Junior Instructor-Technical Power Electronics System Industrial Training Department 468/2016 Answer Key

Post : Junior Instructor-Technical Power Electronics System
Department : Industrial Training Department
Category Code : 468/16
Qualification : Master's Degree in Painting; S.S.L.C. + National Diploma in Painting
Question Paper Code : 78/2017/OL
Date of Test : 19-09-2017

1. Silicon has an atomic number of 14, this means the atom has 14 ____________.
   • Neutrons
   • Electrons
   • Protons and neutrons combined together
   • Valence electrons
   
   
2. The most commonly used electrical conductor is ___________.
   • Lead
   • Tin
   • Brass
   • Copper
   
   
3. The opposition offered to the movement of electrons/current flow is known as __________.
   • Electric resistance
   • Current
   • Voltage
   • None of these
   
   
4. In a meter one main scale division is 5 volts, and it is divided into 10 small-scale divisions. The meter can measure a minimum voltage of _____________.
   • 5 V
   • 0.5 V
   • 0.1 V
   • 1 V
   
   
5. As the field intensity (H) in the core is increased, the flux density (B) ___________.
   • Increases
   • Decreases
   • Becomes zero
   • Does not change
   
   
6. Material which can be strongly magnetised are known as ____________ materials.
   • Paramagnetic
   • Diamagnetic
   • Ferromagnetic
   • Pure magnet
   
   
7. What material is used for making armature core?
   • Silicon steel
   • Aluminium
   • Copper
   • Mild steel
   
   
8. The speed of a universal motor ____________.
   • Remains constant to the applied load
   • Is directly proportional to the applied load
   • Is inversely proportional to the applied load
   • Becomes zero when load is applied
   
   
9. The basic unit of inductance is ___________.
   • Farad
   • Webber
   • Henry
   • Hertz
   
   
10. Inductive reactance of a coil is directly proportional to the ___________.
    • Alternating current following through it
    • Induced emf in it
    • Frequency of AC flowing through it
    • All the parameters mentioned at A, B and C
    
    
11. Two capacitors C1 = 1 nf and C2 = 10 nf, are connected in series and applied to the battery voltage V = 11 V. What are the voltages across the capacitors?
    • VC1 = 5.5 V; VC2 = 5.5 V
    • VC1 = 10 V; VC2 = 1 V
    • VC1 = 1 V; VC2 = 10 V
    • VC1 = 0 V; VC2 = 11 V
    
    
12. Mutual induction is obtained by placing two current carrying coils ___________.
    • Side by side close to each other
    • Perpendicular to each other
    • Far away from each other
    • Both 'Side by side close to each other' and Perpendicular to each other
    
    
13. The fundamental unit of measurement of resistance is ____________.
    • Ohm
    • Milli ohm
    • Kilo ohm
    • Mega ohm
    
    
14. For measuring unknown resistance, initially choose ____________.
    • The highest ohms range
    • The lowest ohms range
    • Any ohms range
    • R × 10 ohms range
    
    
15. When three resistors R1, R2 and R3 are connected in series, the total resistance R_T =
    • R1 + R2 + R3
    • R1 × R2 × R3
    • 1/R1 + 1/R2 + 1/R3
    • 1/R1 × 1/R2 × 1/R3
    
    
16. Magnetic lines are concentrated at ___________.
    • At the centre of magnet
    • Anyone end of the magnet
    • Along the magnet uniformly
    • Both the ends of the magnet
    
    
17. Generation and distribution of AC power in India is normally ___________.
    • Single phase
    • 3 phase
    • 2 phase
    • Either 2 phase or 3 phase
    
    
18. The principle of operation of universal motor, similar to __________.
    • DC shunt motor
    • DC series motor
    • DC short-shunt compound motor
    • DC long-shunt compound motor
    
    
19. The flux density of a coil can be increased by inserting a __________.
    • Brass core
    • Iron core
    • Rubber core
    • Plastic core
    
    
20. The frequency of induced emf in an AC generator is given by ___________.
    • 120/PN
    • 120P/N
    • PN/120
    • 120N/P
    
    
21. A charged capacitor acts like a ____________.
    • Temporary voltage source
    • Magnetic energy source
    • Constant current source
    • Switch
    
    
22. The relation between frequency of an AC signal (F) and time period (T) is __________.
    • F=T²
    • F = 2T
    • F = 1/T
    • F = 1/2T
    
    
23. A motor converts electrical energy into _____________.
    • Magnetic energy
    • Mechanical energy
    • Potential energy
    • Chemical energy
    
    
24. When 2 inductors are in parallel, the effective value of inductance is given by LT = __________.
    • L1 + L2
    • L1 × L2/L1 + L2
    • L1 × L2
    • L1 + L2/L1 × L2
    
    
25. A transformer is an electrical device used to __________.
    • change the frequency of applied AC voltage
    • transfer electrical energy from one circuit to another without any direct electrical connection
    • convert applied DC into AC
    • convert applied AC into DC
    
    
26. A 3-phase transformer has ____________.
    • 1 primary and 3 secondary windings
    • 3 primary and 1 secondary windings
    • 3 primary and 3 secondary windings
    • 3 primary and 6 secondary windings
    
    
27. A transformer has 800 turns in its primary winding and 200 in its secondary what is the primary voltage, if the secondary voltage is 40 V? Assume transformer losses as negligible?
    • 8 V
    • 16 V
    • 40 V
    • 160 V
    
    
28. Efficiency of a transformer is the ratio of ___________.
    • Output power to input power
    • Input power to output power
    • Input current to output current
    • Output current to input current
    
    
29. The basic unit of capacitance is ____________.
    • Ohm
    • Farad
    • Henry
    • Mho
    
    
30. The relationship between charge (Q), voltage (V) and capacitance (C) of a capacitor is ____________.
    • C = Q/V
    • C = QV
    • C=Q²V
    • C = V/Q
    
    
31. Identify the instrument which is NOT used for measurement of capacitance _________.
    • Digital capacitance meter
    • AC bridge
    • RLC meter
    • Kelvin bridge
    
    
32. The capacitive reactance Xc is given by __________.
    • 2πFC
    • 1/2πFC
    • 2π/FC
    • FC/2π
    
    
33. Current flowing through a capacitor is given by ___________.
    • V.Xc
    • V²/Xc
    • V/Xc
    • V²C
    
    
34. A semi conductor in its pure form is referred to as __________.
    • Intrinsic semiconductor
    • Extrinsic semiconductor
    • Crystal semiconductor
    • Doped semiconductor
    
    
35. The process of adding impurities to a pure semiconductor __________.
    • Diffusion
    • Forming
    • Etching
    • Doping
    
    
36. The potential difference across a PN junction is referred to as _________.
    • Potential difference
    • Barrier potential
    • Reverse potential
    • PN potential
    
    
37. When a germanium diode is connected in forward biased mode the voltage across the diode will be ___________.
    • 0.7 V
    • 0.3 V
    • Is equal to applied voltage
    • 0 V
    
    
38. When a diode is tested using an ohm meter. It indicates the low resistance in both direction. The condition of the diode is ___________.
    • Open
    • Short
    • Leaky
    • Good
    
    
39. A forward biased diode starts conducting when the applied voltage reaches certain voltage known as _________.
    • End-in voltage
    • Barrier voltage
    • Peak voltage
    • Saturation voltage
    
    
40. What value of the voltage is obtained directly from the wave form shown on a C.R.O when connected across the secondary of a transformer?
    • Peak value
    • R.M.S. value
    • Peak-to-peak value
    • Average value
    
    
41. The main component used in a ripple filter circuit is the ___________.
    • Capacitor
    • Resistor
    • Diode
    • Transformer
    
    
42. The maximum forward current of an LED is about ____________.
    • 10 mA
    • 50 mA
    • .5 A
    • 1.0 A
    
    
43. Which colour LED has the lowest forward voltage drop?
    • Red
    • Orange
    • Green
    • Yellow
    
    
44. The time taken for etching PCB is in the range of ___________.
    • 5 to 20 minutes
    • 20 to 40 minutes
    • 1 to 2 hours
    • More than 2 hour
    
    
45. The PCB side on which components are mounted is referred to as ___________.
    • Copper side
    • Component side
    • Solder side
    • Trackside
    
    
46. The chemical used for removing copper from copper clad boards is called __________.
    • Thinner
    • Remover
    • Eraser
    • Etchant
    
    
47. In amplifiers, transistors are used for ___________.
    • Enlarging small electronic signals
    • Switching purposes
    • Reducing electronic signals
    • Both Enlarging small electronic signals and Switching purposes
    
    
48. A transistor can be thought of as two PN junction diodes connected as ____________.
    • PNPN
    • PNNP
    • NPNP
    • NNPP
    
    
49. The advantage of transistors over vacuum tubes is ____________.
    • Very small size
    • Minimum power loss in the form of heat
    • Low operating voltage
    • All of these
    
    
50. NPN transistors are preferred to PNP transistors for ___________.
    • Higher switching speed
    • Easy use in +ve supply rail
    • A wide range of operating temperature
    • Both 'Higher switching speed' and 'Easy use in +ve supply rail'
    
    
51. Small signal amplifiers are also known as ___________.
    • Large power amplifiers
    • Medium power amplifiers
    • Low power amplifiers
    • Both medium power and low power amplifiers
    
    
52. In transistors, the width of the collector layer is __________.
    • Much less than the base region
    • Much wider than the base region
    • Much less than the emitter region
    • Same as that of the base region
    
    
53. The resistance measured by a multimeter between the anode and the cathode of good SCR should be __________.
    • Low
    • Medium
    • High
    • Infinity
    
    
54. In speed control circuits for DC motors using two SCR's _____________.
    • Each SCR conducts at any time
    • One SCR conducts in positive half cycle and the other in negative half cycle
    • Both SCR's conduct at a time
    • Only one SCR conducts and the other does not conduct
    
    
55. Most common application of UJT is ____________.
    • Schmitt trigger
    • Bistable multivibrator
    • Relaxation oscillator
    • Timer
    
    
56. DIAC is basically ____________.
    • A PNP/NPN transistor
    • A PNP/NPN transistor with no base connection
    • A 4 layered NPNP device
    • None of these
    
    
57. The speed of an AC motor can be controlled by using ____________.
    • SCR
    • TRIAC
    • DIAC with SCR
    • DIAC with TRIAC
    
    
58. A power MOSFET is capable to handle current upto ___________.
    • 1 A
    • 50 A
    • 10 A
    • 100 A
    
    
59. An IGBT is a hybrid form of ____________.
    • A diode and a transistor
    • A transistor and SCR
    • A bipolar transistor and a MOSFET
    • A FET and a MOSFET
    
    
60. MOSFET's are used in ______________.
    • Inverters
    • SMPS
    • UPS
    • All these
    
    
61. High speed switching can be obtained using a ____________.
    • Power IGBT
    • PNP transistor
    • Diode
    • Vibrator
    
    
62. Power MOSFET and power IGBT are __________
    • One and the same device
    • Quite different devices
    • Similar semiconductor devices
    • Replaceable devices
    
    
63. Which one of the following semiconductor device may be used as a light sensor?
    • Photo diode
    • Photo transistor
    • LDR
    • Any one of these
    
    
64. The material used for making optic-fibre cable in general is ___________.
    • Copper
    • Transparent plastic
    • Aluminium
    • Steel
    
    
65. Which one of the following IC contains NOT gates ___________?
    • IC 7400
    • IC 7404
    • IC 7402
    • IC 7408
    
    
66. Which of the following gates gives a high output with all its inputs high
    • NOT
    • NOR
    • OR
    • X-OR
    
    
67. The logic gate which has 'high' output when its inputs are different is ___________.
    • NOR
    • EX-OR
    • NAND
    • EX-NOR
    
    
68. The biggest advantage of ECL is ___________.
    • High fan out
    • High speed
    • Low power consumption
    • High density
    
    
69. The term CMOS stands for
    • Capacitance Metal Oxide Semiconductor
    • Complimentary Metal Oxide Semiconductor
    • Charged Metal Oxide Semiconductor
    • Copper Metal Oxide Semiconductor
    
    
70. A BCD-to-Decimal decoder converts
    • BCD code to decimal digits
    • Binary code to decimal digits
    • BCD code to binary code
    • BCD code to grey code
    
    
71. The number of flip-flops required to construct a decade counter is ___________.
    • 2
    • 3
    • 4
    • 6
    
    
72. The number of NOR gates required to construct R-S flip-flop is ____________.
    • 1
    • 2
    • 3
    • 4
    
    
73. The basic building block of a counter is ___________.
    • AND gate
    • OR gate
    • NAND gate
    • Flip-flops
    
    
74. ROM is a non-volatile memory. The name of volatile memory is _______________.
    • PROM
    • SRAM
    • EPROM
    • RAM
    
    
75. Modern data storage device named 'pen drive' has a capacity of storing 16 GB data, what does it mean
    • 16 × 10⁹bytes
    • 16 × 10⁶bytes
    • 16 × 10⁹bits
    • 16 × 10⁶bits
    
    
76. An OP-AMP is designed to amplify
    • AC voltage
    • DC voltage
    • Both AC and DC voltage
    • Pulse signals only
    
    
77. DC operating voltage of IC 555 is
    • +5 to +18 V
    • +18 to +36 V
    • +5 to +28 V
    • +18 to +48 V
    
    
78. Approximately what is the frequency limit of the optical fibre
    • 20 GHz
    • 1 MHz
    • 100 MHz
    • 40 GHz
    
    
79. The higher the index number of a fibre optic cable _____________.
    • The higher the speed of light
    • The lower the speed of light
    • Has no effect on the speed of light
    • The shorter the wavelength propagation
    
    
80. The three major groups in the optical system are
    • The components, the data rate and response time
    • The source, the link and the receiver
    • The transmitter, the cable and the receiver
    • The source, the link and the detector
    
    
81. During which decade did India see a negative population growth?
    • 1871-81
    • 1911-21
    • 1921-31
    • 1941-51
    
    
82. Kharif Crops are harvested in
    • October-November
    • June-July
    • March-April
    • January-February
    
    
83. Fiscal policy in India is formulated by
    • The Reserve Bank of India
    • The Planning Commission
    • The Finance Ministry
    • None of these
    
    
84. On which date Indian Independence Act of 1947 got royal assent?
    • 19th June 1947
    • 1st August 1947
    • 10th August 1947
    • 18th July 1947
    
    
85. Who among the following is known as ''Mother of Indian Revolution''?
    • Bhikaji Rustam Kama
    • Sarojini Naidu
    • Aruna Asaf Ali
    • Suchetha Kripalani
    
    
86. In which five year plan India opted for mixed economy?
    • Fourth
    • Third
    • First
    • Second
    
    
87. Which district in Kerala leads in the production of cashew nuts?
    • Kollam
    • Wayanad
    • Kannur
    • Kozhikkode
    
    
88. Father of local self government in India
    • Lord Canning
    • Lord Rippon
    • Lord Lytton
    • Lord Wellesley
    
    
89. How many times Gandhiji visited Kerala?
    • Two times
    • Four times
    • Five times
    • Three times
    
    
90. Who was the first Portuguese Viceroy in Kerala?
    • Vasco da Gama
    • Nicolo Conti
    • Albuquerque
    • Almeida
    
    
91. The 2017 Udyanotsav festival was held in which of the following cities?
    • Jaipur
    • New Delhi
    • Mysore
    • Ooty
    
    
92. Who has won the 2017 Men's Singles Australian Open Tennis tournament?
    • Roger Federer
    • Andy Murray
    • Rafael Nadal
    • Noval Djokovic
    
    
93. Which of the following state has attained 100% Aadhaar saturation in India?
    • Tamil Nadu
    • Kerala
    • Himachal Pradesh
    • Assam
    
    
94. Which among the following is known as ''Sairandhri Vanam''?
    • Periyar National Park
    • Silent Valley National Park
    • Shenthurani National Park
    • Mudumalai National Park
    
    
95. Who wrote the famous book ''We the People''?
    • R.K. Laxman
    • Chetan Bhagath
    • Arundhati Roy
    • Nani Palkhivala
    
    
96. Who was the founder President of NSS?
    • K. Kelappan
    • Mannathu Padmanabhan
    • Kontor Krishnapillai
    • Valparambil Valayudha Pillai
    
    
97. Who called Sree Narayana Guru as the ''Second Buddha''?
    • Chattampi Swamikal
    • G. Sankara Kurup
    • Vakkom Abdul Khader Moulavi
    • Vagbhadananda
    
    
98. The social reformer who said ''Mind is God''?
    • Brahmananda Shivayogi
    • Pandit Karuppan
    • Poikayil Yohannan
    • Thycaud Ayya
    
    
99. The headquarters of ''Prathyaksha Raksha Daiva Sabha''
    • Kottayam
    • Neyyattinkara
    • Eraviperoor
    • Kainakari
    
    
100. Who started the publication journal called ''Abhinava Kerala''?
     • Nataraja Guru
     • Dr. Palpu
     • Kumaranasan
     • Vagbhadananda