Assistant Engineer Question Paper 2008

1) Thyrites are used for protection against
a. corona
b. surge current
c. damping
d. over current
2) The capacitance connected between the I/P and O/P of an amplifier affects its high frequency response due to
a. COLPIT effect
b. MILMAN effect
c. COLLINS effect
d. MILLER effect

3) For rural electrification in a country like India with complex network it is preferable to use
a. MOCB
b. Vacuum CB
c. Oil CB
d. Air break CB

4) Modulation is a process to vary
a. none of the these
b. Carrier signal by the signal to be transmitted
c. Signal to be transmitted
d. Signal to be transmitted as well as to vary carrier signal by the signal to be transmitted

5) The major application of Zener diode is
a. Voltage regulation
b. Chopper
c. Amplifier
d. Rectifier

6) KVL states that the algebraic sum of the voltage drop around a closed loop in an electric circuit is
a. equal to 2
b. equal to zero
c. equal to 1
d. equal to the input voltage

7) Which one of the following is not related to modems?
a. DCE
b. data phone
c. data-set
d. Telephone

8) The value of coefficient of coupling is always
a. none of the above
b. greater than 1
c. equal to 1
d. less than 1

9) The roots of the characteristic equation are called
a. Zeroes
b. Poles
c. Eigen values
d. Eigen vectors

10) Silicon devices are used for high temperature application compared to germanium because
a. silicon is more thermally stable
b. reverse saturation current is less in silicon
c. silicon can dissipate more power
d. none of the above

11) The ASCII code is
a. 9 bit code
b. 7 bit code
c. 5 bit code
d. 11 bit code

12) Star delta starter is used for starting
a. Squirrel Cage Motor with delta connected stator winding
b. DC Motor
c. Synchronous motor
d. Universal Motor

13) An automatic iron box is an example of
a. a single feedback control system
b. an open loop control system
c. none of the these
d. a multi feedback control system

14) Transmission lines are transposed to
a. reduce copper loss
b. reduce skin effect
c. prevent interference with neighbouring telephone lines
d. prevent short-circuit between any two lines

15) What is the value of modulation index in AM?
a. above 1
b. between 0 and 1
c. between -1 and 0
d. above 100

16) Steady state stability of a power system is improved by
a. decreasing generator inertia
b. reducing fault clearing time
c. using double circuit line
d. single pole switching

17) The voltage gain of an emitter follower is always
a. less than 1
b. more than 1
c. greater than or equal to 1
d. 1

18) The rms value of sine wave is
a. 0.707
b. 0
c. 0.5
d. 1

19) The most important part of an operational amplifier is
a. Adder
b. Substractor
c. Integrator
d. Differential amplifier

20) A + AB is equal to
a. A
b. A + B
c. B
d. AB

21) A cache in a computer is
a. none of the above
b. used to improve the storage capacity
c. used to hold more date
d. used to increase the speed of execution

22) In an EXCLUSIVE-OR gate, when the O/P is zero, the inputs are
a. 1,1
b. 1,0
c. 0,1
d. 1,x

23) The transfer function is defined for
a. All of the above
b. Linear and time-variant system
c. Non-linear and time-variant system
d. Linear and time-invariant system

24) Donor type impurities
a. create excess free electrons
b. have five valence electrons
c. all of the above
d. used to make n-type semiconductors

25) When the supply frequency is decreased the capacitive reactance
a. increases
b. decreases
c. remains the same
d. unpredictable

26) When resonance occurs in a circuit, the pf is
a. 1
b. greater than 1
c. 0
d. less than 1

27) A series circuit containing passive elements has the following voltage and current
v = 100 sin (314t + 50 ) and
i = 4 cos (314t + 13 ).
The circuit elements
a. could be either R and C or R, L and C
b. must be L, C and R
c. must be R and C
d. must be R and L

28) A CLASS C power amplifier is one in which the operating point is chosen such that the output current
a. always flows
b. zero for more than one half of I/P cycle
c. never flows
d. zero for less than one half of I/P cycle

29) The outstanding characteristic of a direct coupled amplifier is its
a. ability to amplify DC and low frequency signals
b. avoidance of frequency sensitive components
c. temperature stability
d. economy

30) When a 3-phase synchronous motor is running at synchronous speed, the damper winding produces
a. Torque aiding developed torque
b. Damping torque
c. Eddy current torque
d. Zero torque

31) Which one of the following is not a method of power generation?
a. Thermal
b. CHD
c. MHD
d. Hydroelectric

32) For stability and economic reasons we operate the transmission line with power angle in the range
a. 10° to 25°
b. 65° to 80°
c. 60° to 75°
d. 30° to 45°

33) Ferranti effect is experienced on long transmission lines when it is
a. lightly loaded
b. all of the above
c. on full load at 0.8 pf lag
d. on full load at upf

34) The gain of the amplifier is usually expressed in
a. Volts
b. mho
c. Amperes
d. Decibels

35) www stands for
a. World wide weight
b. Wide world weight
c. Wide world web
d. World wide web

36) A dc cumulatively compounded motor delivers rated torque at rated speed. If the series fields is short circuited then the armature current and speed will
a. increase and decrease respectively
b. both decrease
c. decrease and increase respectively
d. both increase

37) Which one of the following is a synchronous optical network ?
a. SONET
b. TELNET
c. INTERNET
d. DELNET

38) Micro-programming is a technique for
a. writing small programs
b. programming the microprocessors
c. programming the control steps of a computer
d. programming input and output

39) The number of flip flops required in a decade counter is
a. 2
b. 10
c. 3
d. 4

40) A 3-phase synchronous motor is operating at a load angle of 20° and with excitation voltage equal to the applied voltage. The synchronous reactance drop in terms of excitation voltage
a. 38.2%
b. 34.73%
c. 69.46%
d. 32.9%

41) The collector current of transistor is always
a. none of the above
b. greater than emitter current
c. less than emitter current
d. equal to emitter current

42) Base modulation is used in TV transmission because
a. Power required is small
b. All of the above
c. High degree of linearity
d. Large power O/P and better efficiency

43) A resistance is connected in series with an inductive coil. The phase difference between the current and applied voltage
a. none of the above
b. increases with increase in supply frequency
c. decreases with increase in frequency
d. remains constant

44) Rise time of an under damped system is
a. Time taken by the response to reach 50 %
b. time taken by the response time to rise from 0 to 100%
c. time taken by the response to reach 95%
d. None of the above

45) Which of the following is used for serial access storage only?
a. RAM
b. Core memory
c. Magnetic tape
d. Maganetic disk

46) Which amplifier configuration has the lowest output impedance ?
a. CO
b. CB
c. CC
d. CE

47) Superposition theorem is applicable only for circuits which are
a. Non-linear
b. Bilateral
c. Linear
d. Linear and Bilateral

48) The following protocol is used used for accessing web pages
a. SMTP
b. PTTP
c. HTTP
d. FTP

49) For a given cross-sectional area of transformer core, stepped cores are used
a. to reduce the core loss
b. to reduce the magnetizing current
c. to provide more mechanical strength to the core
d. to reduce the conductor material

50) While finding the Thevenin equivalent circuit between two terminals, Vth is equal to
a. Net voltage available in the circuit
b. emf of the battery nearest to the terminals
c. Short circuit terminal voltage
d. Open circuit terminal voltage

51) The peak overshoot of a second order system is
a. is zero
b. independent on damping ratio
c. depends on damping ratio
d. is a constant

52) Input impedance of a transmission line at any distance from the load can be determined using
a. Ben chart
b. Smith chart
c. none of the above
d. Gant chart

53) The surge impedance of 50 km long underground cable is 50 ohms. For a 25 km length it will be
a. 25
b. 100
c. 50
d. 75

54) A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. When the stator frequency is 50Hz, slip of the motor is
a. 4%
b. 2%
c. 5%
d. 2.5%

55) An ideal OP-AMP has
a. infinite bandwidth
b. all of the above
c. infinite gain
d. infinite input impedance

56) A 3-phase synchronous generator is operating at constant load while the excitation is adjusted to give unity pf current. If the excitation is now increased the pf will become
a. Unity
b. Leading
c. Lagging
d. Zero

57) The residual magnetism of a self-excited dc generator is lost. To build up its emf again
a. the field winding connection must be reversed
b. field winding should be excited by low voltage DC voltage
c. its armature connection must be reversed
d. the fieldd winding must be replace

58) A 3-phase breaker is rated at 2000 MVA, 33 kV. Its making current will be
a. 89 kA
b. 35 kA
c. 49 kA
d. 70 kA

59) While drawing the phasor diagram of a parallel circuit, which one is taken as the reference
a. Voltage
b. Current
c. Power
d. None of the above

60) The impulse ratio of a rod gap is
a. between 1.2 and 1.5
b. between 1.6 and 1.8
c. 1
d. between 2 and 2.2

61) Which one of the following is not an image file format ?
a. image.pdf
b. image.bmp
c. image.jpg
d. image.png

62) When two capacitors C1 and C2 are connected in series, the equivalent value of capacitance is
a. C1C2
b. C1C2/(C1 + C2)
c. C1 + C2
d. C1 – C2

63) How many layers are available in OSI ?
a. 4
b. 6
c. 5
d. 7

64) Which one of the following devices is not used for networking ?
a. Cub
b. Hub
c. Switch
d. Router

65) While measuring power in a three phase circuit using two wattmeters, one of the meter reads zero when
a. when the pf is 0.5
b. pf is zero
c. pf of the circuit is 1
d. pf is 0.6

66) The transfer function of a system is given by T(S) = K/[ s³(1+sT) ]. The type and the order of the system are
a. 3 and 3
b. 3 and 2
c. 3 and 4
d. 2 and 3

67) PUSH and POP operations are connected with
a. ALU
b. MEMORY
c. PROCESSOR
d. STACK

68) An instantaneous change in voltage is not possible in
a. an inductor
b. a capacitor
c. resistor
d. a current source

69) The full scale input voltage to an ADC is 10V. The resolution required is 5mV. The minimum number of bits required for ADC is
a. 11
b. 8
c. 12
d. 10

70) Which instrument is used to measure low values of resistance ?
a. Anderson Bridge
b. Wheatstone Bridge
c. Kelvin Double Bridge
d. Maxwell Bridge

71) Which of the following terms is not associated with a sample and a hold circuit?
a. Acquisition time
b. Aperture time
c. Conversion time
d. Sample mode

72) Two devices commonly used to generate light for fiber optic communication system
a. All of the above
b. LED and TFT
c. LED and ILD
d. LED and LCD

73) The form factor is the ratio of
a. rms value to average value
b. average value to rms value
c. peak value to rms value
d. peak value to average value

74) The zero point characteristics for the Potier diagram can be obtained by loading the alternator using
DC motor
Water load
Lamp load
Synchronous motor

75) The phase shift between the output and input of a CE amplifier configuration is
a. 180°
b. 270°
c. 90°
d. 360°

76) How many state equations are required to represent a system described by a third order differential equation ?
a. 3
b. 4
c. 2
d. 2

77) BJT can be used in the following mode for amplification applications
a. CC
b. CB
c. CE
d. All of the above

78) In a computer program, the process of executing the same instruction over and over is called
a. Branching
b. Circulating
c. Looping
d. None of these

79) For maximum transfer of power, internal resistance of the source should be
a. Zero
b. less than load resistance
c. more than load resistance
d. equal to the load resistance
80) The CPU of a computer consists of
a. ALU and Control Unit
b. Memory and ALU
c. INPUT and OUTPUT Unit
d. None of the above

81) The following mark up is used for creating webpages
a. PASCAL
b. HTML
c. COBOL
d. HTPP

82) The specification for a standard 74 series TTL gate reads propagation delay as 33ns and power dissipation is 1mV. This circuit is
a. Standard Schottky TTL
b. High speed TTL
c. Low speed TTL
d. Low power Schottky TTL

83) Which region of the transistor characteristic is used for amplification
a. cut off
b. active
c. saturation
d. passive

84) Power in a single phase circuit can be measured
a. using all the above 3 methods
b. using 3 volltmeters
c. using one wattmeter
d. using 3 ammeters

85) The decimal equivalent of binary 10111 is
a. 16
b. 23
c. 20
d. 4

86) Which one of the following power semiconductors can be turned on and turned off using the gate ?
a. Power transistor
b. Power MOSFET
c. SCR
d. GTO

87) For a closed loop system to be stable, the poles of the CLTF must lie
a. on the left half of the S plane
b. at the origin
c. on the right half of the S plane
d. none of the above
88) The energy stored in the magnetic field is given by
a. 1/2 LI²
b. 1/2 LV²
c. 1/2 L²V²
d. 1/2 L²I²

89) Transformer cores are laminated to reduced
a. Hysteresis loss
b. Eddy current loss
c. Both eddy current and hysteresis loss
d. Ohmic loss

90) The most commonly used detector in AM receiver is
a. Ratio detector
b. Envelope detector
c. Discriminator
d. Coherent detector

91) Three identical impedances are connected in delta to a 3-phase supply of 400 Volts. The line current is 34.65 A and the total power taken is 14.4 kW. The resistance of the load in each phase is
a. 12 ohms
b. 16 ohms
c. 10 ohms
d. 20 ohms

92) A computer can execute only programs written in
a. High level language
b. Machine language
c. Assembly language
d. None of the above

93) The insulation of modern EHV line is designed based on
a. Switching voltage
b. RI
c. Corona
d. Lightning voltage

94) An amplifier can be converted to an oscillator using
a. null feedback
b. negative feedback
c. zero feedback
d. positive feedback

95) Which amplifier configuration is used by a push-pull configuration
a. Class AB
b. Class B
c. Class C
d. Class A

96) An analog computer used for resolving a vector into two mutually perpendicular components has a device called
a. Register
b. Resolver
c. Subroutine
d. None of these

97) Main disadvantage of FM is
a. Low operating voltage
b. Complex circuits
c. Adjacent channel interferrence
d. Limited line of sight range

98) The Hall effect voltage in intrinsic silicon
a. is negative
b. is zero
c. is positive
d. changes sign on application of magnetic field

99) Which one of the following is not a power semiconductor device ?
a. GTO
b. CRS
c. IGBT
d. SCR

100) Which of the following is not a programming language ?
a. EIFFEL
b. ALGOL
c. SUSE LINUX
d. ADA

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Assistant Electrical Inspector Previous Questions Paper 2007

Assistant Electrical Inspector Previous Questions Paper 2007

1) Swinburne test can be applied only for ?

A. shunt motor
B. shunt and compund motor
C. series motor
D. series and shunt motor

2) The errors committed by a person in the measurement are ?

A. random error
B. environmental error
C. gross error
D. instrumental error

3) Which of the following is an ideal voltage source ?

A.voltage indepedent of current
B. current independent of voltage
C. voltage depends upon current
D. current depends upon voltage

4) A power MOSFET has three terminals called ?

A. collector, emitter and base
B. collector, emitter and gate
C. drain, source and gate
D. drain, source and base

5)Sine wave A has a positive going zero crossing at 30 degrees. Sine wave B has a positive going zero crossing at 45 degrees. What is the phase angle between two signals ?

A. 75 degrees
B. 15 degrees
C. 45 degrees
D. 30 degrees

6)The major cause of creeping in an energymeter is ?

A. stray magnetic field
B. over compensation of friction
C. mechanical vibration
D. excessive voltage across the potential coil

7)In a certain series RC circuits, Vr = 8V and Vi = 6 V, what is the magnitude of the total voltage ?

A. 10 V
B. 14 V
C. 8 V
D. 6 V

8) A 160 KVA and 315 KVA transformers are operated in parellel. To share the load in propotion to their ratings, their?

A. copper losses should be equal
B. impedences should be equal
C. efficiencies should be equal
D. p.u impedances should be equal

9) Which of the following theorems is applicable for both linear and non-linear circuits ?

A. none of the above
B. Thevenin’s
C. Superposition
D. Norton’s

10) The three resistance each of 9 ohms are connected in delta. The equivalent star arrangement will have each resistance values ?

A. 18 ohms
B. 3 ohms
C. 27 ohms
D. 9 ohms

11) The positive sequence component of voltage at the point of fault is zero when it is a ?

A. 3-phase fault
B. L-L fault
C. L-G fault
D. L-L fault

12) A 10KVA, 200/400V single phase transformer is supplying its rated current of 25 A. The input current is likely to be ?

A.50 A
B.more than 50 A
C.25 A
D.less than 50 A

13) The rotor power output of 3-phase induction motor is 30KW and the corresponding slip is 4%. The rotor copper loss will be ?

A.1300 W
B.1400 W
C.1250 W
D.1200 W

14) As k approaches zero the root loci approach towards ?

A.break in point
B.open loop poles
C.break away points
D.open loop zeroes

15) When an SCR is conducting, the voltage drop across it is about ?

A.50 V
B.1.5 V
C.0.1 V
D.10 V

16) In the measurement of three phase power by two-wattmeter method, if one of the wattmeter reads negative, the power factor of the load is ?

A. zero
B. unity
C. less than 0.5
D. greater than 0.5 but less than 1

17) The Bode plot approach is applicable to ?

A. any network
B. none of the above
C. non-minimum phase network
D. minimum phase network

18) A salient pole synchronous machine has maximum power output when power angle is ?

A. more than 90 degree
B. less than 90 degree
C. either 90 degree or more
D. 90 degree

19) The installed generating capacity of Idukky hydroelctric station is ?

A. 1000 MW
B. 780 MW
C. 660 MW
D. 720 MW

20) In a non-salient pole synchronous machine the distribution of field mmf around the air gap is a ?

A. sinusoidal wave
B. rectangular wave
C. flat topped stepped wave
D. stepped triangular wave

21) An induction motor takes a line current of 80A when started by direct switching. If an auto transformer with 50% tapping is used, the line current would be ?

A. 40 A
B. 80 A
C. 50 A
D. 20 A

22) Under full load condition, the power factor of rotor circuit of a 3-phase induction motor is ?

A. about 0.2 lagging
B. almost unity
C. about 0.2 leading
D. about 0.5 lagging

23) For a certain load, the true power is 100 W and the reactive power is 100 VAR. What is the apparent power ?

A. 14.14
B. 141.4 VA
C. 100 VA
D. 200 VA

24) In an induction type meter, maximum torque is produced when the phase angle between two fluxes are ?

A. 0 degree
B. 30 degrees
C. 90 degrees
D. 45 degrees

25) The diagonal elements of a nodal admittance matrix are strengthened by adding ?

A. generators
B. loads
C. shunt inductances
D. shunt capacitors
?

26) The time period of an alternating equality is 0.04 seconds. Its frequency will be ?

A. 100 Hz
B. 25 Hz
C. 50 Hz
D. 0.04 Hz

27) A single-phase fully controlled bridge rectifier is fed by a source having inductance. The output voltage during overlap period is ?

A. Vm
B. zero
C. 0.5 Vm – voltage drop across inductance
D. 0.5 Vm

28) As the temperature rises, the resistance of carbon ?

A. increases
B. decreases
C. becomes zero
D. remains unchanged

29) For an SCR dv/dt protection is achieved through the use of ?

A. R in series with SCR
B. C across SCR
C. R-C across SCR
D. R-L in series with SCR

30) The characteristics equation of a feedback control system is s(square)+ks(square)+5s+10 = 0. The value of k for the system to be critically stable is ?

A. 3
B. 4
C. 2
D. 5

31) A milli-ammeter of resistance 200 ohm connected in series with a circuit consumes 0.2 mW. If it is replaced with a milli-ammeter of 400 ohm resistance, the power consumption will be. ?

A. 1 mW
B. 0.8 mW
C. 0.4 mW
D. 0.2 mW

32) For a fixed load on the shaft, the armature current of a synchronous motor is minimum when the pf is: ?

A. leading or lagging but not unity
B. lagging
C. less than 1 and leading
D. unity

33) The presence of earth in case of overhead lines. ?

A. increses th inductace
B. increases the capacitance
C. decreases the capacitance
D. decreses the inductance

34) A voltmeter has uniform scale, it is ?

A. moving coil permanent maganet
B. moving coil dynamometer type
C. induction type
D. moving iron type

35) If an induction motor with certain ratio of rotor to stator slots runs at 1/7th of the normal speed, the motor is said to be?

A. jogging
B. cogging
C. crawling
D. hunting

36) A 4 pole dc machine has a lap winding. This winding is removed and then a wave winding with the same number of turns is put. The induced e.m.f will ?

A. increase
B. remains the same
C. may increase or decrease
D. decrease

37) The unit protection scheme provides. ?

A. remote protection
B. back up protection
C. simultaneous protection
D. primary protection

38) In an ac circuit if voltage V = (a+jb) and current i = (c+jd), then the power is given by ?

A. ac+bd
B. ac+ad
C. bc-ad
D. bc+ad

39) An auto-transformer having a transformation ratio of 0.7 supplies a load of 20 KW. The power transferred inductively from primary to secondary is ?

A. 6 KW
B. Zero
C. 20 KW
D. 14 KW

40) Megger is used for ?

A. measuring current
B. measuring power
C. measuring voltage
D. measuring insulation resistance

41) Which generators require an equilliser bar for parallel operation?

A. series and compound
B. series
C. compound
D. shunt

42) The number of disc in a string of insulators for 400 kV ac overhead line lies in the range of ?

A. 15 to 16
B. 22 to 23
C. 9 to 10
D. 32 to 33

43) A 0-100mA PMMC ammeter reads 80mA in a circuit. If its bottom control spring snaps suddenly, the meter will read nearly ?

A. 100mA
B. zero
C. 80mA
D. 20mA

44) Laplace transform of the output response of a linear system is the system transfer function when the input is ?

A. a ramp signal
B. a step signal
C. a sinusoidal signa
D. an impulse signal

45) Load flow study is carried out for ?

A. fault calculations
B. stability studies
C. system planning
D. load frequency control

46) The neutral current in a balanced three-phase four wire star connected load is ?

A. zero
B. root 3 IL
C. Iph
D. root 3 Iph

47) The form factor is the ratio of ?

A. average value to rms value
B. peak value to rms value
C. peak value to average value
D. rms value to average value

48) Ferranti effect on long overhead line is experienced when it is ?

A. on full load at 0.95 lag
B. on full load at 0.8 pf lag
C. lightly loaded
D. on full load at upf

49) A forward voltage can be applied to an SCR after its ?

A. anode voltage reduces to zero
B. gate recovery time
C. reverse recovery time
D. anode current reduces to zero

50) As the load on a synchronous motor is increases, the torque angle ?

A. remains the same
B. increases
C. decreases
D. may increase or decrease

51) A single –phase transformer is rated at 100 KVA, 5000/250V. The full load copper losses are 1KW. The load KVA for maximum efficiency is: ?

A. 141.4 KVA
B. 50 KVA
C. 100 KVA
D. 70.7 KVA

52) The usual value of slip of a 3-phase induction motor at full load is about ?

A. 0.8
B. 0.05
C. 0.1
D. 1.0

53) Hunting is prevented in a 3-phase synchronous motor by ?

A. short-pitch winding
B. compensating windings
C. dummy coils
D. damper winding

54) The span of a zero centered ammeter having a scale from -10A to +10A is ?

A. 10 A
B. 20 A
C. 0 A
D.-10 A

55) The average load factor of thermal power plants in India is ?

A. 50-60%
B. 35-40%
C. 25-30%
D. 80-95%

56) The permissible variation of frequency in power system is ?

A. + or – 1%
B. + or – 3%
C. + or – 2%
D. + or – 5%

57) Moving iron and PMMC instruments can be distinguished from each other by looking at ?

A. scale
B. scale range
C. pointer
D. terminal size

58) Determine the current if a 10 C charge passes a point in 0.1 sec ?

A. 0.01 A
B. 10 A
C. 100 A
D. 1 A

59) The practical unit of electrical is ?

A. Watt-hour
B. Kilowatt-hour
C. Joule-second
D. Watt-second

60) Sensitivity of an instrument is independent of ?

A. hysterisis or dead band
B. frequency response
C. amplitude distortion
D. all of the above

61) The characteristic equation of a system is s(square)+4.8+36 = 0. Its damping ratio is ?

A. 4.8
B. 0.13
C. 6
D. 7.5

62) A single phase cyclo-converter with center tapped input transformer requires ?

A. 8 SCR’s
B. 2 SCR’s
C. either 2 or 8 SCR’s
D. 4 SCR’s

63) A load commutated chopper circuit has ?

A. four thyristors
B. maybe equal or unequal
C. two thyristors
D. are always equal

64) Electrostatic instruments are essentially ?

A. ohmmeters
B. voltmeters
C. ammeters
D. wattmeters

65) A dc generator beyond critical resistance will generate ?

A. maximum voltage
B. maximum voltage and maximum current
C. maximum power
D. no voltage

66) An alternator is delivering its rated current at rated voltage and 0.8 pf lagging. If it is required to deliver rated current at rated voltage at 0.8 pf leading, the required excitation will be ?

A. less
B. more
C. more or less
D. the same

67) The highest transmission voltage in Kerala is ?

A. 400 kV
B. 110 kV
C. 220 kV
D. 700 kV

68) The origin for the investigation of closed loop stability in relation to Nyquist criterion is ?

A. 0-j1
B. -1+j0
C. 1+j0
D. 0+j1

69) Number of slip-rings in a 3-phase synchronous motor will be ?

A. 3 or 4
B. 2
C. 1
D. 0

70) The insulation resistance of a cable of length 20km is 1 ohm, its insulation resistance for 100 km length is?

A. 5 megaohm
B. 0.2 ohm
C. 2.5 megaohm
D. 1 megaohm

71) If the time of operation of a relay for unit TMS is 10 seconds the time of operation for 0.5 TMS will be ?

A. 10 sec
B. 5 sec
C. 15 sec
D. 20 sec

72) The dimension of power are ?

A. M(2)LT(-2)
B. M(2)L(2)t(-3)
C. ML(2)T(-3)
D. M(2)LT(-3)

73) The breadth factor of a 3-phase ac winding is about ?

A. 0.85
B. 0.96
C. 0.7
D. 0.5

74) The transfer function of a unity feedback system is 10/(s+1). For unit step input the steady state error will be ?

A. zero
B. 10
C. 1/11
D. 10/11

75) The range of a dc milli-ammeter can be extended by using a ?

A. shunt of low resistance
B. series high resistance
C. shunt of high resistance
D. series low resistance

76) The insulation of modern EHV lines is designed based on ?

A.the lighting voltage
B.the switching voltage
C.corona
D.voltage drop

77) The voltage of a particular bus can be controlled by controlling the ?

A. reactive power of the bus
B. phase angle
C. active power of the bus
D. phase angle and reactive power

78) For a matrix A= row 1 [1 4], row 2 [ -2 -5], the eigen values are ?

A. -2,-4
B. -1,-2
C. -1,-4
D. -1,-3

79) A digital voltmeter measures ?

A. average value
B. peak value
C. rms value
D. peak to peak value

80) A 100V voltmeter has an accuracy of 5% on full scale. The percentage error while measuring 50 V will be ?

A. 7.5%
B. 2.5%
C. 5%
D. 10%

81) A three-phase 100 KVA transformer is composed of three seperate transformers connected in delta-delta. If one of the units get damaged and it is operated in open delta; the rating will be:?

A. 50 KVA
B. 86.6 KVA
C. 57.7 KVA
D. 100 KVA

82) The rectifier type instrument is not free from ?

A. temperature error
B. frequency error
C. wave shape error
D. all of the above

83) Integrating meters are used for the measurement of ?

A. voltage
B. energy
C. current
D. phase

84) For a synchronous phase modifier the load angle is ?

A. 0 degree
B. 95 degrees
C. 30 degrees
D. 60 degrees

85) In case of a 3-phase short circuit in a system, the power fed into thr system is ?

A. active and reactive both equal
B. mostly reactive
C. mostly active
D. reactive only

86) Clamp-on-ammeter is used for measurement of ?

A. small direct current
B. large direct current
c. large alternating current
D. small-alternating currents

87) Graphite is used in nuclear power plants as a ?

A. electrode
B. moderator
C. coolant
D. fuel

88) A square wave type voltage of peak magnitude 200 V is measured by a moving iron voltmeter. It will read ?

A. 400 V
B. 100 V
C. 600 V
D. 200 V

89) The impedance value of a generator is 0.3pu on a base value of 22kV, 150MVA. The impedance value for a base value of 11kV, 50 MVA is ?

A. 0.4pu
B. 0.15pu
D. 0.6pu
E. 0.3pu

90) In a dc machine, the coil span ?

A. must be equal to pole-pitch
B. can never be equal to pole-pitch
C. may or may not be equal to pole pitch
D. is equal to half pole-pitch

91) The convergence characteristics of the Newton-Ralphson method for solving a load for problem is ?

A. quadratic
B. linear
C. cubic
D. geometric

92) A single –phase transformer is rated at 100 KVA, 5000/250V. The full load copper losses are 1KW. The load KVA for maximum efficiency is: ?

A. 141.4 KVA
B. 50 KVA
C. 100 KVA
D. 70.7 KVA

93) A transformer can have zero regulation at ?

A. lagging pf
B. leading pf
C. zero pf
D. unity pf

94) In a single-phase semi converter, for continuous conduction free wheeling diode conducts for ?

A. pi
B. firing angle alpha
C. alpha + pi
D. pi – alpha

95) The resistance of a parallel circuit consisting of two resistors is 6 ohms. When one of the resistors is removed the effective resistance becomes 9 ohms. The resistance of the removed wire is ?

A. 18 ohms
B. 3 ohms
C. 15 ohms
D. 12 ohms

96) A fault is more severe from the view point of RRRV if it a ?

A. long line fault
B. either long line or medium length line fault
C. short line fault
D. medium length line fault

97) The cheapest instrument for dc measurement is ?

A. PMMC
B. moving iron
C. electro-dynamic
D. hot wire

98) The location of the closed loop conjugate pair of pole on jw axis indicates the system is ?

A. unstable
B. stable
C. marginally stable
D. critically stable

99) McMurray full bridge inverter uses ?

A. none of the above
B. complementary communication
C. natural communication
D. auxilliary communication

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