| Post Name | Electrician / Overseer Gr-I / Junior Instructor 040/2023 |
|---|---|
| Question Paper Code | 129/2024 |
| Category Code | 040/2023, 252/2023, 672/2023 |
| Date of Test | 30 September 2024 |
| Medium of Question | ENGLISH |
| Exam Type | OMR Examination |
| Total Questions | 100 |
1
Under which of the following circumstances current flow through an electric circuit is
possible?
(i) If the circuit is in closed condition
(ii) If sufficient voltage drop is available
Answer
A. (i) only
2
Commercial unit of electrical energy is :
Answer
A. Kilowatt-hour
3
In an electric circuit at constant temperature the relationship between current, voltage
and resistance is given by :
Answer
B. Ohm's law
4
Two bulbs 200 Watts and 100 Watts both rated at 100 V are connected in series to a
200 volts dc supply. Total power consumed by this circuit is ββββββββββ Watts.
Answer
D. 266.67
5
N number of resistances each of value R are connected in parallel. When these
resistances are connected in series, equivalent resistance is increased by ββββββββββ
times.
Answer
C. NΒ²
6
A wire by resistance of R ohms is stretched such that its length becomes double keeping
the volume same. The new resistance will be ββββββββββ Ohms.
Answer
D. 4R
7
Which of the following properties does not hold good for a series circuit?
Answer
A. Currents are additive
8
50 numbers of dry cells each having 1.5 V and internal resistance of 0.2 Ξ© are connected
in series across a 40 Ξ© resistor. Calculate the current through the resistor :
Answer
B. 1.5 A
9
A resistor of 10 Ξ© is connected in series with a combination of 60 Ξ© and 30 Ξ© in
parallel. A voltage of 220 V is applied across the whole circuit. Determine the current
taken from the supply :
Answer
A. 7.33 A
10
Which one of the following lamps has the lowest resistance?
(i) 220 V 40 W
(ii) 220 V 60 W
(iii) 220 V 100 W
(iv) 220 V 200 W
Answer
D. 220 V 200 W
11
Work done in moving a unit positive charge from infinity to a point is called :
Answer
B. Potential
12
The term analogous to electric current in magnetic circuit is :
Answer
C. Flux
13
Direction of induced current in a coil rotating in a magnetic field can be determined by :
Answer
C. Flemings right hand rule
14
If three different capacitors are connected in series to a dc supply, the greater voltage
will appear across the capacitor having ββββββββββ capacitance.
Answer
B. Smallest
15
Three equal capacitors are provided. In which of the following combinations least
equivalent capacitance value will be obtained?
Answer
A. When all in series
16
As per Flemings left hand rule fore finger indicates the direction of :
Answer
D. Magnetic field
17
Two coils of inductance L1 and L2 are placed adjacent to each other such that magnetic
flux in coil 1 completely links with coil 2. The mutual inductance between the coils is :
Answer
A. L1 L2
18
Which one of the following components will oppose changes in current through the
circuit?
Answer
B. Inductance
19
Three capacitors having capacitances 2F, 3F, 4F respectively are connected in series and
in parallel. Calculate the equivalent capacitance for each combinations :
Answer
C. 0.923F in series and 9F in parallel
20
It is found that when the current through an inductive coil decreases from 8A to zero in
0.4 seconds, a 40 V emf is induced in it. The inductance of the choke coil is ββββββββββ
Henry.
Answer
D. 2
21
Two sinusoidal currents are iβ = 30 sin(Οt + Ο/3) and iβ = 50 sin(Οt β Ο/4). Their phase difference is
Answer
A. 105 degrees
22
An AC supply of frequency 50 Hz is connected to a capacitor offered a reactance of 10 Ξ©.
If the frequency is increased to 100 Hz reactance become :
Answer
B. 5Ξ©
23
In a parallel resistance inductance (RL) circuit, if I R is the current in the resistor and
I L is the current in the inductor, then :
Answer
D. I L lag I R by 90 degrees
24
In an AC series circuit, higher Q factor indicate :
Answer
B. Sharper its resonance
25
The symbol βjβ represents counterclockwise rotation vector through :
Answer
B. 90 degrees
26
The phase sequence of a three phase is reversed to the three phase load, then :
Answer
C. Phase currents changed in angle but not in magnitude
27
The main problem occur in a low power factor circuit is :
Answer
Question Cancelled
28
For the same rating, the size of a three phase motor will be :
Answer
A. Less in size
29
Three resisters are connected in delta and three phase supply given to that circuit then
one resistor is open, power will be :
Answer
B. Reduced by 1/3
30
If the B phase of a three phase star connected alternator become reverse connected by
mistake, it will not affect :
Answer
B. VRY
31
The meter that is suitable only for direct current measurement is :
Answer
C. Permanent magnet type
32
The damping torque acts on the moving system of an indicating instrument only when
it is :
Answer
Question Cancelled
33
The full scale deflection current of a moving coil instrument is about :
Answer
A. 50 mA
34
Maxwell β Wein Bridge is used for measuring :
Answer
C. Inductance
35
The main purpose of an instrument transformer use in ac measurement is :
Answer
C. Extend the range of an instrument
36
A 10 MHZ CRO has :
Answer
D. 10 MHZ horizontal oscillator
37
The two pressure coils of a single phase power factor meter have :
Answer
A. The same dimensions and the same number of turns
38
An insulation megger is usually :
Answer
D. Moving coil type instrument
39
Which instrument is most suitable for the measurement of 10 mV at 50 MHz?
Answer
C. CRO
40
Output of a digital multimeter is :
Answer
D. Electrical quantity
41
Which is the best fire extinguisher used for subsiding the fire on electrical equipment?
Answer
A. Liquid carbon dioxide
42
Which of the following is not a first aid treatment for an electric shock?
Answer
D. Give water to the victim to drink
43
The rated voltage of a standard lead-acid cell :
Answer
C. 2 volts
44
Battery capacity depends on :
Answer
D. all of the above
45
The most common type of rechargeable battery used in electric vehicles :
Answer
C. lithium-ion battery
46
Which of the following material is used for making solar cell?
Answer
D. Silicon
47
Solar cell converts light energy in to :
Answer
B. electrical energy
48
Which of the following device is having least tripping current?
Answer
B. ELCB
49
A typical output of a single junction silicon solar cell is βββββββ volt.
Answer
A. 0.6
50
A safety device is used in an electric circuit for protecting the :
Answer
D. All of the above
51
The purpose of an electric circuit breaker is :
Answer
B. to protect an individual electrical circuit from excessive current flow
52
Resistance of a wire is directly proportional to its :
Answer
B. length
53
The reciprocal of resistivity is known as :
Answer
C. conductivity
54
Which of the following can use as a star-delta starter?
Answer
D. TPDT
55
Candela is the unit of :
Answer
C. luminous intensity
56
βββββββ is used as filament in the incandescent lamps.
Answer
A. Tungsten
57
The rewireable fuses are standardized for rated current up to βββββββ Ampere.
Answer
B. 200
58
The ratio of illumination under normal working condition to the illumination when
everything is clean is known as
Answer
A. Depreciation factor
59
Which type of earthing is preferred at places where soil is rocky with a earth bed over it?
Answer
C. Strip earthing
60
The initial colour of a sodium vapour lamp when it is switched on :
Answer
A. Pink
61
The greatest eddy current loss occurs in βββββββ of d.c machine.
Answer
D. armature poles
62
In which of the following method the supply voltage to the separately excited d.c motor is
revered?
Answer
D. Forward plugging
63
The rheostatic speed control method of d.c machine is very :
Answer
C. unsuitable for rapidly changing loads
64
The armature of a d.c machine having 10 poles is rotating at a speed of 10 revolutions
per second. The number of hysteresis loops formed per second is :
Answer
D. 50
65
Which of the following DC motors can run on zero speed regulation even at loaded
condition?
Answer
B. Differential compound motor
66
The type of d.c generator for arc welding is :
Answer
D. Differentially compound
67
The line representing the critical resistance of a d.c generator βββββββ its O.C.C.
Answer
C. just touches
68
If P is the number of poles of a generator and N is the armature speed in rpm, the frequency f of magnetic reversal is
Answer
A. f = NP/120
69
Swinburneβs test cannot be performed on which of the following motors?
Answer
B. Series DC motor
70
The torque-speed characteristics of a d.c shunt motor is :
Answer
B. a drooping straight line
71
The starting torque of 3 phase induction motor is βββββββ supply voltage.
Answer
C. directly proportional to square of
72
Auto Transformer can do the following :
Answer
C. Both
73
The maximum value of torque angle of synchronous motor is :
Answer
B. 90ΒΊ
74
When an induction motor is running at full load rotor reactance is ββββββββββ rotor
resistance.
Answer
A. Comparable to
75
Which type of alternator used is used in hydroelectric power station?
Answer
D. Salient pole
76
All day efficiency is meant to judge the performance of a transformer :
Answer
A. Distribution
77
A 10kVA, 230/1000 V single phase transformer the no load current will be about :
Answer
Question Cancelled
78
A transformer transforms :
Answer
Question Cancelled
79
At leading power factor, the armature flux in an alternator :
Answer
B. Aids the rotor flux
80
A transformer has full load copper loss of 400 W. The copper loss of at half full load will
be :
Answer
A. 100 W
81
Which of the following flip flop is not free from race around condition?
Answer
Question Cancelled
82
The given flip flop was initially cleared and then clocked for 5 pulses, the sequence at Q
will be (including the initial pulse) :
Answer
D. 01010
83
The group of bits 10010 is serially shifted (LSB first) into a 5 bit parallel output right
shift register with an initial state 10100. After 3 clock pulses, the register contains :
Answer
B. 01010
84
An 8 bit DAC produces an output of 0.05V for a digital input of 00000001. The full scale
output voltage is nearly :
Answer
B. 12.8
85
The minimum number of NAND gates used to realize Y = A + ABβ² + ABβ²C is
Answer
C. 0
86
The counter having most speed is :
Answer
Question Cancelled
87
A 4 bit parallel adder circuit is to be implemented. For this the number of half adders
and OR gates required if there is no initial carry is :
Answer
B. 7 half adders and 3 OR gates
88
The number of comparators in a 4 bit flash ADC is :
Answer
D. 15
89
The diagram shows two cross-coupled NOR gates, with x entering the upper gate whose output is A and y entering the lower gate whose output is B. If x = 1 and y = 1 initially, and then y is replaced by the sequence 101, the outputs A and B are
Answer
D. A = 0 and B = 010
90
The main purpose of flux in soldering is to :
Answer
C. Keep the metal surface clean and oxide free
91
On comparing Centre tap and Full wave bridge rectifiers, the dominant advantage of
bridge rectifiers is :
Answer
D. Lower peak inverse requirement for the diode
92
A JFET, when properly biased act as, :
Answer
D. Voltage controlled current source
A 13 129/2024
93
In a JFET, after VPS reaches pinch-off value VP , drain current S D becomes, :
Answer
Question Cancelled
94
A DIAC is equivalent to :
Answer
Question Cancelled
95
A TRIAC can be triggered into conduction by :
Answer
B. Positive or negative voltage at either gate
96
The structure of IGBT is :
Answer
Question Cancelled
97
Snubber circuit is used to :
Answer
B. Limit the rate of rise of voltage across SCR
98
The intrinsic stand-off ratio of a UJT can be :
Answer
C. 0.7
99
Larger the value of filter capacitor :
Answer
B. Larger will be the value of peak current in the rectifying diode
100
Which of the following part makes an online UPS different from offline UPS?
Answer
Question Cancelled
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