Technical Portion: NPGCL Test 1
Technical Portion: NPGCL Test 1
Technical Portion: NPGCL Test 1
SHAAN
Technical Portion
NPGCL TEST 1
1. Vertex is also called=Node
2. When the current in the light bulb decreases by 2%, its power decreases by =4%
3. What is transformer part Primary coil, secondary coil & = Core
4. Electric lines of force about negative point charge are =radial inwards
5. Which is Semiconductor Switch = Thyristor
6. How thyrister is turned off= Forced Commutation
7. Protection relay used are? (OR) There are two types of overload protection?
Instantaneous over current and Time over current
8. Current transformer is used with Protection device for measuring = Current
9. Which is not Part of Steam Turbine? Moderator, Economizer, Precipitator
10. Diode Operation voltage = 0-0.7v
11. Power Plants run on Natural Gas, Steam coal, etc are =Fossil Fuel Plants
12. Which Plant do not used Heat Exchangers or turbines= Geothermal
13. Steam power plant flow chart or something how many steps=4
14. In a generator of 60 HZ and 10 Pole what will be N Speed = 120*60/10=720
15. In a Substation where no transformer is? Switching Substation
16. High frequency application we use? Air core Transformer
17. Sin wave is characterized by? Amplitude, Frequency & Phase
18. Dynamic Disturbance Recorders (DDRs), which record incidents that portray power system
behavior during dynamic events such as low-frequency = (0.1 Hz - 3 Hz) oscillations and
abnormal frequency or voltage excursions
19. Induction motor rotor are Squirrel cage and Wound type = Squirrel Cage (Both)
20. A sinosoidol is represented by = Phasor
21. If there are less than 4 free electron then its =Conductor
22. Which is Not a substation = Line Substation
23. Which is not at type of thyristor? = inverter Grade
24. Efficiency of thermal plant =33-48%
25. What is basic principle behind motor operation? = electromagnetism
26. Induction motor is similar to = asynchronous
27. SEIMENS is unit of = Conductance
28. System protection devices which includes? A)Reliability, B) selectivity, C) cost, D) Speed,
E) Simplicity (ALL)
29. 2 types of Exciters? 1. Rotating 2. Static
30. Which transformer is used in arc welding???? Leakage
31. When admittance increases current increases or Decrease? Increase
32. Power switch is characterized into how many groups? 3 (uncontrolled, semi controlled,
controlled)
33. Stator core is made of many thin metal sheets called? lamination
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34. Most squirrel cage rotor is made by die casting of? Aluminum conductor bars
35. All process system consists of three main factor or term? manipulated Variable, controlled
variable and uncontrolled (disturbances)
36. Substation transforms voltage from high to low And reverse and perform many of the several
important functions
37. The input for a distribution substation is typically at least two transmission or sub transmission
lines
38. Generators are cooled by? Air-water cooled Fins
39. A process control system consists of process, measurement control: = Analysis
40. Generator voltage is determined from excitation is? island operation
41. The matrix obtained by deleting the column corresponding to the reference node in the element
node incidence matrix A is called bus incidence matrix A
42. Stainer is used to prevent foreign particles to reach turbine along with steam.
43. __________is used for emergency stop of steam along? throttle valve
44. Complex quantities in power system are represented by? Phasor
45. When a small resistance or impedance is accidentally or intentionally inserted b/w two points of
different potential, it is called short circuit
46. The loss in a T/F due to reversal of direction of current is called? Hysteresis loss
47. The frequency of generator depends on? speed and no of poles
48. Higher efficiency can be obtained at higher temperature, this is dictated by? Carnot efficiency
49. The boiler in which tubes are placed in a horizontal cylinder is called? horizontal, fin tube
50. Reactive power at load determine by.......? field current heating
51. Magnetic density circuit is increased by? increasing no of turns
52. A circuit breaker which can be separated from the circuit without interruption in the circuit
because of additional contacts is called? (Removable/ Separable CB/ Disconnector)
53. The study of disturbances on power system during abnormal operating conditions is called?
Steady State Analysis ( OR )
Which analysis deals with the effect of disturbances on power system?
a) Fault trend analysis, b) sinusoidal analysis c) stability analysis d) line power analysis e) Load
flow analysis
54. Equipment with capacity to work within range? circuit breaker making capacity
55. Sinusoidal voltage and current at constant frequency is characterized by 2 parameters, a max
value and --------? a) angle (phase angle) b) value of load angle c) R value d) load angle
56. Which one is not a transformer? 1) Laminated 2) resonance 3) single instrument transformer 4)
ferrite circuit transformer 5) caste iron transformer.
57. Synchronous generators are used, because they offer precise control of voltage, frequency,
VARS , watts.
58. The sensitivity of measurement is a measure of the change in the instrument output, which
occurs when the quantity being measured changes by a given amount.
59. Voltage Regulation in generation voltage?
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60. Intercepting contacts of circuit breaker is a set of contacts which enable circuit breaker to be
removed? a) Withdrawal b) discontinue c) plug in d) current limiting e) Moulded case
NPGCL TEST 2
1. CB is similar to Common gate of FET
2. Low resistance measuring device is Kelvin Bridge.
3. The shunt winding of motor has a resistance of 85 ohm at 22 degree when the motor runs at full
load, its resistance increases to 100 ohm. The resistance temperature coefficient of winding per
0 degree is 0.004. The rising temperature of winding will be? Answer is 70 degree.
4. A 100V bulb has a resistance of 500 ohm. The number of hours it can work per every KWh of
energy consumed will be? 50 hours.
5. Main feature of crystal oscillator is stability.
6. In class A, conduction angle is 360 degree.
7. For pre amplification, which Power amplifiers are used for linearity purpose? (Every pre
amplifier in system is ___________ amplifier to achieve high linearity)? Class A, Class B, Class C,
Class A-B.
8. In metals, electrons revolve because of? OR Motion of electrons in conductor? a) constant V,
sinusoidal, square, triangular, non periodic
9. Which current flows due to minority charge carriers? Hole current, reverse leakage current,
forward leakage current, all of the above
10. Moderator used in Nuclear is Graphite.
11. In alternator, if power factor load is unity, then armature flux will be? Cross magnetizing,
demagnetizing, reduce to zero, square waveform
12. State variables are used in which models? All of above.
13. LTI system can be completely recognized by impulse response of the system. (Impulse, Step,
ramp)
14. Stray Voltage is small voltage (less than 10) which can be measured between two points.
15. Stepper motor, speed depends upon frequency.
16. In motor which O.L protection is used? Thermal O.L relay.
17. Vrms*Irms=Apparent Power
18. Power against Inductance is reactive power.
19. Power against resistance is active power. (Power which is actually dissipated in circuit resistance
is called active power)
20. If all conductors are grounded to the same grounding system, what is the probability of shock?
Minimum
21. CMMR = Differential Gain to Common Mode
22. CMMR should be (low, maximum, high, and zero) for better OPAM operation.
23. Uranium-235 is an isotope of uranium making up about 0.72% of natural uranium
24. Thermal to K.E is converted in the Rocket.
25. Moving iron type Ammeter has few turns of thick wire so that its resistance is less.
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26. The advantage of permanent magnet ammeter is all of above. (Effective eddy current damping,
low hysteresis loss, low power consumption, uniform scale, very sensitive to current.)
27. If height of transmission tower is increased, Capacitance will decrease and inductance remains
same.
28. For current amplification, CC is used.
29. VI characteristics of UJT are similar to?
(a) CE with linear & saturation region, (b) FET with linear & pinch off, (c) Tunnel diode
(d) Pn-junction diode
30. TRIAC is bidirectional device.
31. Solid grounding is used below 660V. (above 220 kV, above 11 kV, below 660 V, below 115 V)
32. In submarine power is transmitter through which cables: HVDC
33. In which power plant availability of power is least reliable? Wind
34. High gain DC-DC convertor used in which system? All of above, Solar system, Battery backup
35. Which principle is used to analyzing the fault? (Thevenine, norton, Superposition, Jordon).
36. Q-point operating point of transistor model analysis.
37. Negative resistance is of Tunnel diode.
38. Inverse/Opposite of power factor is Q factor.
39. Roll off rate of operational amplifier is usually is -20 dB decades.
40. Channel is in b/w Drain and Source of JFET.
41. Transformer rating is given in KVA instead of KW why? (Customary, loss depends upon V&I,
power factor is not known, All of above).
42. In Transformer ratio 20:1 means 20 number of primary turns to 1 secondary coil turns
43. Stator appears to be stationary and rotor freely moves which is rotating transformer is
equivalent to induction motor.
44. Transformer has maximum efficiency when Cu losses become equal to Fe losses.
45. SCR goes into saturation when? gate to cathode voltage forward biased
46. CE amplifies (V, I, P, all of above)
47. DC motor has high torque.
48. Accumulative motor adds up the series and shunt magneto motive force.
49. Control system is used for? (We built control systems for _______?)
a) Remote control, b) power application, c) disturbance control, d) all of above
50. OPAM optimum operating voltages are ( +_18, +_15, etc)
51. LC Tuned oscillator stability is dependent upon (Q factor, L, C, transistor).
52. Light is produced in electric discharge lamp due to (heating effect, magnetic effect, ionization in
a gas / vapor).
53. What is produced by superconductor (V, temp, Press, magnetic field)
54. In superconductors what happens ( repulsion of magnetic, absorbing of magnetic field,
absorbing of electric field, repulsion of electric field)
55. Which engine has highest air fuel ratio? Gas Turbine, Petrol, Gas ,Diesel, Hydro turbine
56. Diode is used for rectification.(or Device that converts ac into dc)
57. Diode limiters are used for limiting positive and negative cycles both.
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MEPCO TEST
1. Power factor? Answer: true power/apparent power
2. To reduce cost of power generation? Answer: Load factor (higher/increase) +Diversity factor
(higher increase)
3. An Ideal voltage source has internal resistance? Answer: 0 Resistance
4. An Ideal current source has internal resistance? Answer: Resistance
5. ____ is defined as the measure of instrument by which it is error free
A) Accuracy, B) Precision, C) Resolution
6. Electrical lines of force about a negative charge are
A. Circular, anticlockwise, B. Circular, clockwise, C. Radial, inward, D. Radial, out ward
7. A _____ meter is used a null detector in Wheatstone bridge
A) Ammeter, B) Voltmeter, C) Galvanometer
8. A moving iron ammeter coil has few turns of thick wire in order to have:
A) Low resistance, B) High sensitivity, C) Effective damping, D) Large scale
9. A permanent magnet coil meter has which features?
A) Low power consumption, B) No hysteresis loss, C) reduced eddy current
D) reduced damping, E) all
10. A digital signal is what in? A) Discrete, B) Discrete in time, C) Discrete in amplitude
D) Discrete in neither time nor amplitude, E) Discrete in both amplitude and time
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11. The EM field and current are concentrated close to the surface of the conductor. The
phenomenon is called? Answer: Skin Effect
12. The wavelength of an EM wave after reflection at an angle on a surface
Answer: Increases in the actual direction of propagation
13. When electric field is parallel to the plane of incidence, the electromagnetic wave is said to be
Answer: Parallel polarized
14. x H = J + D is Maxwell equation
15. Buchholz relay is used in Transformer Protection
16. Gates between following range referred by MSI
17. The MSI (Medium Scale Integration) technique, the number of transistors on the single IC
package can be fabricated are? a) less than 10, b) 10 to 100, c) 100 to 1000, d) 1000 to 10000
18. Gates between following range referred by LSI
19. The LSI (Large Scale Integration) technique, the numbers of transistors which can be fabricated
on the single IC are? a) 10 to 100, b) 1000 to 10000, c) 100 to 1000, d) greater than 10000
20. Which type of system is referred by pneumatic system? A) Pressure, B) Hydraulic, C) Fluid
21. Cross over distortion is? Answer: Class B
22. Due to velocity saturation, MOSFET reaches saturation? A)Before Pinch off, b) After pinch off,
c) At Q point, d) Before Q point, e) After Q point
23. If ROC (Region of Convergence) does not lie inside unit circle then?
a) Fourier transform converges, b) Z-transform converges, c) Harley transform converges
d) Does not converges
24. Transfer function is? A) Mathematical model, B) System with no physical structure,
C) Can be calculated through differential equations
25. Which of the following statement is correct about continuous & discrete LTI system:
a) convolution sum is approximation of convolution integral
b) convolution integral is approximation of convolution sum
c) Both are explicit realization, d) all of the above
26. LTI system is stable when? a) Zero is inside a unit circle, b) Poles and Zero are inside a unit circle
c) Zero at origin, d) Poles at origin. (For a LTI system if all the zeroes and poles are inside the unit
circle then? System is stable)
27. Which bulb operates on lowest power? A. Night bulb, B. Neon bulb, C. GLS bulb, D. Torch lamp
28. If R1 is the resistance of a coil of copper at t oC and RT is the resistance at T oC and also the
resistance temperature coefficient of copper per degree centigrade at 0oC is 1/234.45, then
Rt/RT
(A) (1+t) / (1+T)
(B) (1+ 234.45t) / (1+234.45 T)
(C) (234.45 + t) / (234.45 + T)
(D) (234.45 + t2 ) / (234.45 + T 2)
29. If Z transform lies in ROC then? A) System is stable; B) Inverse of system is stable
C) Both system and its inverse are unstable, D) Both system and its inverse are stable
30. Superposition theorem relates to? Linear Network
31. Kilowatt hour is the unit of? Answer: Energy
32. In Z transform cos pi/4 is the period is equal to? N=8
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33. What will be the sampling frequency that reveals the same sampled signal? (sampling freq
should b double the real signal) a. double the max period b. equal to the max period
c. greater than the max period d. half the max period
34. Which transistors are used in TTL (Transistor - Transistor Logic)? Bipolar
35. Resolution of ADC is defined as the no of bits in? Answer: Output
36. Horizontal line in the s plane is represents? Constant Peak Time and that of vertical line
represents Constant Settling time.
37. Recharge able batteries are called? Secondary batteries
38. The batteries which are charged and discharged continuously? Secondary batteries
39. Which system needs more stability? Automatic washing machine, Traffic signal system, Home
heating system, Motor with position control (a,b,c are examples of open loop systems)
40. Natural frequency in the control system represents? a) nature of transient, b) overshoot
c) oscillation, d) speed of response (Natural frequency is the frequency at which the system
would oscillate if the damping factor were zero)
41. Hay Bridge is used for the measurement of? Answer: Inductance
42. ____ Bridge used for the measurement of resistance? Answer: Wheatstone bridge
43. _____ Acts as voltage controlled variable capacitor? Answer: Varactor
44. By which a meter after checking with no current returns to its previous state? Answer:
Controlling Torque
45. By connecting a shunt of higher value in ammeter what will decrease? Answer: Current
sensitivity decreases
46. Amperes law is comparable to ________ in electrostatics? Biotsewart law, gausses law,
faradays law, Lenzs law
47. The internal part of machine is protected from environment by? (A) Housing (B) casing (C) frame
(D) enclosure
48. To decrease the power in control system we use? A) Open loop, b) Close loop
c) Combination of the these two with active elements
d) Combination of the these two with passive elements
49. Continuous signal in the time domain in frequency domain?
50. Which statement is false for switching regulators?
PESCO TEST
1. Mathematical equation that allows us to predict the value of dependent variable from known
values of one or more independent variable is called?
a) Correlation equation, b) distributive equation, c) Variance equation, d) Regression equation
e) Prediction equation
2. Z transform is used when signal is not?
a) Absolute sum able b) square sum able c) converge d) diverges e) a, b, c
3. Any constant of t domain is a impulse in f domain with
a) Infinite height, infinite width, infinite area, b) Infinite height, infinite width, unit area
c) Infinite height, zero width, infinite area, d) Infinite height, zero width, unit area
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FESCO TEST
1. Which is not the basic part of T/F? A) Corey B)Primary Winding C) Secondary winding D) Mutual
Flux
2. Fourier series representation of continuous signal require ___________ no: of harmonically
complex exponents: (Period of infinite continuous fourier series)? a) N b) n+N c) 1 d) Infinite
d) 2*pi/n
3. In 8085............is a part of control unit? A) ROM. B) Instruction registers. C) Ram. D) Op-code
4. Oscillator whose frequency can be changed by variable DC control voltage?
a) Triangular wave oscillator, b) Wien bridge oscillator, c) Crystal oscillator, d) Voltage controlled
oscillator
5. Circuit produce output wave form without external signal source? a) Filter, b) Amplifier
c) Oscillator, d) None
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WASA TEST
1. Loss that occurs in magnetic core of a transformer is? a) Copper loss b) iron loss c) Stray loss D)
Dielectric loss
2. A Circuit of zero lagging Power factor behaves as? a) An inductive circuit b) A capacitive circuit
c) R-L circuit d) R-C circuit
3. Which among the following happens in a low power factor?
A) Large kVA rating of the equipment, b) Greater conductor size, C) Reduced handling capacity
of the system, D) All of the above
4. What is the main disadvantage of phase advancers?
A) Cannot be used for motors below 200 H.P, B) Produces noise C) Can be used where
synchronous motor is un admissible, D) None of these
5. The most suitable location for the power factor improvement device is? a) Near the electrical
appliance which is responsible for the poor power factor, b) At the sending end c) At the
receiving end in case of transmission lines, d) Both (a) and (c)
6. Under what condition is D.C supply applied safely to the primary of a transformer?
a) We can connect directly to DC, b) No condition required we cant connect to DC Supply,
c) A High resistance should be connect in series with primary, but circuit will be useless,
d)The above statement is wrong
7. When the power factor in the transmission line is leading, which device is employed at
substation to reduce the power factor? a) CVT b) Reactor c) Synchronous condenser d) None of
the above
8. In a Transformer, The primary flux is always _________ the secondary
a) Greater than, b) Smaller then, c) Equal, d) Equal in both step up and Step down Transformer
9. Breaking capacity of a circuit breaker is usually expressed in terms of(A) Amperes(B) Volts(C)
MW (D) MVA
10. The fuse current in amperes is related with fuse wire diameter D as?
(A) I I/D (B) I D (C) I D3/2 (D) I D2
11. For motor circuit breakers, the time of closing the cycle is?
(A) 0.001 sec, (B) 0.01 sec, (C) 0.10 sec, (D) 0.003 sec
12. In modem EHV circuit breakers, the operating time between instant of receiving trip signal and
final contact separation is, of the order of(A) 0.001 sec(B) 0.015 sec(C) 0.003 sec (D) 0.03 sec
13. The normal frequency rms voltage that appears across the breaker poles after final arc
extinction has occurred, is?
(A) Recovery voltage, (B) re striking voltage, (C) supply voltage, (D) peak voltage
14. The number of cycles in which a high speed circuit breaker can complete its operation is?
(A) 3 to 8, (B) 10 to 18, (C) 20 to 30, (D) 40 to 50
15. In a circuit breaker the current which exists at the instant of contact separation is known as?
(A) Re striking current (B) surge current (C) breaking current (D) recovery current
16. For a high speed circuit breaker the total clearing time is nearly?
(A) 1 to 2 cycles (B) 5 to 10 cycles(C) 10 to 15 cycles (D) Less than 50 cycles
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17. The most common method of cooling employed in power transformer is?
a) Oil natural b) Natural cooling c) Air cooling d) Air-blast cooling
18. The value of flux in the emf equation of a transformer is?
(a) rms, (b) Average, (c) Maximum, (d) Integral wave cycle
19. In Three Phase Transformer, The load Current is 139.1A, and Secondary Voltage is 415V. The
Rating of the Transformer would be __________? (a) 50kVA (b) 57.72kVA (c) 100kVA (d)173kVA
20. The friction losses in Real Transformers are _________? 0% 5% 25% 50%
21. TO reduce cost we must? Increase KVA
22. KVAR is equal to? Reactive power
23. Power factor of Alternator? depends on load
24. Power factor of transformer? depends on load
25. Sound of transformer is due to? Vibration in lamination
26. Which winding will have smaller cross sectional area? HV side
27. The Resistance between primary and secondary of transformer should be? Infinite
28. The voltage at no load leads the Current by? 90 degree, less than 90
29. Voltage lags behind the current when load is connected to the transformer by what degrees? 90
30. Laminations are done to reduce? the eddy current losses
31. Fuse protection is used for current ratings up to? (A) 10 A(B) 20 A(C) 50 A (D) 100 A
32. Admittance is? Reciprocal of impedance
33. CB without resistance? SF6
34. If a conductor is passing through a metallic case with ground potential which kind of protection
is provided?
NTDC TEST
1. What is the zero sequence current if fault current is 90A? 30A
2. Increase directivity of antenna depends on? a) high gain high bandwidth, b)low gain low
bandwidth, c) high gain low bandwidth, d) low gain high bandwidth
3. AMPS uses? FM, FSK, PSK
4. GSM uses? TDMA, FDMA
5. Which modulation has higher data rates? FM, AM, QAM, QPSK
6. Fly back converter for? dc/dc, ac/dc, dc/ac, ac/ac conversion
7. Series capacitance in transmission line for? steady state stability, protection
8. In a transfer function k=0 root loci roots are? poles of open loop transfer function
9. For System stability roots must be __? right half of s plane, left half of s plane, jw axis
10. The maximum loads attached to a device called? fan in, fan out
11. Calculate voltage of toaster with joules=7500, i=13.64A, t=5, v? 110Volt
12. TCP/IP address 32 bits
13. Multiply two 16 bit numbers result is 4 bytes
14. Fault current 1500A zero sequence current 500A
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15. Induction motor torque? proportional to slip, inversely to slip, square of slip current,
16. Primary and secondary voltages in transformer are in 180 out of phase
17. Laplace transform of unit step function 1/s
18. For 8 pole generator how much Hz responds to one revolution? 4Hz
19. Why hollow conductors are used in transmission line
Reduction of the corona
20. What limits design of long transmission line thermal considerations/conductor area
21. How load is modeled in load flow analysis? A) Constant power, b) Constant impedance, c)
constant load, d) variable load
22. Orthogonal means two line perpendicular to each other?
23. Large phase mercury rectifier advantage?
24. shunt reactors used for limit short circuit current
25. TDMA uses?
26. Output occurring due to only input with zero initial conditions called?
27. Differential amplifier amplifies?
28. Link layer design also called?
29. Differential amplifier coupling transistors coupling?
30. 2 BJTs replaced with Darlington pair what happens?
31. Waves reach at the antenna which? a) modulated digital, b)modulated analog, c) aligned waves
32. Dc motor pole tip chamfered to reduce armature reaction effect
33. Definition of Electrical flux density, magnetic flux density, magnetic induction
34. Why Impedance matching performed for signal transferring? to reduce noise, reduce
attenuation,
35. At no load losses occurring in transformer are due to?
36. At no load transformer the applied voltage _ leads by 90/lags by 90/lags somewhat by 90 to
current
37. Waves reach at antenna? a) modulated digital, b) modulated analog, c) aligned waves
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7. By increasing frequency the current in series resonance circuit before Answer: increase before
resonant and after resonance decreases
8. A steam power generation has an overall efficiency of 20 %. 0.6 Kg of coal is burnt per kWh of
electrical energy generated. Calculated the calorific value of fuel? Answer: 7166.67 kCal/kg
9. If a fault occurs on any feeder, the fault current is Answer: much lower than with Un-sectional
bus bar.
10. Half wave rectifier ripple factor 1.21
11. In case of photo conductor for Germanium when forbidden energy gap is 0.72 eV, the critical
wavelength for intrinsic excitation will be Answer: 1.73 um
12. Electrical field intensity on equi-potential surface is Answer: Perpendicular to surface
13. 3.5 A and 0.031kohm heat dissipated 379.5 watt
14. What will be the thermal efficiency of a 240 V, 1000 W electric kettle if it brings 2 liters of water
at 15 C to boiling point 15 Minutes? A. 74.56 %.B. 78.96 %.C. 79.33 %.D. 80.25 %.
15. Mechanical energy is supplied to a DC generator at the rate of 4200 J / S. The generator delivers
32.2 Amp at 120 V. How much energy is cost per minute of operation? A. 20060 J.B. 20160 J.C.
23060 J.D. 25060 J.
16. Norton equivalent current is Answer: short circuit current through load
17. What is Collector current? A. Drift current B. Diffusion current C. Base current
18. The sequence components of the fault current are as follows: Ipositive = j1.5 pu, Inegative =
j0.5 pu, Izero = j pu Which fault is this? Answer: LLG
19. An overhead line conductor has an inductance per unit length of L Henry. If the entire medium
around the conductor is filled with a dielectric material of permittivity ( ), then the inductance
will be Answer: L/ 20. 650-33kV clearance between track and lowest conductor Answer: 6.1m
20. The only place where slip ring induction motors used in thermal power plants is Answer: Coal
handling plant
21. Which equipment does not supply reactive power in HVDC converter stations? Answer: Series
Capacitors
LESCO TEST
1. Probability of number two rolling dice is? 1/6
2. The function having infinite value?
a) open, b) close, c) dependant, d) independent
3. In Close loop control system, feedback strategy is term related to?
A) Input dependent, B) Fail safe, C) Error driven, D) both A & B, E) None
4. Output of open loop system is? a) O/P dependent b) O/P independent
5. In an induction motor when air gap is increased then magnetizing current increases while short
circuit current will
a) Decrease, b) Increase, c) Initially increase then stabilized, d) Initially decreased then stabilized
e) Remains unchanged
6. Optical device used to measure refraction & Ocular Focus?
a) drum meter, b) durameter, c) Dioptometer , d) declipmeter
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20. For Transmission line 300km, we have to decrease cost of conductor is reduce by 25% of the
originally set cost, so a design engineer what would you suggests? A) Voltage will be half, B)
Current will be double, C) Voltage will be double, 4) No change
21. y' + 2x = 4 (x+1)^2 is differential equation in which order?
a) First order, b) 2nd order, C) Quadratic
22. Which of the following equation shows d (function)^2/dx^2 = 1/k * d(function)/dt
a) Parabolic, b) Elliptical, c) Telegraphy, d) Laplace
23. Inductors in series 10mH, 20mH, 25mH, 5mH, net Inductance will be?
A) 15, B) 60, C) 3.4, D) 3.808
24. Inductors in parallel 10mH, 20mH, 25mH, 5mH, net Inductance will be?
A) 15, B) 60, C) 3.4, D) 3.808
25. Intel MCS-51 is commonly referred as? a. 8051, b. 8056, c. 9051, d. 5050
26. Vs = Ns d (phi)/dt? a) Lenzs Law, b) Faradays Law, c) Columbs Law
27. Partial derivative of fxy and fyx are called? a. Proper derivative, b. Improper derivative, c. Mixed
derivative, d. Universal derivative
28. _______ of fxy and fyx are simultaneous? A) Mixed derivative? B) Derivative, C) Integral,
29. Superposition theorem can be used to convert equivalent to? a) Norton, b) Thevenine, C) Both
d) None
30. Transmission voltage for 25-30 km line? A) 11kV, B) 33kV, C) 250, D) 500
31. The equation t= dq/dt represent? A. Current, B. Charge , C. Voltage
32. Transformer is designed so as there is .........leakage induction? A. High, B. Low, C. Zero
33. To turn off thyristor? A) Make gate current less than holding current; B) apply negative current
at gate
34. Using ohms law, voltage source with resistance in series is replaced by current source with
resistance in parallel? a) Voltage transformation, b) Current transformation, c) Source
transformation, d) Resistance transformation
35. Phasor diagram gives magnitude and? Phase angle
36. Required pressure of air in air blast circuit breaker?
a) 2 - 3 kg/cm2, b) 20 - 30 kg/cm2, c)200 - 300 kg/cm2, d) 2000 -3000kg/cm2
37. If scaling (Sampling) and time shifting is applied on a same signal, what should be the order of
operation? A) 1st shift then scaling (Sampling), B) 1st scaling (Sampling) then shift, C) both can
be performed in any order, D) one by one in any order, E) only 1 operation can be performed
38. Program Counter (PC) is used for? Holds the address of the next instruction to execute
39. Shunt generator has shunt winding in parallel with armature winding. The advantage is:
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A. single excitation source is required (one exciter), b. no source needed for excitation (no
exciter)
40. For input function of 2 Boolean variables there are ______ Boolean algebra functions?
a) 16, b) 8, c) 4, d) 2
41. Actual speed of synchronous generator is? Equal to rotating magnetic field
42. KCL? a) Current entering and leaving is zero, b) Negative, C) positive
43. In Oscilloscope, vertical axis represents volt/division and horizontal axis represents? Time/
division
44. Nuclear power plant use uranium annually in tons?
a) 5-10 b)10-15 ton, c)20-30 ton, d) 30-35 ton, e) 40-45ton
45. Plant has maximum load of 325MW, capacity of plant is 350MW, average peak load is 250MW,
and load capacitive factor is 0.65. Load factor is? A) 0.8, B.) 0.67, C) 0.5
46. Coal power plant uses million of tons of coal, while nuclear power plant uses only_____ ton of
uranium? A) 10-15, B) 15-20, C) 20-25, D) 30-35
47. Language used in house wiring automatic control is? A) C++ , B) Assembly, C) Ladder logic, basic,
D) Fortran
48. Relationship b/w eddy current and lamination thickness in dc generator?
A) Direct, B) Inverse, C) Square, D) depend on thrice power
49. If a path is divided to small displacements then which is correct (sum of displacement is equal
to)? a) work done is obtained by combining them, b) a single vector represent starting from
first displacement point and to the last displacement.(equivalent displacement vector)
50. Find Plasma Frequency? Data: mass of electron, Avogadros Number,
1) 2.6e15, 2) 2.6 e12, 3) 2.6e10, 4) 2.6 K, 5) 2.6
51. To obtain multi video channel in digital modulation we use ______ diode? OR (For multiple
video channels digital modulation and ____ diode are necessary?)
a) Zener, b) Schottky, c) Laser diode, d) Photo Diode
52. Baseband analog intensity modulation is done by modulating _______ applied to LED?
a. voltage, b. current, c. frequency, d. amplitude
53. The Stability of dynamic system having no input is called / described with? Lyapunov Stability
54. Which of the following statement is correct?
A) Slip ring is used in ac while commutator is used in dc
B) Commutator is used in ac and slip ring is used in dc
C) Commutator is used in both
55. In 8086, whole instruction is read when first byte is stored at?
a) Odd address, b) Even address, c)H0521, d) Anywhere, e) 0911A
56. The fault shown in circuit is known as?
A) Symmetric, B) Asymmetric, C) Skewed, D) Loplified
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64. Between two grid stations in order to decrease impedance and to have X=(3R)1/3
(A) Reduce transient (B) Reduce Line losses, (C) Steady state stability
65. Cylinder was given in figure and finds the equation of flow rate qi?
A) qi = Adh/dt, B) qi = A*dh/dt, C) dA/dt
66. If power plant fails to give power to particular area due to large load, it is referring to?
a) load shedding
67. In a time duration that condition in which system will not b able to supply power? (The
probability during at any given in a time duration wide power sources will fall show of)
a) Expected unnerved energy, b) outage frequency outrange duration (OFOD), c) off-load,
d) Loss of load probability (LOLP), e) LOLE
68. Ratio of magnetic flux density to field in vacuum? A) Relative permeability
69. First generation of computers use? A) Vacuum tubes, B) Transistor
70. When any conductor is placed in magnetic field it is subjected to Lorentz force which is?
a) Parallel to field, b) Perpendicular to field, c) 45 degree to field, d) at other some angle
71. When surface charge density is zero then normal components of_____ is continuous?
a) Electric flux density, b) Electromotive force, c) mmf
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