. Calculate the Q-factor of the circuit at resonant frequency.

A

25

B

50

C

75

D

100

Question 21

A parallel resonance network consisting of a resistor of 50 Ω, a capacitor of 100 µF and an inductor of 300 mH is connected across a sinusoidal supply voltage which has a constant output of 100 volts at all frequencies. Calculate the resonant frequency.

A

50 Hz

B

60 Hz

C

10.06 Hz

D

29.06 Hz

Question 22

A 12 pF capacitor is connected to a 50 V battery. How much electrostatic energy is stored in the capacitor?

A

25×10-4J

B

15x10-12J

C

15x10-4J

D

3.5x10-4J

Question 23

A 40 kVA 3300/240 V, 50 Hz, 1-phase transformer has 660 turns on the primary. Determine the number of turns on the secondary.

A

42

B

24

C

48

D

9075

Question 24

Find the voltage drop across R2

A

18 V

B

12 V

C

6V

D

36 V

Question 25

Find the current I in the circuit given

A

4 mA

B

6 mA

C

12 mA

D

11 mA

Question 26

Find the equivalent resistance across the terminals A & B of the following electrical network.

A

5 Ω

B

23 Ω

C

10 Ω

D

None of these

Question 27

What is Thevenin's voltage for the given circuit with load RLoad?

A

24 V

B

18 V

C

15 V

D

12 V

Question 28

For the given network, find the value of Is, which reduces the voltage across the 4Ω resistor to zero. (Hint: Use Superposition theorem)

A

2 A

B

3.5 A

C

1.5 A

D

1.25 A

Question 29

The inverse Laplace transform of H (S)= (S+3) / (S2+2S+1) for t≥0 is

A

3te-t+e-t

B

3e-t

C

2te-t+e-t

D

4te-t+e-t

Question 30

Laplace transform of the function shown below is given by:

A

(1-e-2s) / s

B

(1-e-s) / 2s

C

2(1-e-s) /s

D

1-2e-2s / s

Question 31

The function f(t) satisfies the differential equation d2f/dt2+f=0 and the auxiliary conditions, f(0) = 0, df/dt(0) =4. The Laplace transform of f(t) is given by

A

2 / s+1

B

4 / s2+1

C

3 / s+1

D

2 / s4+1

Question 32

The star equivalent resistance of 3 resistors having each resistance = 5 Ω is

A

1.5 Ω

B

3 Ω

C

4.5 Ω

D

1.67 Ω

Question 33 Cancelled (PSC)

Given two mutually coupled coils have a total inductance of 1500 mH, the self-inductance of each coils if the coefficient of coupling is 0.2 is

Question deleted as per Kerala PSC final answer key. That deleted questions are not calculated right or wrong answer.

A

625 mH

B

550 mH

C

325 mH

D

255 mH

Question 34

A capacitor, used for power factor correction in a single phase circuit increases which of the following?

A

Line Current

B

Power Factor

C

Both Line Current and Power Factor

D

Neither Line Current nor Power Factor

Question 35

What is Norton's resistance for the given circuit with load RLoad?

A

30 Ω

B

13.75 Ω

C

11 Ω

D

7.5 Ω

Question 36

Which of the following tests must be performed on a transformer to determine its core losses?

A

Routine tests

B

SC test only

C

OC test only

D

Both OC and SC tests

Question 37

The efficiency of a transformer at full load 0.85 pf lag is 95%. Its efficiency at full load 0.85 pf lead will be

A

More than 95%

B

Less than 95%

C

95%

D

100%

Question 38

Two transformers of identical voltages but of different capacities are operating in parallel. For satisfactory load sharing

A

Impedances must be equal

B

Per-unit impedances must be equal

C

Per-unit impedances and X/R ratios must be equal

D

Impedances and X/R ratios must be equal

Question 39

A single-winding single phase motor has

A

Low starting torque

B

Zero starting torque

C

High starting torque

D

Starting torque equal to full load torque

Question 40

A single phase stator winding when excited with ac voltage produces

A

A single rotating field rotating at synchronous speed

B

Two rotating fields rotating in the same directions but at different speeds

C

Two rotating fields rotating at synchronous speed in opposite directions

D

Two rotating fields rotating in opposite directions but with different speeds

Question 41

What should be observed if a de shunt motor is started with an open-circuited field?

A

The motor does not pick up speed but draws a large current

B

The motor does not pick up speed but draws only a small current

C

The motor picks up fast and acquires full speed while drawing large current

D

The motor picks up fast and acquires full speed while drawing small current

Question 42

A DC generator will have maximum efficiency when

A

Eddy current losses = Stray losses

B

Hysteresis losses = Eddy current losses

C

Copper loss = 0

D

Variable Losses Constant Losses

Question 43

The speed of a DC shunt motor can be increased by

A

Increasing the resistance in the armature circuit

B

Decreasing the resistance in the armature circuit

C

Increasing the resistance in the field circuit

D

Decreasing the resistance in the field circuit

Question 44

DC shunt motors are started with a starter

A

To restrict the armature current as the back emf is zero while starting

B

To restrict the field current as the back emf is zero while starting

C

These motors have high starting torque

D

To provide residual magnetism required for startup

Question 45

In a DC machine, which of the following speed control methods is least preferred?

A

Voltage Control method

B

Field Control method

C

Armature Control method

D

Ward-Leonard System

Question 46

Which of these features can be used to identify a DC series motor?

A

A motor with low starting torque

B

A motor with thick field windings

C

A motor which can be started easily without any load

D

A motor with constant speed

Question 47

Which of the following motors is used for a 20 HP hoist motor?

A

Single phase induction motors

B

DC shunt motors

C

PMDC motors

D

Wound field DC motors

Question 48

A 3-phase 440 V, 50 Hz induction motor has 3% slip. The frequency of rotor current will be

A

1.5 Hz

B

50 Hz

C

25 Hz

D

5 Hz

Question 49

In a three-phase induction motor, the number of poles in the rotor winding is always

A

Zero

B

More than the number of poles in the stator

C

Equal to the number of poles in the stator

D

Less than the number of poles in the stator

Question 50

A three-phase, four-pole, 50 Hz induction motor rotates at a full-load speed of 1470 rpm. The EMF measured between the slip-ring terminals when the rotor is not rotating is 200 V. The rotor windings are star connected and have resistance and stand-still reactance per phase of 0.1 Ω and 1.0 Ω respectively. Then the rotor current at full load is

A

25 A

B

11.2 A

C

15.43 A

D

22.5 A

Question 51

A 3-phase induction motor is running at 3% slip. If the input to rotor is 1000 W, then mechanical power developed by the motor in

A

970 W

B

30 W

C

500 W

D

300 W

Question 52

For a large range of speed changes, which of the following speed control techniques is used in squirrel cage induction motors?

A

Cascade Connection

B

Rheostatic Control

C

Pole changing method

D

Frequency Control

Question 53 Cancelled (PSC)

Which relay is found in a distribution transformer?

Question deleted as per Kerala PSC final answer key. That deleted questions are not calculated right or wrong answer.

A

Polarized Relay

B

Buchholz Relay

C

High-Voltage Relay

D

Small Signal Relay

Question 54

A vessel with silica gel to prevent the moist air entering into the tank in a transformer is called

A

Breather

B

Conservator

C

Buchholz Relay

D

Vent

Question 55

A single phase 800 V/100 V, 50 Hz transformer has a maximum core flux density of 1.294 T and an effective cross sectional area of 60 cm². Calculate the number of turns on the secondary windings.

A

100 turns

B

800 turns

C

464 turns

D

58 turns

Question 56 Cancelled (PSC)

For a uniformly distributed winding of an alternator with a phase spread of 𝛽 degrees, the distribution factor is ------- (Assume m=1)

Question deleted as per Kerala PSC final answer key. That deleted questions are not calculated right or wrong answer.

A

sin 𝛽/𝛽

B

2sin (𝛽/2)/𝛽

C

sin (𝛽/2)/𝛽

D

sin (𝛽/2)/2𝛽

Question 57

Two identical loss-less series motors connected in series across a dc supply voltage, run at speeds of N1, and N2, then ratio of their output powers will be

A

N12 : N22

B

1 : 1

C

N1 : N2

D

N2 : N1

Question 58

Slip test is performed to determine

A

Slip

B

Positive and negative sequence reactances

C

Sub Transient reactance

D

Direct and quadrature axis reactances

Question 59

Which of the following motors running under the specified conditions will have a leading power factor?

A

Double-cage induction motor at load

B

Over excited synchronous motor

C

Under excited synchronous motor

D

Slip ring induction motor at no load

Question 60

A circular iron core has an air-gap cut in it and is excited by passing direct current through a coil wound on it. The magnetic energy stored in the air-gap and the iron core is

A

Inverse ratio of their reluctances

B

Equally divided among them

C

In direct ratio of their reluctances

D

Energy resides wholly in the iron core

Question 61 Cancelled (PSC)

The transfer function of the system described by d2y/dt2 + dy/dt = du/dt + 3u where u is the input and y is the output is

Question deleted as per Kerala PSC final answer key. That deleted questions are not calculated right or wrong answer.

A

(s+3) / (s²+2)

B

(s+1) / (s²+2)

C

s / (s²+2)

D

3s / (s²+2)

Question 62

Consider the following statements regarding time-domain analysis of a control system:

(i) Derivative control improves system's transient performance

(ii) Integral control does not improve system's steady state performance

(iii) Integral control can convert a second order system into a third order system.

Of these statements:

A

(i) and (ii) are correct

B

(i) and (iii) are correct

C

(ii) and (iii) are correct

D

(i), (ii) and (iii) are correct

Question 63

The characteristic equation of a feedback system is:

s3+Ks2 +5s+10=0

For the system to be critically stable, the value of K should be:

A

1

B

2

C

3

D

4

Question 64

The phase margin of a system with the open-loop transfer function:

G(s) II(s) = (1-s) / (1+s)(3+s) is

A

0°

B

63.4°

C

90°

D

infinity

Question 65

A linear discrete-time system has the characteristic equation,

z3 = 0.64 2 = 0

The system

A

in stable

B

is marginally stable

C

is unstable

D

stability cannot be assessed

Question 66

Identify the circuit show

A

Half wave rectifier

B

Full wave bridge rectifier

C

Center-tapped full wave rectifier

D

Buck Circuit

Question 67

DC average current of a centre tapped full wave rectifier is:

A

2Im/π

B

Im/π

C

Im/2π

D

√2Im/π

Question 68

Which of these is incorrect for an operational amplifier?

A

It has a high voltage gain

B

It is a direct coupled amplifier

C

It was originally designed to perform mathematical operations

D

It is only useful for amplifying AC signals

Question 69

In an ideal op-amp, which is not true?

A

Slew rate is infinite

B

CMRR is zero

C

Input resistance is infinite

D

Open loop voltage gain is infinite

Question 70

In a BJT, if the collector-base junction is forward-biased and the base-emitter junction is forward-biased, which region is the BJT operating in?

A

Saturation region

B

Active region

C

Cutoff region

D

Reverse active region

Question 71

For common emitter configuration, which of the following is the correct relation?

A

Ic < IE

B

Ic = 𝛽 IB

C

Ic = IE

D

Ic = ɑIE

Question 72

What is the circuit in the given diagram called?

A

Half wave rectifier

B

Full wave rectifier

C

Clipper

D

Clamper

Question 73

What are the basic gates in CMOS logic family?

A

AND and OR

B

NAND and NOR

C

AND and NOR

D

NAND and OR

Question 74

What will be the frequency of the output from a JK flip-flop, when J = 1, K = 1, and a clock with pulse waveform is given?

A

Twice the frequency of clock input

B

Independent of the frequency of clock input

C

Half the frequency of clock input

D

Equal to the frequency of clock input

Question 75

Which of the following codes is a sequential code?

A

8421 code

B

2421 code

C

5421 code

D

2441 code

Question 76

Which of these pins will allow to activate and deactivate a multiplexer?

A

Preset pin

B

Logic pin

C

Enable pin

D

Selection pin

Question 77

The decimal equivalent of the octal number (645)8 is:

A

(450)10

B

(451)10

C

(501)10

D

(421)10

Question 78

Ripple counters are also called

A

SSI counters

B

Asynchronous counters

C

Synchronous counters

D

VLSI counters

Question 79 Cancelled (PSC)

Which of the following plays an important role in improving the device performance of MOSFET?

Question deleted as per Kerala PSC final answer key. That deleted questions are not calculated right or wrong answer.

A

Threshold voltage

B

Dielectric constant

C

Power supply voltage

D

Gate to drain voltage

Question 80

With a 200 kHz clock frequency, eight bits can be serially entered into a shift register in :

A

4 μs

B

40 μs

C

400 μs

D

4 ms

Question 81

Resistive switching is normally employed in

A

All circuit breakers

B

Bulk oil breakers

C

Minimum oil breakers

D

Air blast circuit breakers

Question 82

In case of a 3 phase short circuit in a system, the power fed into the system is:

A

mostly reactive

B

mostly active

C

active and reactive equally

D

reactive only

Question 83

Corona losses are minimized:

A

by reducing conductor size

B

by using smooth conductors

C

providing sharp points in line conductors

D

reducing current density in conductors

Question 84

The relay which is most sensitive to power swings (mal-operation) is:

A

mho relay

B

reactance relay

C

impedance relay

D

all relays:

Question 85

The capacitor switching is easily done with:

A

vacuum CB

B

M.O. circuit breaker

C

SF6 circuit breaker

D

air blast CB

Question 86

Which of the following power semiconductor devices is bidirectional?

A

Thyristor

B

Diac

C

BJT

D

IGBT

Question 87

Which of the following power semiconductor devices is a pulse triggered device?

A

BJT

B

MOSFET

C

IGBT

D

Thyristor

Question 88

Which one of the following triggering methods of an SCR is destructive?

A

Forward voltage triggering

B

Temperature triggering

C

Light triggering

D

Gate current triggering

Question 89 Cancelled (PSC)

For a three phase fully controlled bridge converter with R load, for what firing angle (alfa) the load current becomes discontinuous?

Question deleted as per Kerala PSC final answer key. That deleted questions are not calculated right or wrong answer.

A

ɑ

B

10

C

30

D

60

Question 90

For a three phase 50 Hz full converter, what is the ripple frequency in the output voltage?

A

50 Hz

B

100 Hz

C

300 Hz

D

150 Hz

Question 91

Devimahatmya, otherwise known as Durgasaptasati belongs to :

A

Bhagavatapurana

B

Brahmavaivartapurana

C

Padmapurana

D

Markandeyapurana

Question 92

In which philosophy, who asserts that the 'Absolute' can be realized through knowledge alone; karma and upasana are subsidiary.

A

Advaita Vedanta Philosophy, Sankara

B

Dvaita Vedanta Philosophy, Maddhva

C

Visistadvaita Vedanta Philosophy, Ramanuja

D

Suddhadvaita Vedanta Philosophy, Vallabha

Question 93

Which one of the following is the only famous War Festival of Kerala?

A

Padayani

B

Kappally Kumbham Thira

C

Chittur Konganpada

D

Kalpathy Rathotsavam

Question 94

Who is the present President of Cochin Devaswam Board?

A

Sri V.K. Ayyappan

B

Sri V. Nandakumar

C

Dr. V.K. Vijayan

D

Sri Chengara Surendran

Question 95

The Sukshma Sarira concept related to the pratistha (idol) is based on:

A

Thriguna concept of Sankhyasastra

B

Epistemology of Mimamsasastra

C

Nine fold forms of devotion

D

Aadhara Chakras mentioned in yogic literature

Question 96

Randumoorthi temple was established by:

A

Suresvaracharya

B

Padmapadacharya

C

Bilvamangalaswamikal

D

Hastamalakacharya

Question 97

Prajnanam Brahma' (Consciousness is The Absolute) is a Mahavakya which is occur in :

A

Mandukyopanisad

B

Brhadaranyakopanisad

C

Aitareyopanisad

D

Chandogyopanisad

Question 98

Who is the author of Tantrapaddhati?

A

Bhavatrata

B

Isanasivaguru

C

Vilvamangala

D

Parameswara

Question 99

Who was the Maharajah of Travancore signed the historic Temple Entry Proclamation on November 12, 1936?

A

Marthandavarma

B

Sthanu Ravi Varman

C

Bhaskara Ravi Varman II

D

Chithira Thirunal Balarama Varma

Question 100

Chandanakavu Saraswati Temple is located at:

A

Thirunavaya, Malappuram

B

Paravur, Ernakulam

C

Panachikkadu, Kottayam

D

Elavur, Ernakulam

105/2022 - Assistant Engineer (Electrical) - Guruvayur Devaswom