Official Paper

RRB JE CBT 2 (Electrical Engineering) ReExam Official Paper (Held On: 04 Jun, 2025) (Previous Year Paper)

150 questions · 120 minutes · with answers · free

Attempt as Timed Mock Test

General Abilities (50 questions)

1

Which of the following is an example of a chemical change?

  1. ((a))

    Dissolution of sugar in water

  2. ((b))

    Curdling of milk

  3. ((c))

    Freezing of water

  4. ((d))

    Tearing of paper

Show Answer
Answer: ((a))

Dissolution of sugar in water

2

If the area of contact increases while keeping the thrust constant, the pressure will __________.

  1. ((a))

    increase

  2. ((b))

    remain the same

  3. ((c))

    first increase, then decrease

  4. ((d))

    decrease

Show Answer
Answer: ((a))

increase

3

What happens when you use the 'Sort A to Z' option on a column containing text? 

  1. ((a))

    The text remains unchanged.

  2. ((b))

    The text is sorted alphabetically from A to Z.

  3. ((c))

    The text is sorted from Z to A. 

  4. ((d))

    The text is converted into numbers.

Show Answer
Answer: ((a))

The text remains unchanged.

4

The method of storage of nuclear wastes is to be done in _______.

  1. ((a))

    bottles

  2. ((b))

    dustbins

  3. ((c))

    open containers

  4. ((d))

    shielded containers

Show Answer
Answer: ((a))

bottles

5

When were the 38th National Games held in Uttarakhand?

  1. ((a))

    January 15 - 30, 2025

  2. ((b))

    January 28 - February 14, 2025

  3. ((c))

    February 10 - 25, 2025

  4. ((d))

    February 1 - 20, 2025

Show Answer
Answer: ((a))

January 15 - 30, 2025

6

In December 2024, Jasprit Bumrah became the fastest Indian bowler to reach 200 Test wickets during which of the following series/tournament? 

  1. ((a))

    Border-Gavaskar Trophy

  2. ((b))

    India vs England Test Series

  3. ((c))

    Asia Cup

  4. ((d))

    India vs New Zealand Test Series

Show Answer
Answer: ((a))

Border-Gavaskar Trophy

7

The Railways Employment of Members of the Armed Forces Act was passed in which of the following years?

  1. ((a))

    1951

  2. ((b))

    1962

  3. ((c))

    1965

  4. ((d))

    1957

Show Answer
Answer: ((a))

1951

8

Where is the magnetic field strength maximum around a magnet?

  1. ((a))

    Equidistant from the poles 

  2. ((b))

    At the poles of the magnet

  3. ((c))

    At infinity

  4. ((d))

    At the centre of the magnet

Show Answer
Answer: ((a))

Equidistant from the poles 

9

In an experiment, 25 g of reactant A reacts with 35 g of reactant B to form 50 g of product C and some amount of product D. What is the mass of product D?

  1. ((a))

    35 g

  2. ((b))

    25 g

  3. ((c))

    60 g

  4. ((d))

    10 g

Show Answer
Answer: ((a))

35 g

10

Which of the following is a zero waste procedure?

  1. ((a))

    Pest management

  2. ((b))

    Organic farming

  3. ((c))

    Integrated organic farming

  4. ((d))

    Inorganic farming

Show Answer
Answer: ((a))

Pest management

11

The greenhouse gas that is known to contribute the least amount to global warming is ___________.

  1. ((a))

    carbon dioxide

  2. ((b))

    methane

  3. ((c))

    CFCs

  4. ((d))

    nitrous oxide

Show Answer
Answer: ((a))

carbon dioxide

12

Two objects of masses 80 kg and 250 kg are placed 200 m apart. What is the gravitational force between them? (G = 6.7 × 10-11 N.m2/kg2)

  1. ((a))

    6.35 × 10-11 N

  2. ((b))

    5.75 × 10-11 N

  3. ((c))

    4.50 × 10-11 N

  4. ((d))

    3.35 × 10-11 N

Show Answer
Answer: ((a))

6.35 × 10-11 N

13

Which of the following is a string instrument?

  1. ((a))

    Tabla

  2. ((b))

    Sitar

  3. ((c))

    Flute

  4. ((d))

    Shehnai 

Show Answer
Answer: ((a))

Tabla

14

The speed of a wave is given by which of the following formulas?

  1. ((a))

    Speed = Time × Frequency

  2. ((b))

    Speed = Frequency × Amplitude

  3. ((c))

    Speed = Amplitude × Wavelength

  4. ((d))

    Speed = Frequency × Wavelength 

Show Answer
Answer: ((a))

Speed = Time × Frequency

15

The loss of forests, which is remarkably seen in the tropical areas of India, is around __________. 

  1. ((a))

    40%

  2. ((b))

    30%

  3. ((c))

    20%

  4. ((d))

    10%

Show Answer
Answer: ((a))

40%

16

As per Article 78, it is the duty of the Prime Minister to communicate all decisions of the Council of Ministers to whom? 

  1. ((a))

    Chief Justice of India

  2. ((b))

    Speaker of Lok Sabha

  3. ((c))

    President

  4. ((d))

    Vice President

Show Answer
Answer: ((a))

Chief Justice of India

17

What is the purpose of the 'BCC' field in an email? 

  1. ((a))

    It hides recipients from each other. 

  2. ((b))

    It deletes an email after it is read. 

  3. ((c))

    It allows recipients to see each others' addresses.

  4. ((d))

    It marks an email as urgent.

Show Answer
Answer: ((a))

It hides recipients from each other. 

18

_____ is the most efficient method used for the disposal of hospital-generated waste.

  1. ((a))

    Sanitary landfills

  2. ((b))

    Incinerator

  3. ((c))

    Furnace

  4. ((d))

    Open dumps

Show Answer
Answer: ((a))

Sanitary landfills

19

Under the Delhi Sultanate what was the name of the state laws that grew under the monarchy, even if they violated the Shari’at? 

  1. ((a))

    Farman

  2. ((b))

    Iqta

  3. ((c))

    Zawabit

  4. ((d))

    Fatwas

Show Answer
Answer: ((a))

Farman

20

Which statement correctly explains why liquids can flow?

  1. ((a))

    Liquids have no intermolecular forces.

  2. ((b))

    Liquids have loosely packed molecules that slide past each other. 

  3. ((c))

    Liquids do not have kinetic energy. 

  4. ((d))

    Liquid molecules move randomly without any restriction.

Show Answer
Answer: ((a))

Liquids have no intermolecular forces.

21

If three resistors of 15 Ω, 35 Ω and 50 Ω are connected in series to a 25-V battery, what is the current flowing in the circuit?

  1. ((a))

    4 A

  2. ((b))

    1.5 A

  3. ((c))

    0.25 A

  4. ((d))

    2.88 A

Show Answer
Answer: ((a))

4 A

22

What is the function of the Linux Shell?

  1. ((a))

    To directly manage hardware resources

  2. ((b))

    To execute user commands and act as an interface between the user and the kernel

  3. ((c))

    To store user data

  4. ((d))

    To create and delete partitions

Show Answer
Answer: ((a))

To directly manage hardware resources

23

Which of the following economic estimators provided estimates of India’s national and per capita income during the colonial period? 

  1. ((a))

    Adam Smith

  2. ((b))

    John Maynard Keynes

  3. ((c))

    VKRV Rao

  4. ((d))

    Karl Marx

Show Answer
Answer: ((a))

Adam Smith

24

Which of the following is NOT an example of an agrochemical?

  1. ((a))

    Pesticides

  2. ((b))

    Fungicides

  3. ((c))

    Herbicides

  4. ((d))

    Biogas

Show Answer
Answer: ((a))

Pesticides

25

What is the typical range of a Local Area Network (LAN)?

  1. ((a))

    Up to 10 km

  2. ((b))

    Up to 5 km

  3. ((c))

    Up to 1 km

  4. ((d))

    More than 50 km

Show Answer
Answer: ((a))

Up to 10 km

26

According to the Tendulkar methodology, what was the estimated national poverty line for rural areas in 2011-12?

  1. ((a))

    ₹816 per month

  2. ((b))

    ₹1,200 per month

  3. ((c))

    ₹1,000 per month

  4. ((d))

    ₹512 per month

Show Answer
Answer: ((a))

₹816 per month

27

What are the sand dunes commonly found in the Indian Desert called?

  1. ((a))

    Barchans

  2. ((b))

    Loess

  3. ((c))

    Moraines

  4. ((d))

    Cirques

Show Answer
Answer: ((a))

Barchans

28

If the mass of an object is 74.5 kg, what is its approximate weight on Earth? (Take g = 9.8 m/s2)

  1. ((a))

    730 N

  2. ((b))

    447 N

  3. ((c))

    7.6 N

  4. ((d))

    74.5 N

Show Answer
Answer: ((a))

730 N

29

The Montreal Protocol came into force in the year ________. 

  1. ((a))

    1986

  2. ((b))

    1989

  3. ((c))

    1990

  4. ((d))

    1992

Show Answer
Answer: ((a))

1986

30

Which property of solids allows them to be compressed the least compared to liquids and gases? 

  1. ((a))

    High intermolecular spaces

  2. ((b))

    The ability to diffuse into other solids

  3. ((c))

    Strong intermolecular forces and close packing of particles

  4. ((d))

    High kinetic energy of particles

Show Answer
Answer: ((a))

High intermolecular spaces

31

Which of the following best describes a heterogeneous mixture? 

  1. ((a))

    It has a uniform composition. 

  2. ((b))

    The components cannot be separated.

  3. ((c))

    The composition varies throughout the mixture.

  4. ((d))

    It contains only one phase

Show Answer
Answer: ((a))

It has a uniform composition. 

32

A student calculates the formula unit mass of calcium fluoride (CaF2). If the atomic masses of Ca and F are 40 u and 19 u, respectively, what is the correct formula unit mass?

  1. ((a))

    97 u

  2. ((b))

    78 u

  3. ((c))

    100 u

  4. ((d))

    59 u

Show Answer
Answer: ((a))

97 u

33

The area termed as the ozone hole is known to mainly develop over ______.

  1. ((a))

    India

  2. ((b))

    Africa

  3. ((c))

    Antartica

  4. ((d))

    America

Show Answer
Answer: ((a))

India

34

Who among the following is NOT appointed by the President of India? 

  1. ((a))

    Governors of States

  2. ((b))

    Vice President

  3. ((c))

    Chief Election Commissioner

  4. ((d))

    Comptroller and Auditor General 

Show Answer
Answer: ((a))

Governors of States

35

Which dynasty was overthrown by Chandragupta Maurya to establish the Mauryan Empire?

  1. ((a))

    Gupta Dynasty

  2. ((b))

    Kushan Dynasty

  3. ((c))

    Shunga Dynasty

  4. ((d))

    Nanda Dynasty

Show Answer
Answer: ((a))

Gupta Dynasty

36

Which of the following is NOT an example of system software?

  1. ((a))

    macOS

  2. ((b))

    Linux

  3. ((c))

    Microsoft Word

  4. ((d))

    Windows 10

Show Answer
Answer: ((a))

macOS

37

Which of the following metals is placed above aluminium and zinc in the reactivity series?

  1. ((a))

    Magnesium

  2. ((b))

    Iron

  3. ((c))

    Copper

  4. ((d))

    Carbon

Show Answer
Answer: ((a))

Magnesium

38

Who among the following won the gold medal in the women's high jump event at the National Games in February 2025?

  1. ((a))

    Vithya Ramraj 

  2. ((b))

    Pooja Singh

  3. ((c))

    Abhinaya Shetty

  4. ((d))

    Swapna Barman

Show Answer
Answer: ((a))

Vithya Ramraj 

39

Which of the following is an effective way to prevent rancidity in packaged food?

  1. ((a))

    Adding antioxidants

  2. ((b))

    Increasing moisture content 

  3. ((c))

    Keeping it in direct sunlight

  4. ((d))

    Storing in a warm place

Show Answer
Answer: ((a))

Adding antioxidants

40

The Punjab Plain is formed by which river system?

  1. ((a))

    Indus and its tributaries

  2. ((b))

    Narmada and its tributaries

  3. ((c))

    Ganga and its tributaries

  4. ((d))

    Brahmaputra and its tributaries

Show Answer
Answer: ((a))

Indus and its tributaries

41

An object is placed 25 cm in front of a convex lens with a focal length of 15 cm. What is the magnification produced by the lens?

  1. ((a))

    M = −2.5

  2. ((b))

    M = 1.5 

  3. ((c))

    M = 2.5

  4. ((d))

    M = −1.5

Show Answer
Answer: ((a))

M = −2.5

42

The effect of particulate matter which is a common air pollutant is maximally seen on the _______.

  1. ((a))

    intestines

  2. ((b))

    kidneys

  3. ((c))

    lungs

  4. ((d))

    liver

Show Answer
Answer: ((a))

intestines

43

The Indian Desert lies towards the western margins of which mountain range?

  1. ((a))

    Western Ghats

  2. ((b))

    Satpura Hills

  3. ((c))

    Vindhya Hills

  4. ((d))

    Aravali Hills

Show Answer
Answer: ((a))

Western Ghats

44

What is the primary goal of application security?

  1. ((a))

    To reduce the size of application files

  2. ((b))

     To enhance the graphical user interface of applications

  3. ((c))

    To protect applications from security threats by identifying and fixing vulnerabilities

  4. ((d))

    To increase the execution speed of applications

Show Answer
Answer: ((a))

To reduce the size of application files

45

Which of the following is an example of database management software?

  1. ((a))

    MS Paint

  2. ((b))

    Notepad

  3. ((c))

    PowerPoint

  4. ((d))

    Microsoft Access

Show Answer
Answer: ((a))

MS Paint

46

Which of the following is NOT a file management task? 

  1. ((a))

    Creating files

  2. ((b))

    Browsing the internet

  3. ((c))

    Renaming files

  4. ((d))

    Deleting files

Show Answer
Answer: ((a))

Creating files

47

Which mouse pointer appears when adjusting column width / cell width in a table?

  1. ((a))

    ↔ (Horizontal double-headed arrow) 

  2. ((b))

    ↕ (Vertical double-headed arrow)

  3. ((c))

    I-beam (Text cursor)

  4. ((d))

    Hand cursor

Show Answer
Answer: ((a))

↔ (Horizontal double-headed arrow) 

48

The melting of snow and ice caps from the polar regions is responsible for ________.

  1. ((a))

    condensation

  2. ((b))

    the rise in sea levels

  3. ((c))

    the decline in sea levels

  4. ((d))

    rainfall 

Show Answer
Answer: ((a))

condensation

49

In September 2024, which of the following Indian institutions was designated as the Thematic Hub for Quantum Computing under the National Quantum Mission?

  1. ((a))

    Indian Institute of Technology Madras

  2. ((b))

    Indian Institute of Technology Kanpur

  3. ((c))

    Indian Institute of Technology Gandhinagar

  4. ((d))

    Indian Institute of Science Bengaluru

Show Answer
Answer: ((a))

Indian Institute of Technology Madras

50

Which of the following is an example of a WAN?

  1. ((a))

    A Bluetooth connection between a phone and a laptop

  2. ((b))

    A home Wi-Fi network

  3. ((c))

    The internet

  4. ((d))

    A university campus network

Show Answer
Answer: ((a))

A Bluetooth connection between a phone and a laptop

Technical Abilities (100 questions)

51

The load on a power plant on a typical day is as given in the following table.

Time0-66-99-1818-2222-24
Load (MW)2408010025
<br>

Find the load factor of the plant.

  1. ((a))

    60%

  2. ((b))

    40%

  3. ((c))

    50%

  4. ((d))

    80%

Show Answer
Answer: ((a))

60%

52

For a P-N junction diode, thermal equilibrium occurs when _________.

  1. ((a))

    force produced by the electric field is always zero

  2. ((b))

    force produced by the electric field and the 'force' produced by the density gradient exactly balance

  3. ((c))

    force produced by the electric field is greater than the 'force' produced by the density gradient

  4. ((d))

    force produced by the electric field is less than the 'force' produced by the density gradient 

Show Answer
Answer: ((a))

force produced by the electric field is always zero

53

The unit of magnetising force is:

  1. ((a))

    weber/metre2

  2. ((b))

    joule/weber

  3. ((c))

    ampere/metre

  4. ((d))

    henry/metre

Show Answer
Answer: ((a))

weber/metre2

54

A 10-ohm resistor is connected across a 12-V battery. How much current flows through the resistor?

  1. ((a))

    0.8 A

  2. ((b))

    2.0 A

  3. ((c))

    120 A

  4. ((d))

    1.2 A

Show Answer
Answer: ((a))

0.8 A

55

In the right-hand rule, the thumb points in the direction of ______________.

  1. ((a))

    lines of flux

  2. ((b))

    current

  3. ((c))

    motion

  4. ((d))

    magnetic field

Show Answer
Answer: ((a))

lines of flux

56

What is the modified starter called when the holding coil circuit is made independent of the field circuit? 

  1. ((a))

    2-point starter

  2. ((b))

    3-point starter

  3. ((c))

    4-point starter

  4. ((d))

    5-point starter

Show Answer
Answer: ((a))

2-point starter

57

Calculate the ripple factor (in percentage) if the dc and ac voltmeter used to measure the output signal from a rectifier circuit gives the readings of 25 V dc and 1.5 V rms.

  1. ((a))

    17%

  2. ((b))

    34%

  3. ((c))

    25%

  4. ((d))

    6%

Show Answer
Answer: ((a))

17%

58

What is the primary mechanism of current conduction in a Bipolar Junction Transistor (BJT)? 

  1. ((a))

    Electromagnetic induction

  2. ((b))

    Majority carrier conduction 

  3. ((c))

    Minority carrier conduction

  4. ((d))

    Electrostatic induction

Show Answer
Answer: ((a))

Electromagnetic induction

59

The real part of admittance in phasor form is called _______ and the imaginary part is called _________.

  1. ((a))

    impedance; reactance

  2. ((b))

    reactance; conductance

  3. ((c))

    resistance; reactance

  4. ((d))

    conductance; susceptance

Show Answer
Answer: ((a))

impedance; reactance

60

How does a servo motor control its shaft position?

  1. ((a))

    By adjusting the frequency of the AC supply

  2. ((b))

    By changing stator winding resistance

  3. ((c))

    By varying input voltage

  4. ((d))

    Using pulse-width modulation (PWM) signals 

Show Answer
Answer: ((a))

By adjusting the frequency of the AC supply

61

Applications of synchronous reluctance motors include:

I. Industrial compressors for improved energy efficiency.

II. Electric trains for high starting torque capabilities.

III. Solar-powered water pumps for reliability.

IV. Consumer drones for compact size.

  1. ((a))

    Statement II and III only correct.

  2. ((b))

    Statement II and IV only correct. 

  3. ((c))

    Statement I and IV only correct. 

  4. ((d))

    Statement I and III only correct.

Show Answer
Answer: ((a))

Statement II and III only correct.

62

What is the primary purpose of estimation in electrical installations? 

  1. ((a))

    To ensure compliance with aesthetic design standards

  2. ((b))

    To focus solely on the operation and maintenance of electrical systems

  3. ((c))

    To replace the need for protective devices in electrical systems

  4. ((d))

    To predict the cost, materials and time required for completing an electrical project 

Show Answer
Answer: ((a))

To ensure compliance with aesthetic design standards

63

Which of the following factors most significantly affects the efficiency of a Fresnel reflector in a solar concentrator system?

  1. ((a))

    The number of mirror strips and their alignment accuracy

  2. ((b))

    The temperature of the environment 

  3. ((c))

    The colour of the reflector material

  4. ((d))

    The wavelength of incident light

Show Answer
Answer: ((a))

The number of mirror strips and their alignment accuracy

64

The unit of reluctance is _______.

  1. ((a))

    Weber

  2. ((b))

    Ampere-turn/Weber 

  3. ((c))

    Henry

  4. ((d))

    Ampere/Weber

Show Answer
Answer: ((a))

Weber

65

The back-EMF waveform of a BLDC motor is typically ______.

  1. ((a))

    Square

  2. ((b))

    Trapezoidal 

  3. ((c))

    Triangular

  4. ((d))

    Sinusoidal

Show Answer
Answer: ((a))

Square

66

Why is WRIG preferred over Squirrel Cage Induction Generator (SCIG) in some wind turbines?

  1. ((a))

    WRIG does not require maintenance due to the absence of slip rings

  2. ((b))

    WRIG allows external rotor resistance control, enabling better efficiency and power factor control

  3. ((c))

    WRIG works only with constant-speed wind turbines

  4. ((d))

    WRIG has no moving parts, making it more durable

Show Answer
Answer: ((a))

WRIG does not require maintenance due to the absence of slip rings

67

Which of the following statements describe applications of three-phase squirrel cage induction motors?

I. Driving escalators and elevators.

II. Powering household refrigerators.

III. Operating centrifugal pumps in industrial plants.

IV. Used in electric vehicles for propulsion.

  1. ((a))

    II, and IV only correct

  2. ((b))

    I, II, and III only correct 

  3. ((c))

    I and III only correct

  4. ((d))

    I and IV only correct

Show Answer
Answer: ((a))

II, and IV only correct

68

In a transmission line with supports at different heights, the lowest point of the conductor is located:

  1. ((a))

    exactly at the midpoint of the span

  2. ((b))

    closer to the lower support 

  3. ((c))

    closer to the higher support

  4. ((d))

    at the higher support

Show Answer
Answer: ((a))

exactly at the midpoint of the span

69

Which system is responsible for delivering electricity from local transformers to endusers?

  1. ((a))

    Generation system

  2. ((b))

    Primary distribution system

  3. ((c))

    Transmission system

  4. ((d))

    Secondary distribution system

Show Answer
Answer: ((a))

Generation system

70

Which of the following is NOT an example of solid biomass?

  1. ((a))

    Natural gas

  2. ((b))

    Firewood

  3. ((c))

    Sugarcane bagasse

  4. ((d))

    Wood pellets

Show Answer
Answer: ((a))

Natural gas

71

Which of the following statements is/are correct?

Statement 1: A single large generating unit requires periodic maintenance, which may lead to a complete shutdown of power supply.

Statement 2: In a multi-unit system, maintenance can be scheduled without completely interrupting power generation.

  1. ((a))

    Only Statement 1

  2. ((b))

    Only Statement 2

  3. ((c))

    Neither Statement 1 nor Statement 2

  4. ((d))

    Both Statement 1 and Statement 2

Show Answer
Answer: ((a))

Only Statement 1

72

If R is the resistance of an R-L series circuit and reactive inductance is XL , then the power factor of a series R-L circuit is given by _______.

  1. ((a))

    cos⁡θ=XLZ\rm \cos \theta=\frac{X_L}{Z}

  2. ((b))

    x=−b±b2−4ac2ax = {-b \pm \sqrt{b^2-4ac} \over 2a}

    cos⁡θ=ZR\rm \cos \theta=\frac{Z}{R}

  3. ((c))

    cos⁡θ=RZ\rm \cos \theta=\frac{R}{Z}

  4. ((d))

    cos⁡θ=RXL\rm \cos \theta=\frac{R}{X_L}

Show Answer
Answer: ((a))

cos⁡θ=XLZ\rm \cos \theta=\frac{X_L}{Z}

73

If a straight long conductor is carrying current, the magnetic lines of force will be:

  1. ((a))

    only anticlockwise around the conductor

  2. ((b))

    only clockwise around the conductor

  3. ((c))

    concentric circles clockwise/anticlockwise around the conductor

  4. ((d))

    in straight line across the conductor

Show Answer
Answer: ((a))

only anticlockwise around the conductor

74

The material used in the armature core of a DC generator is typically: 

  1. ((a))

    silicon steel 

  2. ((b))

    copper

  3. ((c))

    aluminium

  4. ((d))

    plastic

Show Answer
Answer: ((a))

silicon steel 

75

Consider three doping concentration levels represented by i) n++, ii) p+ and iii) n. Relate the corresponding doping concentration with emitter, base and collector regions for a NPN transistor

  1. ((a))

    i. n++ corresponds to base, ii. p+ corresponds to collector and, iii. n for emitter

  2. ((b))

    i. n++ corresponds to emitter, ii. p+ corresponds to base and, iii. n for collector

  3. ((c))

    i. n++ corresponds to collector, ii. p+ corresponds to base and, iii. n for emitter

  4. ((d))

    i. n++ corresponds to base, ii. p+ corresponds to emitter and, iii. n for collector

Show Answer
Answer: ((a))

i. n++ corresponds to base, ii. p+ corresponds to collector and, iii. n for emitter

76

The EMF generated in a rotating coil within a uniform magnetic field is maximum when _________. 

  1. ((a))

    the coil is parallel to the magnetic field

  2. ((b))

    the rate of change of flux is minimum

  3. ((c))

    the current is maximum

  4. ((d))

    the coil is perpendicular to the magnetic field

Show Answer
Answer: ((a))

the coil is parallel to the magnetic field

77

When the armature and field of a DC motor are supplied with current, what does the armature experience?

  1. ((a))

    An unstable force that tries to halt rotation

  2. ((b))

    No force at all

  3. ((c))

    A force that resists rotation

  4. ((d))

    A force that tries to rotate it in an appropriate direction

Show Answer
Answer: ((a))

An unstable force that tries to halt rotation

78

A hydroelectric power plant has the following parameters:

Flow rate (Q) = 50 m³/s

Electrical power output (Pout) = 8 MW

Water density (ρ) = 1000 kg/m3

Acceleration due to gravity (g) = 10 m/s2

To achieve an overall efficiency of 80%, what should be the required net head (H)?

  1. ((a))

    19.50 m

  2. ((b))

    22.15 m

  3. ((c))

    18.75 m

  4. ((d))

    20 m

Show Answer
Answer: ((a))

19.50 m

79

A transmission line has a span length of 300 metres, and the conductor weight is 1 .2 N/m. If the tension in the conductor is 6000 N, what is the sag? 

  1. ((a))

    6 m

  2. ((b))

    2.25 m

  3. ((c))

    5 m

  4. ((d))

    1 m

Show Answer
Answer: ((a))

6 m

80

Assertion (A): Switched Reluctance Motors (SRMs) exhibit high torque ripple. Reason (R): SRMs operate based on constant and steady excitation of stator phases.

Which of the following is correct?

  1. ((a))

    A is true, but R is false.

  2. ((b))

    Both A and R are true, but R is not the correct explanation of A. 

  3. ((c))

    A is false, but R is true.

  4. ((d))

    Both A and R are true, and R is the correct explanation of A. 

Show Answer
Answer: ((a))

A is true, but R is false.

81

Which of the following statements regarding phase sequence is INCORRECT?

  1. ((a))

    An incorrect phase sequence can cause a motor to run in reverse.

  2. ((b))

    Phase sequence can be changed by interchanging two phases. 

  3. ((c))

    If two phases are interchanged, the phase sequence remains the same

  4. ((d))

    The phase sequence in a three-phase system determines the direction of motor rotation. 

Show Answer
Answer: ((a))

An incorrect phase sequence can cause a motor to run in reverse.

82

At the point of saturation in a DC series motor, the torque becomes proportional to:

  1. ((a))

    armature current only

  2. ((b))

    both armature current and field flux

  3. ((c))

    field flux only

  4. ((d))

    the square of the armature current 

Show Answer
Answer: ((a))

armature current only

83

What is the primary cause of the built-in potential at a p-n junction?

  1. ((a))

    Diffusion of electrons from n-type to p-type material, resulting in a potential barrier

  2. ((b))

    Drift of holes from p-type to n-type material, resulting in a potential barrier

  3. ((c))

    Difference in bandgap energy between p-type and n-type materials 

  4. ((d))

    Difference in electron affinity between p-type and n-type materials

Show Answer
Answer: ((a))

Diffusion of electrons from n-type to p-type material, resulting in a potential barrier

84

In a three-phase system, the active power (P) is given by which of the following formulas?

  1. ((a))

    √3 VLIL cos Φ

  2. ((b))

    VLIL

  3. ((c))

    3 VLIL cos Φ

  4. ((d))

    VLIL cos Φ

Show Answer
Answer: ((a))

√3 VLIL cos Φ

85

The important property of magnetic lines of force is that:

  1. ((a))

    magnetic lines of force intersect each other at infinity

  2. ((b))

    magnetic lines of force never flows in closed loop. 

  3. ((c))

    magnetic lines of force intersect within the magnet

  4. ((d))

    no two magnetic lines of force intersect each other

Show Answer
Answer: ((a))

magnetic lines of force intersect each other at infinity

86

What happens to the Fermi level in a p-n junction at equilibrium? 

  1. ((a))

    It rises in the p-side and falls in the n-side. 

  2. ((b))

    It remains constant throughout the junction

  3. ((c))

    It disappears at the junction. 

  4. ((d))

    It falls in the p-side and rises in the n-side. 

Show Answer
Answer: ((a))

It rises in the p-side and falls in the n-side. 

87

Two capacitors A and B are connected in series across a 200 V DC supply. The PD across A is 60 V. This PD is increased to 80 V when a 3 μF capacitor is connected in parallel with B. Calculate the capacitance of B. 

  1. ((a))

    7.8 µF

  2. ((b))

    3.5 µF

  3. ((c))

    5.4 µF

  4. ((d))

    2.7 µF

Show Answer
Answer: ((a))

7.8 µF

88

What is a key consideration when designing an electrical installation scheme for a factory?

  1. ((a))

    Providing adequate protection against overloads, short circuits, and earth faults

  2. ((b))

    Minimising the use of protective devices to reduce costs

  3. ((c))

    Focusing only on lighting and ventilation systems

  4. ((d))

    Ensuring the system is aesthetically pleasing

Show Answer
Answer: ((a))

Providing adequate protection against overloads, short circuits, and earth faults

89

Core losses in a transformer are proportional to:

  1. ((a))

    the square of the frequency

  2. ((b))

    the square of the stator current

  3. ((c))

    the square of the voltage

  4. ((d))

    the square of the load current

Show Answer
Answer: ((a))

the square of the frequency

90

Whenever a P-N junction diode is forward biased, the width of the space charge region _________ and the forward current __________ for rise in supply voltage.

  1. ((a))

    becomes zero; increases

  2. ((b))

    becomes zero; decreases

  3. ((c))

    decreases; increases 

  4. ((d))

    increases; decreases

Show Answer
Answer: ((a))

becomes zero; increases

91

What is the significance of the ideality factor (η) in the Shockley diode equation?

  1. ((a))

    It accounts for the reverse saturation current.

  2. ((b))

    It accounts for the non-ideal behaviour of the diode. 

  3. ((c))

    It accounts for the thermal energy of the electrons.

  4. ((d))

    It accounts for the recombination of electrons and holes in the depletion region.

Show Answer
Answer: ((a))

It accounts for the reverse saturation current.

92

What is the significance of the Quiescent point (Q-point) in a transistor amplifier circuit?

  1. ((a))

    It is the point where the transistor is cut off. 

  2. ((b))

    It represents the minimum current gain of the transistor. 

  3. ((c))

    It represents the maximum power output of the amplifier. 

  4. ((d))

    It is the operating point where the transistor operates without an input signal.

Show Answer
Answer: ((a))

It is the point where the transistor is cut off. 

93

If the reactive power of a three-phase system is 12 kVAR and the active power is 16 kW, then what is the apparent power?

  1. ((a))

    20 kVA

  2. ((b))

    28 kVA

  3. ((c))

    4 kVA

  4. ((d))

    10 kVA

Show Answer
Answer: ((a))

20 kVA

94

In a three-phase balanced system, if the phase voltage is represented as VA = 230 <0°, then the voltage for phase B will be _____.

  1. ((a))

    VB = 230∠90°

  2. ((b))

    VB = 230∠120°

  3. ((c))

    VB = 230∠-120°

  4. ((d))

    VB = 230∠100°

Show Answer
Answer: ((a))

VB = 230∠90°

95

In a DC series motor, at low or light load, why is the torque low?

  1. ((a))

    Due to the low armature current and low field flux

  2. ((b))

    Due to the saturation of the field cores

  3. ((c))

    Due to the high field flux

  4. ((d))

    Due to the high armature current

Show Answer
Answer: ((a))

Due to the low armature current and low field flux

96

Which of the following statements are correct for repulsion-induction motors?

I. They combine features of repulsion and induction motors.

II. The rotor has both commutator and squirrel-cage windings.

III. Speed decreases sharply with increasing load.

IV. They are used in applications requiring constant speed.

  1. ((a))

    Statement III and IV only correct 

  2. ((b))

    Statement I and IV only correct

  3. ((c))

    Statement I and II only correct

  4. ((d))

    Statement II and III only correct

Show Answer
Answer: ((a))

Statement III and IV only correct 

97

If the capacitance C in a parallel RLC circuit decreases, what happens to resonant frequency f0?

  1. ((a))

    Decreases

  2. ((b))

    Increases

  3. ((c))

    Remains constant

  4. ((d))

    Becomes zero

Show Answer
Answer: ((a))

Decreases

98

If wind speed doubles, the Wind Power Density increases by a factor of ________.

  1. ((a))

    6

  2. ((b))

    8

  3. ((c))

    4

  4. ((d))

    2

Show Answer
Answer: ((a))

6

99

In a parallel resistance (R) and capacitor (C) circuit, if resistance R increases, the phase angle ϕ __________. 

  1. ((a))

    increases 

  2. ((b))

    becomes zero

  3. ((c))

    remains the same

  4. ((d))

    decreases

Show Answer
Answer: ((a))

increases 

100

The parameters which can be obtained from output characteristics curves of common emitter BJT NPN transistor is/are:

  1. ((a))

    forward current amplification factor and input resistance of CE configuration

  2. ((b))

    input resistance of CE configuration only

  3. ((c))

    output resistance of CE configuration only

  4. ((d))

    forward current amplification factor and output resistance of CE configuration

Show Answer
Answer: ((a))

forward current amplification factor and input resistance of CE configuration

101

Which of the following statements is NOT correct regarding resonance in a series circuit?

  1. ((a))

    The voltage across the capacitor and inductor is equal and opposite

  2. ((b))

    The circuit behaves as a purely resistive circuit.

  3. ((c))

    The net reactance of the circuit is zero

  4. ((d))

    The phase angle of the circuit is 90° 

Show Answer
Answer: ((a))

The voltage across the capacitor and inductor is equal and opposite

102

In an SF6 (Sulphur Hexafluoride) circuit breaker, the fixed contact is:

  1. ((a))

    a spherical contact with an insulating shield

  2. ((b))

    a solid cylindrical contact with no additional fittings

  3. ((c))

    a flat plate contact with thermal insulation

  4. ((d))

    a hollow cylinder contact with an arc horn

Show Answer
Answer: ((a))

a spherical contact with an insulating shield

103

Why are wind turbine blades made of glass fibre reinforced polyester?

  1. ((a))

    To reduce cost

  2. ((b))

    To provide lightweight strength and durability

  3. ((c))

    To increase the efficiency of power transmission

  4. ((d))

    To make them heavier for stability

Show Answer
Answer: ((a))

To reduce cost

104

In a balanced beam type relay, what happens under normal working conditions?

  1. ((a))

    The current through the coil causes the beam to tilt downward.

  2. ((b))

    The beam oscillates between horizontal and tilted positions. 

  3. ((c))

    The spring compresses completely to maintain stability.

  4. ((d))

    The beam is held in a horizontal position by the spring. 

Show Answer
Answer: ((a))

The current through the coil causes the beam to tilt downward.

105

Assertion (A): Detent torque is present in permanent magnet stepper motors even when unpowered.

Reason (R): Detent torque arises from the interaction between the rotor magnets and stator teeth.

Which of the following option is correct?

  1. ((a))

    Both A and R are true, but R does not explain A. 

  2. ((b))

    Both A and R are false.

  3. ((c))

    A is false, but R is true.

  4. ((d))

    Both A and R are true, and R explains A. 

Show Answer
Answer: ((a))

Both A and R are true, but R does not explain A. 

106

What happens to the depletion layer in a P-N junction when it is reverse-biased?

  1. ((a))

    The depletion layer disappears.

  2. ((b))

    The depletion layer narrows.

  3. ((c))

    The depletion layer remains unchanged.

  4. ((d))

    The depletion layer widens.

Show Answer
Answer: ((a))

The depletion layer disappears.

107

Which of the following options is always true about the demand factor?

  1. ((a))

    It is always greater than 1.

  2. ((b))

    It is always equal to the utilisation factor.

  3. ((c))

    It is always less than or equal to 1.

  4. ((d))

    It is always equal to the diversity factor. 

Show Answer
Answer: ((a))

It is always greater than 1.

108

Laplace transform is applicable to ___________ signals.

  1. ((a))

    integral time

  2. ((b))

    continuous time domain

  3. ((c))

    non linear

  4. ((d))

    digital

Show Answer
Answer: ((a))

integral time

109

Determine the peak value of the output signal of the half wave rectifier or a series clipper realised using a single diode having forward voltage of 0.6 V, if the input applied the circuit is periodic sinusoidal signal of 10 V peak to peak voltage. 

  1. ((a))

    5 V

  2. ((b))

    9.4 V

  3. ((c))

    10 V

  4. ((d))

    4.4 V

Show Answer
Answer: ((a))

5 V

110

In which situation will an EMF be induced in a conductor, according to Faraday's Laws?

  1. ((a))

    When the temperature of the conductor increases

  2. ((b))

    When the conductor is stationary in a magnetic field

  3. ((c))

    When the magnetic field is constant

  4. ((d))

    When there is relative motion between a conductor and a magnetic field

Show Answer
Answer: ((a))

When the temperature of the conductor increases

111

A power plant has a rated capacity of 200 MW and operates for 10 hours per day throughout the year, generating 365,000 MWh. What is the Plant Use Factor?

  1. ((a))

    85%

  2. ((b))

    50%

  3. ((c))

    70%

  4. ((d))

    90%

Show Answer
Answer: ((a))

85%

112

A diode rectifier circuit has an AC input voltage of 230 Vrms and a load resistance of 1 kΩ with a capacitor. The primary function of the capacitor is to:

  1. ((a))

    increase the output voltage

  2. ((b))

    decrease the output voltage

  3. ((c))

    filter out the AC ripples and smooth the output voltage

  4. ((d))

    regulate the output voltage 

Show Answer
Answer: ((a))

increase the output voltage

113

The phasor representation of current and voltage in a pure inductive circuit shows that _______.

  1. ((a))

    voltage leads current by 90° 

  2. ((b))

    current and voltage are in phase

  3. ((c))

    voltage leads current by 180°

  4. ((d))

    current leads voltage by 90°

Show Answer
Answer: ((a))

voltage leads current by 90° 

114

Select the option that is correct regarding the following two statements labelled Assertion (A) and Reason (R).

Assertion (A): The neutral wire in a star-connected balanced three-phase system carries no current.

Reason (R): In a balanced system, the sum of the three-phase current phasors is always zero.

  1. ((a))

    A is true, but R is false.

  2. ((b))

    A is false, but R is true

  3. ((c))

    Both A and R are true, but R is not the correct explanation of A

  4. ((d))

    Both A and R are true, and R is the correct explanation of A. 

Show Answer
Answer: ((a))

A is true, but R is false.

115

In an induction type directional overcurrent relay, what is the net torque at the balance point when the relay is on the verge of operating? 

  1. ((a))

    Equal to K2

  2. ((b))

    Equal to VI cos (ɵ - α)

  3. ((c))

    Equal to the pick-up torque of the relay 

  4. ((d))

    Equal to zero

Show Answer
Answer: ((a))

Equal to K2

116

What is a key advantage of voltage drop in a radial power distribution system?

  1. ((a))

    It increases power dissipation in the form of heat. 

  2. ((b))

    It ensures voltage remains constant throughout the network. 

  3. ((c))

    It eliminates the need for voltage regulators

  4. ((d))

    It limits excessive current flow, aiding in overcurrent protection.

Show Answer
Answer: ((a))

It increases power dissipation in the form of heat. 

117

How does a ring main system improve reliability?

  1. ((a))

    It reduces the number of distributors.

  2. ((b))

    It allows power to be supplied from two directions. 

  3. ((c))

    It reduces voltage drop in the system.

  4. ((d))

    It eliminates the need for a transformer. 

Show Answer
Answer: ((a))

It reduces the number of distributors.

118

What does the use of a single winding in an auto transformer result in?

  1. ((a))

    Higher losses

  2. ((b))

    Reduced copper consumption

  3. ((c))

    Lower voltage regulation

  4. ((d))

    Increased size and weight

Show Answer
Answer: ((a))

Higher losses

119

Which of the following statements is/are true?

Statement (I): High voltage drop in residential areas can cause lights to dim or flicker.

Statement (II): Voltage drop occurs due to excessive power consumption in a household.

  1. ((a))

    Only Statement (II) is true.

  2. ((b))

    Neither Statement (I) nor Statement (II) is true.

  3. ((c))

    Only Statement (I) is true

  4. ((d))

    Both Statement (I) and Statement (II) are true.

Show Answer
Answer: ((a))

Only Statement (II) is true.

120

Which of the following is a common application of universal motors?

  1. ((a))

    Refrigerators

  2. ((b))

    Vacuum cleaners

  3. ((c))

    Ceiling fans

  4. ((d))

    Air conditioners

Show Answer
Answer: ((a))

Refrigerators

121

Which of the following is a significant feature of Scott connection transformers?

  1. ((a))

    They provide high voltage output

  2. ((b))

    They convert 1-phase power into 3-phase

  3. ((c))

    They provide a 2-phase output from a 3-phase input. 

  4. ((d))

    They are used for stepping down voltage only.

Show Answer
Answer: ((a))

They provide high voltage output

122

What is the primary cause of junction capacitance in a p-n diode?

  1. ((a))

    Variation in minority carrier concentration with applied voltage

  2. ((b))

    Thermal generation of carriers in the depletion region

  3. ((c))

    Change in depletion region width with applied voltage

  4. ((d))

    Variation in majority carrier concentration with applied voltage

Show Answer
Answer: ((a))

Variation in minority carrier concentration with applied voltage

123

What is the induced EMF called in a DC motor, which opposes the flow of current in the armature conductors?

  1. ((a))

    Field EMF

  2. ((b))

    Back EMF

  3. ((c))

    Induced voltage

  4. ((d))

    Supply EMF

Show Answer
Answer: ((a))

Field EMF

124

Torque in reluctance motors is produced primarily due to? 

  1. ((a))

    Permanent magnet alignment 

  2. ((b))

    Induction principles

  3. ((c))

    Magnetic saliency

  4. ((d))

    Eddy current generation

Show Answer
Answer: ((a))

Permanent magnet alignment 

125

In a Synchronous reluctance motor, flux barriers are typically filled with _____________

  1. ((a))

    Ferrite

  2. ((b))

    Copper

  3. ((c))

    Laminated steel 

  4. ((d))

    Air or non-magnetic material 

Show Answer
Answer: ((a))

Ferrite

126

For a BJT, determine the emitter current if the collector current is 1 mA and the common base short circuit amplification factor is unity. 

  1. ((a))

    1.5 mA

  2. ((b))

    2 mA

  3. ((c))

    1 mA

  4. ((d))

    0.5 mA

Show Answer
Answer: ((a))

1.5 mA

127

For a Zener diode working in reverse bias condition, the Zener current is _________ for supply voltage _________ the Reverse Zener breakdown voltage. 

  1. ((a))

    close to zero; greater than

  2. ((b))

    close to zero; less than

  3. ((c))

    close to infinity; greater than

  4. ((d))

    close to infinity; less than 

Show Answer
Answer: ((a))

close to zero; greater than

128

Which of the following is NOT an advantage of the underground system over the overhead system?

  1. ((a))

    Reduced voltage drops

  2. ((b))

    Better aesthetics and safety

  3. ((c))

    Lower chances of power failures

  4. ((d))

    Tapping for loads and service mains is easier

Show Answer
Answer: ((a))

Reduced voltage drops

129

How can eddy current loss be reduced in the armature core?

  1. ((a))

    By increasing the motor's speed

  2. ((b))

    By increasing the core resistance

  3. ((c))

    By using a high resistance core material

  4. ((d))

    By laminating the core to reduce the flow of eddy currents

Show Answer
Answer: ((a))

By increasing the motor's speed

130

What is a critical factor in the selection of cables for outdoor public lighting installations? 

  1. ((a))

    Ignoring voltage drop calculations to reduce costs. 

  2. ((b))

    The cable's ability to withstand environmental conditions and carry the required current safely

  3. ((c))

    Selecting the cheapest cable available. 

  4. ((d))

    The colour of the cable insulation

Show Answer
Answer: ((a))

Ignoring voltage drop calculations to reduce costs. 

131

Why do inverted V-curves have an inverted "V" shape ?

  1. ((a))

    Mechanical load affects excitation linearly

  2. ((b))

    Power factor peaks at optimal excitation (unity PF)

  3. ((c))

    Stator resistance varies non-linearly with excitation

  4. ((d))

    Armature current peaks at unity power factor

Show Answer
Answer: ((a))

Mechanical load affects excitation linearly

132

The S.I. unit of work is ______ and energy is ______.

  1. ((a))

    Watt; Joule

  2. ((b))

    Newton; Newton

  3. ((c))

    Joule; Joule

  4. ((d))

    Joule; Newton

Show Answer
Answer: ((a))

Watt; Joule

133

The maximum fault current reached before a fuse melts is called:

  1. ((a))

    rupturing current

  2. ((b))

    holding current

  3. ((c))

    cut-off current

  4. ((d))

    peak current

Show Answer
Answer: ((a))

rupturing current

134

Inductance of a coil ___________ when we place an iron bar inside it.

  1. ((a))

    reduces to zero

  2. ((b))

    increases

  3. ((c))

    remains unchanged

  4. ((d))

    decreases

Show Answer
Answer: ((a))

reduces to zero

135

A hydro power plant with an installed capacity of 10 MW falls under which of the following categories?

  1. ((a))

    Small hydro

  2. ((b))

    Mini hydro

  3. ((c))

    Medium hydro

  4. ((d))

    Large hydro

Show Answer
Answer: ((a))

Small hydro

136

One big CHALLENGE with Solar Panels (PV) compared to Concentrating Solar Power (CSP) is:

  1. ((a))

    they have lots of moving parts, making maintenance costly

  2. ((b))

    they need costly batteries to store power for nighttime use

  3. ((c))

    they completely stop working on cloudy days

  4. ((d))

    they need high-tech factories to be made 

Show Answer
Answer: ((a))

they have lots of moving parts, making maintenance costly

137

A current impulse signal of 4 δ(t) is forced through a capacitor C. The voltage Vc (t) across capacitor is given by: 

  1. ((a))

    4Ct\rm \frac{4}{C}t

  2. ((b))

    4.u(t)C\rm \frac{4.u(t)}{C}

  3. ((c))

    4.u(t)-C

  4. ((d))

    4.t

Show Answer
Answer: ((a))

4Ct\rm \frac{4}{C}t

138

Match the following sources of error in a CT with their corresponding causes

Error TypeCause
1.Ratio ErrorA.Leakage flux in windings
2.Phase Angle ErrorB.Magnetising current requirement
3.Hysteresis ErrorC.Non-ideal core material properties
4.Leakage Reactance ErrorD.Residual magnetism in the core
  1. ((a))

    1 → A, 2 → B, 3 → D, 4 → C

  2. ((b))

    1 → B, 2 → A, 3 → D, 4 → C

  3. ((c))

    1 → B, 2 → C, 3 → D, 4 → A

  4. ((d))

    1 → B, 2 → A, 3 → C, 4 → D

Show Answer
Answer: ((a))

1 → A, 2 → B, 3 → D, 4 → C

139

Ohm's law for a magnetic circuit is given by ratio of: 

  1. ((a))

    magnetic reluctance to magnetic flux 

  2. ((b))

    magnetic reluctance to magnetomotive force

  3. ((c))

    magnetomotive force to magnetic reluctance

  4. ((d))

    magnetomotive force to permeance 

Show Answer
Answer: ((a))

magnetic reluctance to magnetic flux 

140

What is the primary purpose of preparing a material schedule and detailed estimation for an industrial installation? 

  1. ((a))

    To provide a comprehensive list of materials and costs for accurate project planning and execution

  2. ((b))

    To eliminate the need for protective devices in the system

  3. ((c))

    To focus only on the aesthetic aspects of the installation

  4. ((d))

    To ensure the project is completed without any documentation

Show Answer
Answer: ((a))

To provide a comprehensive list of materials and costs for accurate project planning and execution

141

In a Francis turbine, which of the following components dynamically adjust(s) to regulate the flow rate and optimise power output under varying load conditions?

  1. ((a))

    Guide vanes

  2. ((b))

    Spiral casing

  3. ((c))

    Draft tube

  4. ((d))

    Runner blades

Show Answer
Answer: ((a))

Guide vanes

142

Which of the following statements best describes the benefit of a Power Factor Tariff in energy conservation?

  1. ((a))

    It increases the overall electricity cost regardless of power factor improvement

  2. ((b))

    It has no impact on energy conservation or system efficiency. 

  3. ((c))

    It only applies to residential consumers and does not affect industrial or commercial users.

  4. ((d))

    It encourages consumers to maintain a high power factor, reducing losses and improving system efficiency. 

Show Answer
Answer: ((a))

It increases the overall electricity cost regardless of power factor improvement

143

For a voltage divider bias circuit in CE configuration using NPN BJT transistor, Vcc = 10 V and the resistance at collector and emitter is Rc = 2 kΩ and RE = 500 Ω, respectively. (Assume DC current gain Beta of transistor as very high) Determine the approximate maximum value of collector current for the voltage divider bias circuit.

  1. ((a))

    5 mA

  2. ((b))

    4 mA

  3. ((c))

    2.5 mA

  4. ((d))

    20 mA

Show Answer
Answer: ((a))

5 mA

144

Select the correct advantage of a full-wave rectifier over a half-wave rectifier

  1. ((a))

    Lower efficiency and utilisation of only one half-cycle of the AC input

  2. ((b))

    Lower cost

  3. ((c))

    Higher efficiency and utilisation of both half-cycles of the AC input

  4. ((d))

    Lower output voltage

Show Answer
Answer: ((a))

Lower efficiency and utilisation of only one half-cycle of the AC input

145

What is a critical consideration in the design and estimation of street lighting costs?

  1. ((a))

    Calculating the number of light fixtures, cable requirements, and energy consumption to determine overall costs

  2. ((b))

    Focusing only on the aesthetic design of the streetlights

  3. ((c))

    Ignoring energy efficiency to reduce initial costs

  4. ((d))

    Eliminating the use of protective devices in the system

Show Answer
Answer: ((a))

Calculating the number of light fixtures, cable requirements, and energy consumption to determine overall costs

146

For small capacity motors (up to 3 Hp), what voltage can be applied at startup? 

  1. ((a))

    Zero voltage

  2. ((b))

    Double the normal voltage

  3. ((c))

    Half the normal voltage 

  4. ((d))

    Full normal voltage

Show Answer
Answer: ((a))

Zero voltage

147

Force acting on two parallel current-carrying conductors is __________, if the current is in the same direction.

  1. ((a))

    zero

  2. ((b))

    infinite

  3. ((c))

    repulsive

  4. ((d))

    attractive

Show Answer
Answer: ((a))

zero

148

An alternating current is one whose magnitude ______ and direction ______. 

  1. ((a))

    changes continuously; changes periodically 

  2. ((b))

    does not change; remains the same

  3. ((c))

    does not change; changes periodically

  4. ((d))

    changes continuously; remain the same

Show Answer
Answer: ((a))

changes continuously; changes periodically 

149

Copper losses in a transformer are proportional to:

  1. ((a))

    the square of the load current

  2. ((b))

    the square of the frequency

  3. ((c))

    the square of the turns ratio

  4. ((d))

    the square of the voltage 

Show Answer
Answer: ((a))

the square of the load current

150

Which of the following parameters can be controlled by an AC/DC drive? 

  1. ((a))

    Speed, torque and horsepower

  2. ((b))

    Torque, direction of AC motor and speed

  3. ((c))

    Speed and torque

  4. ((d))

    Speed, torque, horsepower, and direction of AC motor

Show Answer
Answer: ((a))

Speed, torque and horsepower

Attempt this paper under real exam conditions

Timed interface, section switching, instant scoring, and question-by-question analytics — free.

Start Timed Attempt