AAI electronics and electrical questions and answers
AAI Electronics and Electrical questions for practice
1. Shuntwound Generators (selfexcited) used for
a) Boosters
b) Charging Batteries
c) a & b are correct
d) None of the above.-Answer
2. If a generator gives spark on commutator the reason is
a) Overload
b) Armature Shortcircuit
c) a & b are correct
d) None of the above.-Answer
3. The equipment required for protection of transformers.
a) Breather
b) Conservator
c) Emergency release .-Answer
d) Temperature Gauge
e) All of the above
4. Why flux is used for soldering?
a) To remove oxides from the surface to be soldered
b) it is used as a paste
c) without flux cannot solder
d) None of the above.-Answer
5. Empire cloth is used for
a) Overhead lines
b) switches.-Answer
c) Insulating the machines while winding
d) None of the above
6. Thermal efficiency is defined as the ratio of
a) Output Energy / Input Energy.-Answer
b) (Output Energy / Input Energy) x 100
c) Useful heat / Total heat
d) (Useful heat / Total heat) x 100
7. Moving iron attraction type meter used for
a) Measure current in A.C
b) Measure current in D.C.-Answer
c) a & b are correct
d) None of the above
8. Moving coil instrument used in
a) ac only
b) dc only
c) both ac & dc .-Answer
d) None of the above
9. Fluorescent lamp circuit is a
a) Series Circuit
b) Parallel Circuit
c) Combination of series & Parallel Circuit.-Answer
d) None of the above
10. In Fluorescent lamp circuit why choke is used
a) it gives low Voltage impulse for starting lamp
b) It gives high Voltage impulse for starting lamp
c) It prevent the lamp from overvoltages.-Answer
d) it acts as a stabillizer
11. Alternators are rated in
a) KW .-Answer
b) KVA
c) KVAR
d) None of the above
12. The inverse of reluctance is called
a) Permence.-Answer
b) Permittance
c) Saturation
d) None of the above
13. Megger instrument is used for
a) Testing the insulation resistance of the circuit.-Answer
b) Voltage measurement
c) Current measurement
d) None of the above
14 Cinema Projector works in
a) AC
b) DC
c) Both AC & DC .-Answer
d) None of the above
15. Horse power is the unit of
a) Thermal Power
b) Electrical Power
c) Mechanical Power -Answer
d) None of the above
16. Fusing factor ratio is
a) Current rating of fusing element \ Minimum fusing current
b) Minimum fusing current \ Current rating of fusing element-Answer
c) fusing factor not have ratio
d) None of the above
17. The transformer neutral is earthed in the secondary reason is
a) Prevent from over voltages
b) Prevent from over current
c) For testing the phase at any point-Answer
d) None of the above
18. Hotwire type instrument used in
a) AC only
b) DC only
c) Both AC & DC -Answer
d) None of the above
19. Charging rate for lead acid battery
a) Charging current = capacity \ hour-Answer
b) Charging current = hour \ capacity
c) Charging current = Capacity x Hour
d) None of the above
20. Conductance is a reciprocal of
a) Voltage
b) Current
c) Resistance -Answer
d) None of the above
21. Form factor is defined as the ratio of
a) Average value \ r.m.s value
b) Maximum value \ r.m.s value
c) r.m.s value \ average value-Answer
d) None of the above
22. Maxwellwien bridge is used for measuring
a) Inductance -Answer
b) Capacitance
c) Voltage
d) None of the above
23. 555 timer is compatible with
a) TTL logic circuits
b) CMOS logic circuits
c) TTL & CMOS logic circuits-Answer
d) None of the above
24. AND gate performs
a) Addition
b) Subtraction
c) Divison
d) Multiplication-Answer
25. Output for the following gate is
a) Y = A . B
b) Y = A + B-Answer
c) Y = 0
d) None of the above
26. Choose the associative Law
a) A + ( B + C ) = ( A + B ) + C
b) A ( B + C ) = AB + AC
c) (AB) C = A (BC)-Answer
d) A & C are correct.
27. High voltage ink film resistor voltage range up to
a) 500KV
b) 250KV
c) 725KV
d) 1000KV.-Answer
28. Damping Force produced by
a) air frictions
b) Eddy Current
c) Fluid Friction
d) All of the above.-Answer
29. Which one of the following is high pressure boiler?
a) Lamount Boiler
b) Benson boiler
c) a & b are correct .-Answer
d) None of the above
30. For charging battery the following method is used
a) Variable Current System
b) Constant Current System
c) Constant Voltage System
d) b & c are correct.-Answer
31. Ohm's Law does not apply to
a) Linear Devices
b) nonlinear devices.-Answer
c) Series circuit
d) None of the above
32. Susceptibility is defined as the ratio of
a) intensity of magnetisation \ magnetising force.-Answer
b) magnetising force \ intensity of magnetisation
c) material \ Vacuum
d) None of the above
33 Varistor is a
a) Linear resistor
b) NonLinear resistor.-Answer
c) Capacitor
d) None of the above
34. Battery ratings are in
a) KW
b) KVA
c) AH .-Answer
d) None
35. which one of the following is idempotent law
a) A . A = A
b) A + A = A
c) a & b are correct .-Answer
d) None of the above
36. SMD* is a
a) Transistor
b) Resistor
c) Hard disk drives .-Answer
d) None of the above
37. Which one of the following material is used for Violet LED?
*SMD (Storage Modul e Devi ce)
a) Indium Gallium Nitride .-Answer
b) Boron Nitride
c) Aluminium Nitride
d) Zinc Soloride
38. Capacitor can be used as a
a) Temporary Battery .-Answer
b) Primary Battery
c) Secondary Battery
d) None of the above
39. Match the following List I with List II List I List II
1. Chemical effect a. Leadacid
2. Trickle Charging b. alkaline manganese
3. Primary Battery c. Keep it fully Charged
4. Secondary Battery d. d.c. amperehour meters
a) 1d, 2c, 3b, 4a .-Answer
b) 1c, 2d, 3b, 4a
c) 1a, 2b, 3c, 4d
d) 1b, 2a, 3d, 4c
40. Reciprocal of powerfactor is
a) Apparent Power
b) Active Power
c) Q Factor of a coil.-Answer
d) None of the above
41. Match the following ListI with ListII ListI ListII (Motor Types) (Application)
1. Brushless DC motor a. Vacuum cleaner
2. Universal motor b. Tape drives
3. AC Synchronous motor c. Floppy drives
4. DC Stepper motor d. CD / DVD Players
a) 1a, 2b, 3c, 4d
b) 1c, 2a, 3b, 4d
c) 1d, 2a, 3c, 4d
d) 1d, 2a, 3b, 4c.-Answer
42. Capacitive reactance for singlephase series a.c circuit is
42 Which one of the following test used for testing dc machines
a) Shortcircuit test
b) Back to Back test
c) Brake Test
d) All of the above
44. If transformer secondary is open, which draw some current is known as
a) Secondary current
b) noload primary current
c) noload secondary current
d) None of the above
45. If the generator bearings is hot the reason is
a) eddy current
b) Operation at low speed
c) Less oil
d) None of the above
46. Which one of the following is ptype impurities
a) Phosphorus
b) Aluminium
c) Antimony
d) None of the above
47.Which one of the following is a parts of centrifugal pump
a) Draft tube
b) Breaking jet
c) Impeller
d) All of the above
48. Chopper used to convert
a) Constant dc voltage in to variable dc voltage
b) DC power in to AC power
c) AC power in to DC power
d) None of the above
49 What are the input, output terminal of a transistor in common base circuit configuration
a) Base Input, Collector Output
b) Emitter Input, Collector Output
c) Collector Input, Emitter Output
d) None of the above
50. Common collector amplifier is also called
a) Emitter Follower
b) Register
c) Voltage Regulator
d) None of the above
51 Silicon controlled switch is a
a) 4 terminal PNPN device
b) 4 layer PNPN device
c) 3 layer, 3 terminal PNPN device
d) a & b are correct
52. A tunnel diode is used for
a) Pulse generator
b) Square wave generator
c) Microwave frequencies
d) None of the above
52 Density of fluid is defined as the ratio of
53. Which one of the following device used to measure pressure of a fluid
a) Venturimeter
b) Orifice meter
c) Manometers
d) pitot tube
54. Hydraulic machines which converts
a) hydraulic in to mechanical energy
b) Mechanical energy in to hydraulic energy
c) Mechanical energy in to electrical energy
d) None of the above
55. Apply Kirchoff's current law to below circuit
56. Shuntwound Generators (selfexcited) used for
a) Boosters
b) Charging Batteries
c) a & b are correct
d) None of the above.
57. If a generator gives spark on commutator the reason is
a) Overload
b) Armature Shortcircuit
c) a & b are correct
d) None of the above
58 The equipment required for protection of transformers.
a) Breather
b) Conservator
c) Emergency release
d) Temperature Gauge
e) All of the above
59. Why flux is used for soldering?
a) To remove oxides from the surface to be soldered
b) it is used as a paste
c) without flux cannot solder
d) None of the above
60. Empire cloth is used for
a) Overhead lines
b) switches
c) Insulating the machines while winding
d) None of the above
61. Thermal efficiency is defined as the ratio of
a) Output Energy / Input Energy
b) (Output Energy / Input Energy) x 100
c) Useful heat / Total heat
d) (Useful heat / Total heat) x 100
62. Moving iron attraction type meter used for
a) Measure current in A.C
b) Measure current in D.C
c) a & b are correct
d) None of the above
63. Moving coil instrument used in
a) ac only
b) dc only
c) both ac & dc
d) None of the above
64. Fluorescent lamp circuit is a
a) Series Circuit
b) Parallel Circuit
c) Combination of series & Parallel Circuit
d) None of the above
65. In Fluorescent lamp circuit why choke is used
a) it gives low Voltage impulse for starting lamp
b) It gives high Voltage impulse for starting lamp
c) It prevent the lamp from overvoltages
d) it acts as a stabillizer
66. Alternators are rated in
a) KW b) KVA
c) KVAR
d) None of the above
67. The inverse of reluctance is called
a) Permence
b) Permittance
c) Saturation
d) None of the above
68 . Ci rcul ati ng current protect on scheme used i n
a) busbar Answer
b) Transformer
c) Feeder
d) None of the above
69. Ti me -graded protecti on scheme used i n
a) busbar
b) Transformer
c) Feeder Answer
d) Transmi ssi on l i ne
70. Carri er current protecti on scheme used i n
a) Busbar
b) Transformer
c) Feeder Answer
d) Reactor
71. FET i s a
a) Bi pol ar devi ce
b) Uni pol ar devi ceAnswer
c) Curent Control l ed devi ce
d) None of the above
72. BJT i s a
a) Uni pol ar devi ce
b) Vol tage control l ed devi ce-
c) Bi pol ar devi ce -Answer
d) None of the above
73. Current carri er hol es are el ectrons for
a) N Channel JFET -Answer
b) P Channel JFET
c) a & b are correct
d) None of the above
74. I n Enhancement mode the MOSFET operates when
a) Gate vol tage i s negati ve
b) Drai n vol tage i s negati ve
c) Source Vol tage i s posi ti ve
d) Gate vol tage i s posi ti ve-Answer
75. MOSFET operates i n
a) onl y i n enhancement method
b) onl y i n depl eti on method
c) a and b are correct-Answer
d) None of the above
76. Power MOSFET i s a
a) Current control l ed devi ce
b) Vol tage control l ed devi ce-Answer
c) a & b are correct
d) none of the above
77. FET i s a
a) Bi pol ar devi ce
b) Current control l ed devi ce-Answer
c)Three termi nal semi conductor devi ce
d) none of the above
78 . Zener di ode i s a
a) Vol tage regul ator di ode
b) Breakdown di ode
c) Current regul ator di ode-Answer
d) a and b are correct
79. Epi taxi al growth method used i n
a) I C Fabri cati on -Answer
b) MOSFET Fabri cati on
c) BJT Fabri cati on
d) None of the above
80Di stance Rel ays operates when
a) The rati o V/I i s l ess than a predetermi ned val ue-Answer
b) The rati o V/I i s hi gher than a predetermi ned
c) a and b are correct
d) None of the above
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