Full-Length Mock Test 6 — RRB JE CBT 2 Technical Abilities Pattern (100 MCQs)

Section A: Circuit Fundamentals and AC/DC Basics (20 Questions)

1. A "conductance" (G) is defined as:
   (a) The reciprocal of resistance (1/R) (b) The product of resistance and voltage (c) The reciprocal of voltage (d) The square of resistance
2. "Susceptance" (B) is defined as:
   (a) The reciprocal of reactance (1/X) (b) The product of reactance and current (c) The reciprocal of voltage (d) The square of reactance
3. "Admittance" (Y) is defined as:
   (a) The reciprocal of impedance (1/Z) (b) The product of impedance and current (c) The square of impedance (d) The reciprocal of voltage
4. A circuit's "power factor" can also be expressed as the ratio of:
   (a) Active power to apparent power (b) Reactive power to apparent power exclusively, with no relation to active power (c) Apparent power to reactive power exclusively (d) Resistance to reactance directly with no power terms involved
5. The concept of "conjugate matching" for maximum power transfer, extended to AC circuits with reactive elements, requires the load impedance to be the:
   (a) Complex conjugate of the source impedance (b) Exact same magnitude, but purely resistive regardless of source reactance (c) Twice the source impedance's magnitude (d) Half the source impedance's magnitude, purely resistive
6. In per-unit system representation, commonly used in power system analysis, quantities are expressed as:
   (a) A ratio relative to a chosen base value (b) Only in absolute SI units, with no ratio-based representation (c) Only as percentages of the maximum possible value in the universe (d) Only as whole numbers with no fractional representation permitted
7. The per-unit system is particularly useful in power system analysis because it:
   (a) Simplifies calculations across different voltage levels via transformers (b) Makes calculations more complex with no simplification benefit (c) Eliminates the need for any transformer modelling (d) Applies only to DC systems, never AC power systems
8. A "single-phase" AC supply has how many live conductors carrying the main power (excluding neutral/earth)?
   (a) One (b) Two (c) Three (d) Four
9. A "two-wire DC" system typically consists of:
   (a) A positive and a negative conductor (b) Three phase conductors with no DC polarity concept (c) A single conductor with no return path (d) Four conductors with two neutrals
10. The "form factor" of a waveform is the ratio of:
    (a) RMS value to average value (b) Peak value to RMS value (c) Average value to peak value (d) Peak value to average value directly with no RMS involvement
11. The "peak factor" (crest factor) of a waveform is the ratio of:
    (a) Peak value to RMS value (b) RMS value to average value (c) Average value to peak value (d) RMS value to peak value inverted with no other meaning
12. For a square wave, the RMS value is:
    (a) Equal to its peak value (b) Always zero regardless of peak value (c) Always exactly 0.707 times peak, identical to a sine wave (d) Always exactly 0.637 times peak, identical to a half-wave rectified sine
13. A "balanced load" in a three-phase system draws:
    (a) Equal current magnitude in each phase, with the expected 120-degree phase relationship (b) Completely arbitrary, unequal current in each phase with no defined relationship (c) Current only in one phase, with the other two completely unused (d) DC current only, with no AC component
14. An "unbalanced load" in a three-phase system results in:
    (a) Unequal phase currents, potentially requiring a neutral current path (b) Perfectly equal phase currents identical to a balanced load in every respect (c) Complete absence of any current in all three phases (d) Automatic correction with no engineering consideration needed
15. In a three-phase four-wire system, the "neutral" conductor is generally sized:
    (a) Based on expected unbalance current, sometimes smaller than phase conductors for balanced/near-balanced loads (b) Always significantly larger than any phase conductor regardless of load balance (c) Identical to earth conductors in every single installation with no distinction (d) With no defined sizing consideration at all
16. "Power factor" of an inductive load can be improved to closer to unity by adding:
    (a) A capacitor in parallel with the load (b) An additional inductor in parallel with the load (c) A resistor in series with the load exclusively (d) No component can ever improve power factor
17. Series RLC circuit "impedance" below resonant frequency is generally:
    (a) Capacitive (net reactance is capacitive) (b) Purely resistive at all frequencies below resonance (c) Inductive (net reactance is inductive) at all frequencies below resonance without exception (d) Undefined below resonance
18. Series RLC circuit "impedance" above resonant frequency is generally:
    (a) Inductive (net reactance is inductive) (b) Purely resistive at all frequencies above resonance (c) Capacitive (net reactance is capacitive) at all frequencies above resonance without exception (d) Undefined above resonance
19. A parallel RLC circuit exhibits "anti-resonance" (or parallel resonance) at a frequency where circuit impedance is generally:
    (a) At or near its maximum value (b) At or near its minimum value, identical to series resonance (c) Exactly zero at anti-resonance (d) Infinite at all frequencies, not just at anti-resonance
20. Understanding resonance behaviour (series and parallel) is relevant to practical applications such as:
    (a) Filter design and tuned circuits (b) Only purely theoretical exercises with no practical application (c) Only concrete mix design, with no electrical relevance (d) Only soil classification, with no electrical relevance

Section B: Electrical Machines (20 Questions)

21. A "DC motor's mechanical power output" is given (in terms of back EMF Eb and armature current Ia) approximately by:
    (a) Eb × Ia (b) Eb / Ia (c) Eb + Ia (d) Eb − Ia
22. As armature current increases in a DC series motor (before magnetic saturation), motor torque:
    (a) Increases roughly with the square of current (b) Decreases as current increases (c) Remains exactly constant regardless of current (d) Becomes negative
23. A DC motor's "speed regulation" is defined similarly to a generator's voltage regulation, relating:
    (a) No-load speed to full-load speed (b) Only the machine's physical size (c) Only its manufacturer (d) Only its paint colour
24. Which DC motor type exhibits the best (most nearly constant) speed regulation?
    (a) Shunt motor (b) Series motor (c) A motor with no field winding of any kind (d) None; all DC motor types have identical speed regulation
25. A transformer connected in "Yy0" vector group has primary and secondary windings connected in:
    (a) Star-star, with zero phase displacement (b) Delta-delta exclusively (c) Star-delta exclusively (d) An undefined configuration with no star/delta relationship
26. A transformer connected in "Dd0" vector group has primary and secondary windings connected in:
    (a) Delta-delta, with zero phase displacement (b) Star-star exclusively (c) Star-delta exclusively (d) An undefined configuration
27. A "Scott connection" of transformers is used to convert:
    (a) Three-phase supply to two-phase supply (or vice versa) (b) DC to AC exclusively, with no relation to phase conversion (c) AC to DC exclusively, with no relation to phase conversion (d) Single-phase to exactly six-phase supply exclusively, with no other conversion possible
28. A transformer's "inrush current" refers to:
    (a) A brief, high-magnitude current surge when the transformer is first energised (b) The transformer's steady-state rated current under normal load (c) A current that flows only during a short-circuit fault, never at energisation (d) A purely theoretical concept with no real transformer exhibiting it
29. Transformer inrush current is primarily caused by:
    (a) Core saturation effects during the initial energisation transient (b) Steady-state copper losses exclusively (c) Steady-state iron losses exclusively (d) The load's power factor exclusively, with no relation to energisation
30. An induction motor's "starting current," without any starting method applied, is generally:
    (a) Several times its rated full-load current (b) Always lower than its rated full-load current (c) Exactly equal to its rated full-load current in every case (d) Zero at the instant of starting
31. Direct-on-line (DOL) starting of an induction motor is generally suitable for:
    (a) Relatively small motors where starting current surge is acceptable to the supply system (b) Only very large motors exclusively, regardless of supply capacity (c) No motor of any size (d) Only synchronous motors, never induction motors
32. A "star-delta starter's" reduction in starting current/torque, compared to direct-on-line starting, is approximately a factor of:
    (a) One-third (b) Exactly ten times (c) No reduction whatsoever (d) An increase, rather than reduction, in starting current
33. An induction motor's "efficiency" generally peaks at a loading level:
    (a) Somewhat below full rated load, for many practical machine designs (b) Always at exactly zero load (c) Always at exactly 200 percent of rated load (d) Completely independent of loading level
34. Which of the following best describes "cogging torque" in a permanent magnet motor?
    (a) A torque ripple caused by interaction between permanent magnets and stator slots, even with no current applied (b) The motor's total continuous rated torque under normal operation (c) A beneficial, smoothing torque component with no ripple effect (d) A phenomenon exclusive to wound-rotor induction motors, never PM motors
35. A synchronous motor operating at "unity power factor" draws:
    (a) Current exactly in phase with voltage, with no reactive component (b) Current at 90 degrees out of phase with voatage, purely reactive (c) No current whatsoever (d) Only DC current, with no AC component
36. Over-exciting a synchronous motor's field, beyond that needed for unity power factor, generally causes it to operate at a:
    (a) Leading power factor (b) Lagging power factor (c) Exactly zero power factor under all over-excitation levels (d) Power factor unrelated to excitation level
37. Under-exciting a synchronous motor's field, below that needed for unity power factor, generally causes it to operate at a:
    (a) Lagging power factor (b) Leading power factor (c) Exactly unity power factor regardless of under-excitation (d) Power factor unrelated to excitation level
38. A synchronous generator's terminal voltage, for a given field excitation, generally decreases as load current increases for:
    (a) An inductive (lagging power factor) load (b) A purely resistive load exclusively, with no other load type showing this effect (c) No load type whatsoever (d) Only a leading power factor load, never a lagging load
39. A synchronous generator's terminal voltage may actually rise with increasing load current for:
    (a) A sufficiently leading (capacitive) power factor load (b) A purely resistive load exclusively (c) No load type whatsoever (d) Only an inductive load, never a capacitive load
40. Overall, understanding voltage/current/power-factor behaviour of synchronous machines under varying excitation and load is relevant to RRB JE Electrical preparation because:
    (a) These principles underlie reactive power control practices in real power systems (b) They have no relevance to any electrical engineering role (c) Only machine designers, never JEs, need this understanding (d) This knowledge is tested only in interviews, never the written exam

Section C: Power Systems and Protection (20 Questions)

41. A "capacitor voltage transformer" (CVT), used at high transmission voltages, provides a lower-cost alternative to a conventional PT primarily by:
    (a) Using a capacitive voltage divider combined with an intermediate transformer (b) Using an entirely mechanical, non-electrical measurement principle (c) Requiring no voltage measurement of any kind (d) Operating only on DC systems, never AC transmission
42. A "current-limiting fuse," compared to a standard fuse, is designed to:
    (a) Interrupt very high fault currents quickly, limiting peak let-through current (b) Allow unlimited fault current to flow with no limiting effect (c) Operate only at extremely low currents, never high fault currents (d) Serve only as a decorative marker with no protective function
43. "Arc flash" hazard in electrical switchgear refers to the risk of:
    (a) A sudden release of energy from an electric arc fault, posing severe burn/injury risk (b) A purely cosmetic visual effect with no safety implication (c) A beneficial lighting effect with no hazard (d) A phenomenon exclusive to low-voltage household circuits, never switchgear
44. Arc-flash risk assessment/labelling on equipment is intended to help workers:
    (a) Select appropriate PPE and safe working procedures before working on energised equipment (b) Ignore all safety precautions entirely (c) Serve only a decorative labelling function with no safety guidance (d) Avoid the need for any PPE whatsoever
45. A "protective relay's" pickup setting refers to:
    (a) The threshold value at which the relay begins to operate (b) Only the relay's physical size (c) Only the relay's manufacturer (d) Only the relay's colour
46. A relay's "time-current characteristic curve" (e.g., inverse-definite-minimum-time, IDMT) shows the relationship between:
    (a) Fault current magnitude and the relay's operating time (b) Only the relay's cost and its physical size (c) Only ambient temperature and relay colour (d) No meaningful relationship; the curve is purely decorative
47. An "inverse-time" overcurrent relay characteristic means that, as fault current increases:
    (a) The relay's operating time decreases (b) The relay's operating time increases (c) The relay's operating time remains exactly constant regardless of current (d) The relay never operates regardless of current magnitude
48. A "definite-time" overcurrent relay characteristic means the relay operates:
    (a) After a fixed time delay, regardless of the exact fault current magnitude above pickup (b) Instantaneously with zero delay under all conditions (c) Only after a randomly varying, unpredictable time delay (d) Never, regardless of fault current
49. An "instantaneous" overcurrent relay element operates:
    (a) With no intentional time delay, for very high fault currents (b) Only after an extremely long, multi-hour delay (c) Only for currents below the pickup setting (d) Never, under any fault condition
50. "Directional" overcurrent protection is used particularly in systems with:
    (a) Possible fault current flow in either direction, such as ring/interconnected networks (b) Only a single, fixed direction of power flow with no possible reversal, ever (c) No relevance to any real power system configuration (d) Only DC systems, never AC systems
51. A "restricted earth fault" (REF) protection scheme is commonly applied to:
    (a) Transformers/generators, for sensitive detection of earth faults within a defined zone (b) Only overhead transmission lines, never transformers (c) Only household wiring, never large equipment (d) No practical application in power systems
52. "Negative sequence" protection on a generator/motor is used to detect:
    (a) Unbalanced supply conditions that can cause overheating (b) Only perfectly balanced conditions, with no unbalance detection (c) Only mechanical vibration, with no electrical relevance (d) Only DC offset, with no relevance to AC unbalance
53. "Loss of excitation" protection on a synchronous generator detects:
    (a) A failure of field excitation, which can cause the machine to behave abnormally, potentially like an induction generator (b) Only a mechanical bearing failure, with no relation to excitation (c) Only a cooling system failure, with no relation to excitation (d) No condition relevant to synchronous generator operation
54. "Reverse power" protection on a generator is used to detect:
    (a) The generator absorbing power from the grid rather than supplying it (indicating prime mover failure) (b) Only excessive power supplied to the grid, with no relation to power direction (c) Only a cooling system malfunction (d) No condition relevant to generator operation
55. Which of the following best describes "under-voltage" protection?
    (a) Detecting and responding to voltage falling below a set threshold (b) Detecting only overvoltage conditions, never undervoltage (c) Detecting only frequency deviations, with no relation to voltage (d) A concept with no practical protective application
56. Which of the following best describes "over-voltage" protection?
    (a) Detecting and responding to voltage rising above a set threshold (b) Detecting only undervoltage conditions, never overvoltage (c) Detecting only frequency deviations, with no relation to voltage (d) A concept with no practical protective application
57. A "differential protection scheme's" main advantage over simple overcurrent protection is its:
    (a) High sensitivity and selectivity, confined to a clearly defined protected zone (b) Complete inability to detect any fault whatsoever (c) Requirement for no current transformers of any kind (d) Applicability only to very low-voltage household circuits
58. Which of the following best describes a key limitation practical engineers must consider with differential protection schemes?
    (a) Current transformer accuracy/matching across the protected zone (b) No limitation exists; the scheme is entirely free of any practical consideration (c) Complete independence from current transformer performance (d) Applicability only to DC systems, never AC systems
59. Testing and commissioning of a new protection scheme before energisation typically includes:
    (a) Verifying relay settings, CT/PT connections, and simulated fault response (b) Only a visual inspection of paint colour with no functional testing (c) No testing of any kind; schemes are assumed correct without verification (d) Testing only after a real fault has already occurred in service
60. Overall, protective relaying concepts (pickup, time-current characteristics, differential/directional schemes) are important for RRB JE Electrical candidates because:
    (a) They reflect real technical knowledge applied in power system operation/maintenance (b) They have no relevance to any electrical engineering role (c) Only specialist protection engineers, never JEs, need this understanding (d) This knowledge is tested only in interviews, never the written exam

Section D: Measurements, Electronics, Control, and Power Electronics (20 Questions)

61. A "Wien bridge oscillator" is a common circuit used to generate:
    (a) Sinusoidal AC signals at a specific frequency (b) Only a fixed DC output with no AC component (c) Only digital square-wave logic signals, never sinusoidal output (d) Only random noise with no defined frequency
62. A "voltage-controlled oscillator" (VCO) produces an output frequency that varies with:
    (a) An applied control voltage (b) Only the ambient temperature, with no voltage dependence (c) Only the circuit's physical colour (d) Only the circuit's manufacturer
63. A "phase-locked loop" (PLL) is commonly used to:
    (a) Synchronise an oscillator's output phase/frequency to a reference input signal (b) Only measure DC resistance with no relation to oscillators (c) Only generate mechanical torque (d) Only measure temperature
64. Which of the following best describes a "microprocessor" (as distinct from a full microcontroller)?
    (a) A CPU on a single chip, typically requiring external memory/peripheral chips (b) A complete system with integrated memory/peripherals on one chip, identical to a microcontroller in every respect (c) A purely mechanical device with no digital processing (d) A type of passive resistor network
65. Which of the following best describes an "embedded system"?
    (a) A dedicated computing system designed to perform specific functions within a larger device/system (b) A general-purpose desktop computer with no specific dedicated function (c) A purely mechanical device with no computing element (d) A concept unrelated to modern electrical/electronic equipment
66. A "real-time operating system" (RTOS), used in some embedded/control applications, is characterised by:
    (a) Deterministic, timely response to events within specified time constraints (b) Completely unpredictable, arbitrary response timing with no guarantees (c) No practical use in any control application (d) Exclusive use in non-time-critical desktop applications only
67. "Signal conditioning" of a raw sensor output typically involves processes such as:
    (a) Amplification, filtering, and linearisation before further processing (b) Only physically discarding the sensor's output with no further use (c) Only converting the signal into audible sound with no other processing (d) Only converting the signal into visible light with no other processing
68. An "isolation amplifier" is used in signal conditioning primarily to:
    (a) Provide electrical isolation between a sensor circuit and downstream processing circuitry (b) Increase electrical connection between circuits, eliminating any isolation (c) Serve only a decorative function with no isolation benefit (d) Replace the need for any sensor
69. A "current loop" (e.g., 4-20 mA) signal transmission standard is commonly used in industrial instrumentation because it offers:
    (a) Good noise immunity over relatively long cable runs (b) Extremely poor noise immunity, worse than voltage signals, with no practical benefit (c) No practical application in modern instrumentation (d) Use exclusively for very short cable runs of a few centimetres
70. A "4-20 mA" current loop signal's "live zero" (4 mA representing the zero/minimum process value) allows a receiving instrument to distinguish:
    (a) A genuine zero reading from a broken/faulty signal wire (giving 0 mA) (b) Nothing useful; 4 mA and 0 mA are treated identically in every system (c) Only the wire's physical colour (d) Only the ambient temperature, unrelated to the actual measured signal
71. A "fieldbus" communication protocol (e.g., Modbus, Profibus) in industrial automation allows:
    (a) Digital communication between multiple field devices/controllers over a shared network (b) Only a single, isolated point-to-point analog connection with no digital/networked capability (c) No communication of any kind between devices (d) Only mechanical, non-electrical signalling
72. Which of the following best describes "Industry 4.0" concepts as increasingly relevant to modern electrical/industrial engineering?
    (a) Integration of automation, data exchange, IoT, and smart technologies in industrial processes (b) A concept with no relevance to industrial/electrical engineering (c) A purely historical, now-obsolete concept (d) A concept applicable only to non-technical office administration
73. A "power factor meter" is used to directly measure:
    (a) The power factor (cos φ) of an AC circuit (b) Only DC resistance (c) Only mechanical torque (d) Only illumination level
74. A "synchroscope" is used to:
    (a) Indicate the phase relationship between two AC sources before synchronising (paralleling) them (b) Measure DC resistance directly (c) Measure mechanical vibration (d) Measure illumination level
75. Correct synchronising of an alternator to the grid typically requires matching:
    (a) Voltage magnitude, frequency, and phase sequence/angle (b) Only physical rotor size (c) Only manufacturer brand (d) Only paint colour of the machine casing
76. Which of the following best describes a key hazard of synchronising an alternator to the grid with an incorrect phase relationship?
    (a) Potentially damaging transient currents/mechanical stress at the moment of connection (b) No hazard whatsoever under any phase mismatch condition (c) Only a minor, purely cosmetic indicator light discrepancy (d) A hazard relevant only to DC systems, never AC synchronising
77. A "watt-hour meter's" creep test is used to check for:
    (a) Unwanted meter registration with no load connected (b) Only the meter's physical weight (c) Only the meter's colour (d) Only the meter's manufacturer details
78. A power system's "harmonics analysis" using instruments/software helps engineers to:
    (a) Identify and quantify harmonic distortion sources/levels for corrective action (b) Increase harmonic distortion deliberately (c) Serve only a decorative reporting function with no corrective value (d) Replace the need for any protective relay
79. "Active harmonic filters," compared to passive filters, generally offer:
    (a) More adaptable, dynamic harmonic compensation across varying conditions (b) No harmonic compensation capability whatsoever (c) Use exclusively in DC systems, never AC systems (d) Identical, fixed-frequency-only compensation with no adaptability
80. Overall, modern instrumentation, automation, and industrial communication topics reflect the reality that:
    (a) Electrical engineering practice increasingly integrates digital technology alongside traditional principles (b) These topics have no relevance to practical electrical engineering (c) Only computer science graduates need this knowledge (d) These topics are tested only at postgraduate level

Section E: General Awareness, Computer Applications, and Current Affairs (20 Questions)

81. Which of the following best describes India's "PM Surya Ghar: Muft Bijli Yojana" scheme?
    (a) A scheme promoting rooftop solar installation for households with subsidy support (b) A railway electrification scheme (c) A banking reform scheme (d) A space research scheme
82. Which of the following best describes India's approach to grid integration of increasing renewable energy capacity?
    (a) Investments in grid strengthening, storage, and flexible generation to accommodate variability (b) Complete rejection of any renewable integration effort (c) Reliance solely on traditional thermal generation with no grid adaptation (d) No relevance to the power sector
83. Which of the following best describes "green energy open access" rules in India's power sector?
    (a) Facilitating consumer access to renewable power through the grid, often at lower thresholds than conventional open access (b) Restricting all renewable power access entirely (c) A rule unrelated to electricity access (d) A rule applicable only to railway electricity consumption
84. Which of the following best describes the "National Mission on Enhanced Energy Efficiency" (NMEEE)?
    (a) A mission under India's climate action plan focused on improving energy efficiency (b) A mission focused solely on space research (c) A mission focused solely on banking reform (d) A mission focused solely on railway ticketing
85. Which of the following best describes the general trend in global/Indian data centre growth and its relevance to power systems?
    (a) Increasing electricity demand from data centres, requiring careful grid capacity planning (b) A trend with no relevance to electrical/power engineering (c) A trend causing decreasing electricity demand nationally (d) A trend relevant only to railway signalling, not power systems
86. In computing, "5G" technology refers to:
    (a) The fifth generation of mobile network technology, offering higher speed/lower latency (b) A type of concrete grade (c) A type of surveying instrument (d) A type of construction admixture
87. Which of the following best describes "blockchain" technology, sometimes discussed for energy trading applications?
    (a) A distributed digital ledger recording transactions across multiple systems (b) A type of physical construction material (c) A type of surveying instrument (d) A type of concrete admixture
88. Which of the following best describes "peer-to-peer energy trading," an emerging concept enabled by digital platforms?
    (a) Direct electricity trading between prosumers (e.g., rooftop solar owners) and consumers, often via a digital platform (b) A method of concrete curing (c) A method of soil stabilisation (d) A method of surveying
89. Which of the following best describes "virtual power plants" (VPPs), an emerging grid-management concept?
    (a) Aggregating distributed energy resources (solar, storage, demand response) to act as a coordinated resource (b) A single, large, physically centralised power station only (c) A method of concrete curing (d) A method of soil stabilisation
90. Which of the following best describes the relevance of the RRB JE General Awareness section's coverage of power-sector current affairs to Electrical candidates?
    (a) It tests awareness of developments relevant to their future employer and sector (b) It is entirely unrelated to the recruiting organisation (c) It only tests unrelated general knowledge with no sector relevance (d) It replaces the technical section entirely
91. Which of the following best describes why candidates should track updates to government schemes/technology trends close to their exam date?
    (a) Current affairs content evolves, and recent developments are more likely to be freshly tested (b) Current affairs content never changes once published (c) Only content from many years ago is ever tested (d) Current affairs has no relevance to the RRB JE exam
92. Which of the following best describes the overall structure of a well-rounded RRB JE Electrical Engineering revision plan in the final weeks before the exam?
    (a) A mix of concept revision, formula capsules, and full-length mock test practice (b) Exclusively re-reading theory with no practice questions (c) Exclusively solving mock tests with no concept revision (d) No structured plan; purely random, unplanned study
93. Which of the following best describes why understanding the "why" behind formulas benefits exam performance?
    (a) It helps correctly apply formulas to varied question phrasings and avoid careless errors (b) It has no benefit over pure rote memorisation (c) It only helps with essay-based exams, never MCQ-based exams (d) It slows down performance with no compensating benefit
94. Which of the following best describes a sound approach to managing negative marking during the exam?
    (a) Attempting questions confidently answered or where at least one option can be reliably eliminated (b) Attempting every single question regardless of confidence, with pure random guessing throughout (c) Never attempting any question with any uncertainty whatsoever (d) Ignoring the technical section entirely due to negative marking concerns
95. Which of the following best describes the value of full-length mock tests, such as this one, in exam preparation?
    (a) They build exam-realistic time management and reveal specific weak areas for targeted revision (b) They have no diagnostic value whatsoever (c) They are useful only for memorising exact repeated questions (d) They should be attempted only after the actual exam
96. Which of the following best describes the general purpose of the "General Awareness" section within RRB JE CBT 2?
    (a) Assessing candidates' broad awareness of current affairs and general knowledge alongside technical competence (b) Testing only technical circuit theory (c) Serving no evaluative purpose whatsoever (d) Replacing the technical section's marks weightage entirely
97. Which of the following best summarises the overall preparation philosophy reflected across this book's mock tests?
    (a) Consistent, structured, full-syllabus practice builds both knowledge and exam-taking skill (b) A single mock test alone is sufficient for complete preparation (c) Mock tests have no bearing on actual exam performance (d) Only reading theory chapters matters
98. Which of the following best describes why RRB JE Electrical candidates should combine strong technical fundamentals with awareness of sector developments?
    (a) Both are drawn upon across the technical and general awareness sections of CBT 2 (b) Only technical fundamentals are ever relevant (c) Only sector news is ever relevant (d) Neither is relevant to actual exam content
99. Which of the following best describes an appropriate final-day-before-exam activity?
    (a) Light revision of formula capsules and quick facts, avoiding new heavy topics (b) Attempting an entirely new, unfamiliar technical subject for the first time (c) Skipping all revision entirely (d) Studying continuously through the entire night with no rest
100. As a final concluding note across this mock test series, sustained, structured practice across circuits, machines, power systems, measurements/electronics, and general awareness is:
     (a) Central to strong performance in the RRB JE Electrical Engineering CBT 2 examination (b) Irrelevant to actual exam performance (c) Useful only for the interview stage, not the written exam (d) Useful only for candidates targeting non-technical posts

Answer Key with Explanations

1.(a) Conductance is the reciprocal of resistance.

2.(a) Susceptance is the reciprocal of reactance.

3.(a) Admittance is the reciprocal of impedance.

4.(a) Power factor equals active power over apparent power.

5.(a) Maximum power transfer with reactive elements needs the complex conjugate load impedance.

6.(a) Per-unit values are ratios relative to a chosen base.

7.(a) Per-unit simplifies calculations across voltage levels via transformers.

8.(a) Single-phase supply has one live conductor (plus neutral/earth).

9.(a) A two-wire DC system has positive and negative conductors.

10.(a) Form factor is RMS over average value.

11.(a) Peak factor is peak over RMS value.

12.(a) A square wave's RMS equals its peak value.

13.(a) A balanced load draws equal current magnitude with 120-degree phase relation.

14.(a) An unbalanced load has unequal phase currents, possibly needing a neutral path.

15.(a) Neutral sizing is based on expected unbalance current.

16.(a) A parallel capacitor improves an inductive load's power factor.

17.(a) Below resonance, series RLC impedance is net capacitive.

18.(a) Above resonance, series RLC impedance is net inductive.

19.(a) Parallel resonance (anti-resonance) has impedance at or near maximum.

20.(a) Resonance underlies filter design and tuned circuits.

21.(a) DC motor mechanical power output is approximately Eb×Ia.

22.(a) Series motor torque rises roughly with current squared before saturation.

23.(a) Speed regulation relates no-load to full-load speed.

24.(a) Shunt motors have the best (most nearly constant) speed regulation.

25.(a) Yy0 is star-star with zero phase displacement.

26.(a) Dd0 is delta-delta with zero phase displacement.

27.(a) A Scott connection converts three-phase to two-phase (or vice versa).

28.(a) Inrush current is a brief high surge at initial energisation.

29.(a) Inrush current is primarily caused by core saturation during energisation.

30.(a) Unrestricted starting current is several times rated full-load current.

31.(a) DOL starting suits relatively small motors where the surge is acceptable.

32.(a) Star-delta reduces starting current/torque by roughly a factor of one-third.

33.(a) Induction motor efficiency often peaks somewhat below full rated load.

34.(a) Cogging torque is ripple from magnet-slot interaction even without current.

35.(a) Unity PF operation draws current in phase with voltage, no reactive component.

36.(a) Over-excitation drives a synchronous motor toward leading power factor.

37.(a) Under-excitation drives a synchronous motor toward lagging power factor.

38.(a) Terminal voltage tends to drop with load current for lagging (inductive) loads.

39.(a) Terminal voltage may rise with load current for sufficiently leading loads.

40.(a) This behaviour underlies reactive power control practice in real systems.

41.(a) A CVT uses a capacitive divider plus intermediate transformer, cheaper than a conventional PT.

42.(a) Current-limiting fuses interrupt high fault currents quickly, limiting peak let-through.

43.(a) Arc flash is a sudden energy release from an arc fault, posing severe injury risk.

44.(a) Arc-flash labelling helps workers select PPE and safe procedures.

45.(a) Pickup setting is the threshold at which a relay begins to operate.

46.(a) A time-current curve relates fault current magnitude to relay operating time.

47.(a) Inverse-time characteristics mean operating time decreases as current increases.

48.(a) Definite-time relays operate after a fixed delay regardless of exact current above pickup.

49.(a) Instantaneous elements operate with no intentional delay for very high currents.

50.(a) Directional protection suits systems with possible bidirectional fault current flow.

51.(a) REF protection is applied to transformers/generators for sensitive earth fault detection.

52.(a) Negative sequence protection detects unbalance that can cause overheating.

53.(a) Loss of excitation protection detects field failure causing abnormal machine behaviour.

54.(a) Reverse power protection detects the generator absorbing rather than supplying power.

55.(a) Under-voltage protection detects voltage falling below a threshold.

56.(a) Over-voltage protection detects voltage rising above a threshold.

57.(a) Differential protection offers high sensitivity/selectivity within a defined zone.

58.(a) CT accuracy/matching across the zone is a key practical limitation.

59.(a) Commissioning verifies settings, CT/PT connections, and simulated fault response.

60.(a) These protection concepts reflect real power system operation/maintenance knowledge.

61.(a) A Wien bridge oscillator generates sinusoidal signals at a specific frequency.

62.(a) A VCO's output frequency varies with an applied control voltage.

63.(a) A PLL synchronises an oscillator's phase/frequency to a reference signal.

64.(a) A microprocessor is a CPU chip typically needing external memory/peripherals.

65.(a) An embedded system is dedicated computing for specific functions within a larger device.

66.(a) An RTOS gives deterministic, timely response within specified constraints.

67.(a) Signal conditioning includes amplification, filtering, and linearisation.

68.(a) An isolation amplifier electrically isolates sensor and downstream circuitry.

69.(a) Current loop signalling (4-20mA) offers good noise immunity over long runs.

70.(a) The 4mA live zero distinguishes a genuine zero from a broken wire (0mA).

71.(a) A fieldbus enables digital communication among multiple field devices/controllers.

72.(a) Industry 4.0 integrates automation, data exchange, IoT, and smart technologies.

73.(a) A power factor meter directly measures cos φ.

74.(a) A synchroscope indicates phase relationship between two AC sources before paralleling.

75.(a) Synchronising requires matching voltage, frequency, and phase sequence/angle.

76.(a) Incorrect-phase synchronising risks damaging transient currents/mechanical stress.

77.(a) A creep test checks for unwanted meter registration with no load.

78.(a) Harmonics analysis identifies/quantifies distortion sources for corrective action.

79.(a) Active filters offer more adaptable, dynamic harmonic compensation than passive filters.

80.(a) Digital technology increasingly integrates with traditional electrical engineering principles.

81.(a) PM Surya Ghar promotes subsidised rooftop solar for households.

82.(a) India invests in grid strengthening/storage/flexible generation for renewable variability.

83.(a) Green energy open access facilitates consumer access to renewable power via the grid.

84.(a) NMEEE is a climate-action-plan mission focused on energy efficiency.

85.(a) Growing data centre demand requires careful grid capacity planning.

86.(a) 5G is the fifth-generation mobile network technology.

87.(a) A blockchain is a distributed digital ledger across multiple systems.

88.(a) Peer-to-peer energy trading is direct prosumer-consumer trading via a digital platform.

89.(a) A VPP aggregates distributed energy resources as a coordinated resource.

90.(a) Sector current affairs test awareness relevant to the recruiting organisation.

91.(a) Current affairs evolve, so recent developments are more likely freshly tested.

92.(a) A well-rounded plan mixes concept revision, formula capsules, and mock practice.

93.(a) Understanding formula rationale helps apply them correctly, avoiding errors.

94.(a) Sound strategy attempts confident/eliminable questions, cautious on pure guesses.

95.(a) Mock tests build time management and reveal weak areas.

96.(a) The GA section assesses broad awareness alongside technical competence.

97.(a) Structured, full-syllabus mock practice builds knowledge and exam skill.

98.(a) Both technical and sector-awareness knowledge are drawn upon in CBT 2.

99.(a) Light revision of capsules/facts suits the final day before the exam.

100.(a) Structured practice across all sections is central to strong CBT 2 performance.