TS ECET EEE 2018

1. If two voltages sources v1 and v2 are connected in parallel and series respectively, find the correct relation

A. v1=v2; v1-v2
B. v1=v2; v1+v2
C. v1>v2; v1+v2
D. v1-v2; v1+v2

Answer : B. v1=v2; v1+v2
Explanation:-

2. Kirchoffs current law is the conversion of

A. energy
B. charge
C. torque
D. power

Answer : B. charge
Explanation:-

3. The capacitance of a parallel plate capacitor is 2micro Farads. when a glass plate is inserted between its two plates, its potential reduces to 1/10 of the original value. The value of dielectric constant is _____

A. 4
B. 8
C. 10
D. 20

Answer : C. 10
Explanation:-

4. A tap supplies water at 32 degree C. A man takes 1 litre of water per minute at 47 degree C from the geyser. The power of the geyser is

A. 1050W
B. 8000W
C. 1575W
D. 525W

Answer :A. 1050W
Explanation:-

5. Which of the following theorems is used in communication systems?

A. Nortons
B. Thevenins
C. Reciprocity
D. Maximum power transfer theorem

Answer : D. Maximum power transfer theorem
Explanation:-

6. In a network, the open circuit is made across the load terminals, the voltage measured is 10volts and shirt circuit is made across the same load terminals, the current measurement is 5A. Across the same load terminals if the load resistance connected is 3 ohm, then the current flow is

A. 1A
B. 3A
C. 2A
D. 5A

Answer : C. 2A
Explanation:-

7. In a level compound generator, full load voltage is found to be _____ the terminal voltage

A. lesser than
B. Higher than
C. Equal to
D. Much lesser than

Answer : C. Equal to
Explanation:-

8. AT/m is the unit of

A. mmf
B. reluctance
C. magnetic flux density
D. Magnetising force

Answer : D. Magnetising force
Explanation:-

9. A portion of a conducting wire is bent in the form of a semicircle of radius x carries a current of I Amps. At the centre of the semi circle, the magnetic field will be

A. Zero
B. µ0I / 4x
C. µ0I / 8x
D. µ0I / 2x

Answer : B. µ0I / 4x
Explanation:-

10. A wave wound DC generator with 4poles, 1000 conductors having flux/pole of 0.06wb is developing a voltage of 200V. Then the speed of the armature will be ______

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

Answer : B. 100rpm
Explanation:-

11. In speed control of DC motors, which method will give above and rated speeds?

A. armature control only
B. field control only
C. Both armature and field control
D. emf injection methods

Answer : B. field control only
Explanation:-

12. Which of the following methods is the most economical for finding no load losses of a DC shunt motor?

A. Hopkinson's test
B. Swinburne's test
C. Retardation test
D. Brake test

Answer : B. Swinburne's test
Explanation:-

13. The ampere hour efficiency of a lead acid battery is about

A. 25%
B. 90%
C. 60%
D. 100%

Answer : B. 90%
Explanation:-

14. If the current in the armature of a DC series motor before saturation is reduced by 50%, the torque of the motor will be ______

A. 50%
B. 25%
C. 150%
D. 200%

Answer : B. 25%
Explanation:-

15. Which of the following materials exhibit negative temperature coefficient of resistance as the temperature increases?

A. copper
B. silver
C. silicon
D. ACSR conductor

Answer : C. silicon
Explanation:-

16. The direction of rotation of a DC motor can be determined by

A. fleming's right hand rule
B. fleming's left hand rule
C. lenz;s law
D. ampere's law

Answer : B. fleming's left hand rule
Explanation:-

17. The purpose of DC motor starter is to

A. provide starting torque
B. limit initial inrush current
C. provide high speed
D. regulate supply voltage

Answer : B. limit initial inrush current
Explanation:-

18. The efficiency of a DC machine is maximum when variable losses are equal to

A. constant losses
B. stray losses
C. friction losses
D. eddy current losses

Answer :A. constant losses
Explanation:-

19. In order to increase the range of a voltmeter ________ with the voltmeter

A. a low resistance is connected in series
B. a low resistance is connected in parallel
C. a high resistance is connected in series
D. a high resistance is connecetd in parallel

Answer :C. a high resistance is connected in series
Explanation:-

20. Which of the following materials is used as dielectric material?

A. plastic
B. tungsten
C. ceramics
D. germanium

Answer : C. ceramics
Explanation:-

21. A permanent magnet should have

A. high retentivity
B. low retentivity
C. zero retentivity
D. low permeability

Answer : A. high retentivity
Explanation:-

22. When the electrical supply is ON, then which of the following instruments should not be used ?

A. wattmeter and power factor meter
B. frequency meter and energy meter
C. phase sequence meter and tong tester
D. ohm meter and megger

Answer : D. ohm meter and megger
Explanation:-

23. A current of (120-j50) A flows through a circuit when the applied voltage is (8+j12) V. what is the magnitude of circuit impedance?

A. 0.0635 ohm
B. 1.325 ohm
C. 1.52 ohm
D. 0.0256 ohm

Answer :A. 0.0635 ohm
Explanation:-

24. DC Cromptons potentiometer is used to calibrate

A. voltmeter only
B. ammeter only
C. energy meter only
D. both voltmeter and ammeter

Answer : D. both voltmeter and ammeter
Explanation:-

25. LVDT is a transducer which converts

A. Linear displacement into proportional electrical signal
B. low voltage signal into high frequency signal
C. high frequency signal into low frequency signal
D. acceleration into pressure

Answer : A. Linear displacement into proportional electrical signal
Explanation:-

26. Gravity control technique in a measuring instrument can be employed for

A. horizontally mounted measuring instruments only
B. vertically mounted measuring instruments only
C. both horizontally and vertically measuring instruments only
D. independent of mounting of measuring instruments

Answer : B. vertically mounted measuring instruments only
Explanation:-

27. Two wattmeters are used to measure power inout to a 3 phase balanced load. The reading in one wattmeter is twise that of the second. The power factor of the load is

A. zero lag
B. 0.866
C. 0.5
D. 1

Answer :B. 0.866
Explanation:-

28. A series RLC Circuit draws current at leading power factor at ____

A. resonant frequency
B. below resonant frequency
C. above resonant frequency
D. all frequencies

Answer : B. below resonant frequency
Explanation:-

29. If a transformer primary is energised from a square wave voltage source, then its output voltage will be _____

A. zero
B. a sine wave
C. a triangular wave
D. a pulse wave

Answer :D. a pulse wave
Explanation:-

30. In an AC circuit, the current and voltage are out of phase by 90 degrees. The ammeter reads 2A and voltmeter reads 1000V. The power consumed is

A. zero
B. 2000w
C. 1000w
D. 180w

Answer : A. zero
Explanation:-

31. In which transformer connection, teritery winding is used?

A. star-delta
B. delta-delta
C. delta-star
D. star-star

Answer : D. star-star
Explanation:-

32. When a three phase connection can be used in a transformer to introduce a phase difference of 30 degrees its output and corresponding input voltage?

A. star-star
B. star-delta
C. delta-delta
D. delta-V

Answer : B. star-delta
Explanation:-

33. An auto transformer is more economical in saving of material if

A. turns ratio is nearly unity
B. rating of transformer is low
C. turns ratio is 0.5
D. Rating of transformer is high

Answer : A. turns ratio is nearly unity
Explanation:-

34. When a parallel ac circuit is in resonance, it _______

A. draws maximum current
B. offers minimum impedance
C. is called as rejector circuit
D. has no branch currents

Answer : C. is called as rejector circuit
Explanation:-

35. The phase difference between voltage and current wave through a circuit elements is given as 30 degrees, the essential condiction is that _____

A. both the waves have zero at the same time
B. both the waves must have identical peak values
C. both the waves must have the same frequency
D. it should be pure resistive circuit

Answer :C. both the waves must have the same frequency
Explanation:-

36. In transformers laminated core is used to reduce

A. hysteresis loss
B. eddy current loss
C. copper loss
D. iron loss

Answer : B. eddy current loss
Explanation:-

37. A 5KVA, 200/100V, single phase transformer delivers 50 A at rated voltage, the inout current will be ______

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

Answer :A. 25A
Explanation:-

38. A single phase transformer has a turn ratio of 4:1, If the secondary winding has a resistance of 1 ohm, the secondary resistance as referred to the primary will be _____

A. 16ohm
B. 4ohm
C. 0.0625ohm
D. 0.25ohm

Answer : A. 16ohm
Explanation:-

39. The voltage regulation of a transformer would be negative generally at the following power factor _____

A. unity
B. 0.8 lagging
C. 0.2 leading
D. zero lagging

Answer :C. 0.2 leading
Explanation:-

40. For a 3 phase induction motor, operating at slip s , the ratio of gross power output to air gap power is equal to _____

A. (1-s)^2
B. (1-s)
C. √(1-s)
D. (1-√s)

Answer : B. (1-s)
Explanation:-

41. A 3 phase, 6 pole induction motor connected to a 50 Hz supply runs at 975rpm on full load. Its full load slip is _____

A. 25%
B. 1.5%
C. 2.5%
D. 2.0%

Answer : C. 2.5%
Explanation:-

42. The ratio of starting torque with star-delta starter to the starting torque with direct on line starting is

A. 1/(√3)
B. √3
C. 1/3
D. 3

Answer : C. 1/3
Explanation:-

43. A field excitation of 20A in a certain alternator results in an armature of 400A in short circuit and a terminal voltage of 2000V on open circuit. The magnitude of the internal voltage drop with in the machine at a current of 200A is _____

A. 1V
B. 10V
C. 100V
D. 1000V

Answer : D. 1000V
Explanation:-

44. In a capacitor start motor, the capacitor is connected _______

A. in series with auxiliary winding only
B. in series with main winding only
C. in parallel with auxiliary winding only
D. anywhere in the motor

Answer : A. in series with auxiliary winding only
Explanation:-

45. In a single phase induction motor running at a slip of 5 % with reference to forward field, the slip with reference to backward field is

A. 0
B. 0.95
C. 1.95
D. 2.0

Answer : C. 1.95
Explanation:-

46. When a synchronous motor is run as a synchronous capacitor, it operates _______

A. with leading power factor without any load
B. with leading power factor supplying loads
C. with lagging power factor without any load
D. with lagging power factor supplying loads

Answer : A. with leading power factor without any load
Explanation:-

47. The charging current in a transmission line increases due to corona effect because corona increases _____

A. line current
B. effective line voltage
C. power loss in lines
D. effective conductor diameter

Answer : D. effective conductor diameter
Explanation:-

48. Hunting in synchronous motors occur due to

A. changes in excitaion
B. increase in supply to motors
C. decrease in supply to motor
D. sudden load variations

Answer : D. sudden load variations
Explanation:-

49. The cooling medium used in large sized synchronous machine is usually

A. hydrogen
B. air
C. water
D. mineral oil

Answer :A. hydrogen
Explanation:-

50. The graph for V curves for a synchronous motor is drawn between

A. field current and armature current
B. power factor and field current
C. armature current and power factor
D. terminal voltage and power factor

Answer : A. field current and armature current
Explanation:-

51. An overexcited synchronous motor operates at ______

A. unity Pf
B. Leading pf
C. lagging pf
D. zero pf(lagging)

Answer : B. Leading pf
Explanation:-

52. Synchronous reactnace is

A. sum of both leakage reactance and armature reaction reactance
B. armature reaction reactance
C. difference of armature reaction reactance and leakage reactance
D. leakage reactance

Answer : A. sum of both leakage reactance and armature reaction reactance
Explanation:-

53. Water hammer is developed in

A. pen stock
B. turbine
C. alternator
D. surge tank

Answer : A. pen stock
Explanation:-

54. The maximum demand of a consumer is 2KW and the daily energy consumption is 24units, The load factor is

A. 10%
B. 40%
C. 50%
D. 30%

Answer :C. 50%
Explanation:-

55. Boron is used in nuclear reactor as

A. fuel
B. heat exchanger
C. control rods
D. moderator

Answer : C. control rods
Explanation:-

56. For high discharges which of the following turbines is used in hydro power plants?

A. pelton turbine
B. francis turbine
C. kaplan turbine
D. deriaz turbine

Answer : C. kaplan turbine
Explanation:-

57. A plant has an average load of 20MW when the load factor is 50%. Its diversity factor is 20%. Sum of maximum demands of all load amounts to ______

A. 12MW
B. 8MW
C. 6MW
D. 4MW

Answer :B. 8MW
Explanation:-

58. Generally Buchholz relay is used in power system for protection against

A. faukts in generators
B. faults in transmission lines
C. earth faults primarily in alternators
D. internal faults in transformer

Answer :D. internal faults in transformer
Explanation:-

59. Ground wires are used in transmission lines to

A. suppress arcing earth
B. shield the lines against lightning strokes
C. provide retuen paths for zero sequence current
D. provide mechanical rigidity to the lines and towers

Answer : B. shield the lines against lightning strokes
Explanation:-

60. Lightening arrestors are normally made of

A. silica gel
B. calcium hydroxide
C. thyrite
D. Tungesten

Answer : C. thyrite
Explanation:- A lightening arrestor have a block of a semi conductor material such as silicon carbide or zinc oxide. "Thyrite" was the trade name used by General Electric

61. A relay used on short transmission lines is

A. mho relay
B. reactance relay
C. impedance relay
D. admittance relay

Answer :B. reactance relay
Explanation:-

62. The normal frequency rms voltage that appears across the circuit breaker pole after final arc extinction has occured is called the

A. supply voltage
B. restriking voltage
C. recovery voltage
D. breaking voltage

Answer : C. recovery voltage
Explanation:-

63. Ring main distribution system is preferred to radial distribution system, because

A. voltage drop in the feeder is less
B. power factor is high
C. it is expensive
D. power factor is low

Answer : A. voltage drop in the feeder is less
Explanation:-

64. Ferranti effect in long lines causes increase of

A. sending end voltage
B. receiving end voltage
C. load power factor
D. failure of transformer

Answer :B. receiving end voltage
Explanation:-

65. The GMR of a conductor of radius r is

A. r
B. 1/r
C. 0.778r
D. 1/0.778r

Answer : C. 0.778r
Explanation:-

66. The purpose of gaurd ring is

A. to equalize various capacitors
B. to equalize voltage drops across insulator units
C. to equalize the various inductances
D. to gaurd against heavy voltages

Answer : B. to equalize voltage drops across insulator units
Explanation:-

67. Transmission lines are transposed mainly to

A. reduce copper loss
B. reduce skin effect
C. prevent interference with neighboring telephone lines
D. prevent short circuit between any two lines

Answer : C. prevent interference with neighboring telephone lines
Explanation:-

68. While designing distributor for following parameters is important to consider

A. voltage drop
B. temperature rise
C. corona effect
D. insulation level

Answer : A. voltage drop
Explanation:-

69. Sheaths are used in cables to

A. provide proper insulation
B. provide mechanical strength
C. prevent increases of moisture
D. allow the moisture contents into the cables

Answer :C. prevent increases of moisture
Explanation:-

70. A 66kv system has string insulator having five discs and the earth to disc capacitance ratio of 0.10, the the string efficiency will be around

A. 89%
B. 75%
C. 67%
D. 55%

Answer :D. 55%
Explanation:-

71. Auto reclosing is used in case of

A. lightning arrestor
B. air blast CB
C. bulk oil CB
D. minimum oil CB

Answer : B. air blast CB
Explanation:-

72. HVDC Transmission is preferred to EHVAC because

A. HVDC terminal equipment is inexpensive
B. VAR compensation is not required in HVDC system
C. system stability can be improved
D. harmonics problem is a voided

Answer : C. system stability can be improved
Explanation:-

73. In a sub urban service compared to urban service

A. The coasting period is smaller but free running period is longer
B. The coasting period is longer and free running period is also absent
C. relatively high avergae speed
D. only free running period is very long

Answer : B. The coasting period is longer and free running period is also absent
Explanation:-

74. In traction systems, schedule speed is defined as

A. distance/(time for run)
B. distance/(time to stop)
C. distance/(time for run+time to stop)
D. distance/(time during which the speed is constant)

Answer : C. distance/(time for run+time to stop)
Explanation:-

75. on the speed time curve in traction, the period of time where tractive effort is equal to resistance to the train movement is called

A. notching up period
B. pre running period
C. coasting period
D. retardation period

Answer :B. pre running period
Explanation:-

76. Quadrilateral speed time curve is used for _____

A. sub urban service only
B. urban service only
C. main line service only
D. both urban and sub urban services

Answer : D. both urban and sub urban services
Explanation:-

77. longer coasting period of a train results in

A. higher schedule speed
B. lower specific energy consumption
C. higher retardation
D. higher acceleration

Answer : B. lower specific energy consumption
Explanation:-

78. The drive motor for locomotive would be

A. synchronous motor
B. DC series motor
C. universal motor
D. schrage motor

Answer : B. DC series motor
Explanation:-

79. Tumbler switches are made of

A. Iron
B. rubber
C. plastic
D. Bakelite

Answer : D. Bakelite
Explanation:-

80. A britannia joint is used in

A. bare overhead wires
B. underground cables
C. conduit wiring
D. power wiring

Answer : A. bare overhead wires
Explanation:-

81. The maximum permissible value of earth resistance for satisfactory opertion of large power station is

A. 2ohm
B. 1ohm
C. 0.5ohm
D. 5ohm

Answer : C. 0.5ohm
Explanation:-

82. The only wiring which has to be planned well before starting of a house construction work and executed along with the construction is _______

A. cleat wiring
B. conduit surface wiring
C. batten wiring
D. conduit concealed wiring

Answer : D. conduit concealed wiring
Explanation:-

83. According to IE code, the colour code for the neutral is

A. Red
B. Blue
C. Black
D. Green

Answer : C. Black
Explanation:-

84. A semiconductor device field effect transistor(FET)

A. has a very high inout impedance
B. depends on minority carrier flow
C. uses a forward biased junction
D. uses a high concentration emitter junction

Answer :A. has a very high inout impedance
Explanation:-

85. peak inverse voltage of bridge rectifier is

A. Vm
B. 2Vm
C. 0.5Vm
D. 4m

Answer : A. Vm
Explanation:-

86. In wien bridge oscillator the phase introduce by feedback network

A. 0 degrees
B. 180 degrees
C. 60 degrees
D. 270 degrees

Answer : A. 0 degrees
Explanation:-

87. Decimal equivalent of (0.0100)2 is ______

A. 0.75
B. 0.375
C. 0.825
D. 0.250

Answer : D. 0.250
Explanation:-

88. The output of a 2 inout gate is 0 if and only if its inouts are equal, it is true for ______

A. AND
B. EX-OR
C. OR
D. NOR

Answer : B. EX-OR
Explanation:-

89. When a Thyristor is reverse biased, the number of blocked P-N junctions is ______

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

Answer : B. 2
Explanation:-

90. For normal Thyristors, turn-on time is _____

A. Less than turn-off time(tq)
B. More than tq
C. Equal to tq
D. about half of the tq

Answer : A. Less than turn-off time(tq)
Explanation:-

91. A single phase fully controlled bridge converter supplies an inductive load and the supply voltage is 230V and if the firing angle is π/6 radians, what is the average output voltage nearly?

A. 180 V
B. 220 V
C. 150 V
D. 130 V

Answer : A. 180 V
Explanation:-

92. A freewheeling diode is placed across the inductive load will provide ______

A. quick turn on
B. slow turn off
C. reduced utilization factor
D. improved power factor

Answer : D. improved power factor
Explanation:-

93. The 8051 Micro controller has a/an _____ bit CPU

A. 16
B. 8
C. 32
D. 4

Answer : B. 8
Explanation:-

94. Two identical SCR's are connected back to back in series with a R-L (continous mode) (α ∠ ∅) load. If each SCR is fired at 90 degrees, a PMMC voltmeter across the load would read _________ (where α is firimg angle. ∅ is load angle)

A. peak voltage
B. (peak voltage)/π
C. Zero voltage
D. half of peak voltage

Answer : C. Zero voltage
Explanation:-

95. Solid angle subtended by a sphere at its centre is _____ steradians

A. 2π
B. 4π
C. π
D. zero

Answer : B. 4π
Explanation:-

96. The colour of light depends on ______

A. wavelength
B. speed of light
C. time period
D. phase constant

Answer : A. wavelength
Explanation:-

97. Determine the distance for a 25 C.P lamp from a normally placed screen in order that the illumination shall be 5 lux?

A. 2.24 m
B. 5 m
C. 1 m
D. 3 m

Answer :A. 2.24 m
Explanation:-

98. If a table fan running smoothly starts giving up smoke, the reason is ______

A. short circuited winding
B. failure of the centrifugal switch to open the starting winding
C. bearing failure
D. overload

Answer : A. short circuited winding
Explanation:-

99. Function of fusible safety plug in a geyser is _______

A. It protect the geyser against blasting due to excessive steam pressure
B. it protects the heating element against burning
C. it releases the extra water out of the geyser
D. it protects the thermostat of the geyser

Answer : A. It protect the geyser against blasting due to excessive steam pressure
Explanation:-

100. When a fluorescent lamp shows a dense blackening at each end it could be possible mean that the ______

A. gas filled in the lamp was wrong
B. lamp was started infrequently
C. starter was working improperly
D. lamp was new

Answer : C. starter was working improperly
Explanation:-