26. A technique of encoding and decoding messages is called

Lithography Cartography


Cryptography Seismography


27. The main object of the 'Curiosity Rover' that landed on Mars on 6th August, 2012, was to

search signs of existence of living organisms


search places of water


collect samples of minerals, elements


establish communication system


28. Which of the following gases is not responsible for air pollution?

Nitrogen Carbon dioxide


Sulphur dioxide Hydrogen sulphide


29. Which of the following is used as a in rockets?

Liquid ammonia Liquid carbon dioxide


Solid carbon dioxide Liquid oxygen


30. India's largest 9900 MW-.Jaitapur (Ratnagiri) nuclear power plant will be set up in collaboration with
France .Japan Germany Switzerland
31. Which of the following is correct about the phenomenon of 'capillary action' Ignition of kerosene lamp, Working of blotting paper.
c.
Existence and growth of tall trees.

d.
Drinking of soft drink by straw.
Answer options




Only a and b Only a. band d


Onlya, bandc Alla,b,c andd


32. India's heaviest Satellite, GSAT-10, was launched from Kourou. F!,ench Guiana, to boost telecommunication and DTH broadcasting on

September 19, 2012 September 2012


September 29, 2012 September 21, 2012


1lffim JIITIT SPACE FOR ROUGH WORK
A 7
33. Who postulated the Special Theory of Relativity?

Darwin Newton


Einstein Galileo


34. The chemical acids and bases neutralize each other to form

salt and water salt and gas


gas and water only salt


35. Adding salt and sugar to food substances helps in preserving them for a longer duration. It is because excess salt and sugar

plasmolyse the microbial cells


cause rupturing of microbial cells


cause changes in the shape of microbial cells


remove water directly from food substances


36. Which one of the following is included in the World List of Biosphere Reserves by UNESCO?

Kinnaur Region Spiti Valley


Nallamalai Hills Sunderbans


37. Which of the following is not an insecticide?
D.D.T. Potash alum Endrin Folidol
38. Match the following:
a.
Barometer I. Light

b.
Thermometer II. Pressure

c.
Lux meter III. Current

d.
Ammeter IV. Temperature


abc d

IV II III I


II IV I III



IV II I III


II IVIII I


il5w:rr <l>I'lI·tll61 JlTlT1 I SPACE FOR ROUGH WORK
P.T.D.

001 8 A
39. Bats can fly at night because their wings generate

Ultraviolet rays Radio waves


Ultrasonic waves Intrasonic waves


40. The thumb of human hand moves more freely than other fingers due to

Pivotal joint Gliding joint


Hinge joint Saddle joint


41. Nanotechnology is the term used for study of objects having size

1 -100 nanometers


1 -10 micrometers


more than 100 nanometers


less than one micrometer


42. Diamond and Graphite are polymorphs of the element carbon. Which of the following is correct about Diamond and Graphite?
a.
Diamond is hard. Graphite is soft.

b.
Diamond and Graphite. both are electrical insulators.

c.
Diamond is transparent. Graphite is opaque.

d.
Diamond is the ultimate abrasive, Graphite is a good lubricant.
Answer options




Only a and b Only a. band c


Onlya.c andd Alla, b.candd


43. Identify the following element group, which is responsible for production of living organisms on the Earth

Hydrogen, Oxygen, Sodium


Carbon, Hydrogen, Nitrogen


Oxygen, Calcium, Phosphorus


Carbon, Hydrogen, Potassium


JI11IT I SPACE FOR ROUGH WORK
A 9 001
44. ARTI is an institute associated with Industrial Development Urban Development Rural Technology Road Development

45. Which of the following is not an allotrope of carbon

Fullerene Carbon Nanotube


Diamond Benzene


46. The direction of magnetic field around a straight conductor carrying current is given by

The Right Hand Rule Fleming's Left Hand Rule


Fleming's Right Hand Rule None of these


47. Atoms and molecules follow laws formulated by which of the following theories?

Quantum Mechanics Celestial Mechanics


Thermodynamics Theory of Relativity


48. The output device of computer is

Motherboard


Central Processing Unit


Keyboard


Monitor


49. The DNA in our body cell has which of the following structures?

Spherical Spiral


Ring-like Double helix


50. The mobile phones which run on solar energy were first manufactured by

Samsung Nokia


Motorola Reliance


CIffiZn Jl1TII I SPACE FOR ROUGH WORK

P.T.O.
a0110 A
51. The current drawn by a 120 V d.c. motor having armature resistance of 0·5 nand back e.m.[ 110 V is
240 Amp 20 Amp 220 Amp 05 Amp
52. Choose the correct answer A moving coil type instrument can be modified to measure voltages by

using thicker wire in the coil.


using a high resistance shunt.


adding resistance in series.


adding resistance in parallel.


53. The moving coil in a dynamometer wattmeter is connected

in series with the fixed coil


across the supply


in series with the load


across the load


54. Which of the following motors is usually used in household refrigeration?
a.
Reluctance motor

b.
Synchronous motor

c.
Single phase induction motor

d.
3-phase induction motor
Answer options




a only b only


c and d only conly


55. Choose correct answer Secondary output voltage of the transformer increases if

Supply frequency of transformer decreases.


Cross-section area of magnetic core of a transformer increases.


Flux density of core of transformer decreases.


Secondary number of turns in a transformer decreases.


Cl)W:IT (wlI;elc51 JIITTT SPACE FOR ROUGH WORK

A 11 n01
56. Two transformers of different kVA rating working in parallel, share the load in proportion to their rating when their

per unit leakage impedance on the same kVA base is the same


per unit leakage impedance on their respective rating is equal


ohmic values of the leakage impedance are inversely proportional to their ratmg


ohmic values of the magnetizing reactances are same


57. The resistance and reactance of a 100 kVA, 11000/400 distribution transformer are 0·02 and 0·07 pu respectively. The phase impedance of the transformer referred to the primary is

(0·02 jl-925) n


(15·125 j52·94) (72·6 j254'1l


58. The equivalent circuit of a transformer has leakage reactance and magnetizing reactance X . Their magnitude must satisfy
m
Xl» X Xl «
m

59. Match the following:
a. Core loss of a transformer I. depends on input voltage
b. c. Efficiency of a transformer Secondary output voltage of a transformer II. III. depends on maximum flux density in the core depends on load
d. The number of primary turns of a transformer IV. depends on power factor
a b c d
I II IV III II I III II III IV II I IV III I IV
..--­llffilIT ibi'litll61 Jll'TT I SPACE FOR ROUGH WORK P.T.O.

001 12 A
60. Choose the correct anSwer A synchronous machine can operate

only as a generator only as a motor


Both as generator and as motor None of the above


61. Four point starter on G..c. motor is used
a.
to increase field current.

b.
to decrease fie ld current.

c.
to protect no volt coil.

d.
not to affect field current passing through field on coil even if any change takes place in field current.


Answer options

a and b only b only


d only All of the above


62. A sinusoidal voltage of frequency 1 Hz is applied to the tleld of d.c. generator. The armature voltage will be

1 Hz square wave 1 Hz sinusoidal wave


d.e. voltage wave No EMF generated


63. A good transformer must have high regulation as far as possible. Select the best option.
95-98% 92-94% 90 87
64. What will happen if percentage impedance of two transformers working in parallel is different?
a.
Parallel operation is not possible.

b.
Two transformers will operate at different power factor than common load.

c.
Transformers will be overloaded.

d.
Power factor will be same for both.
Answer options



a and d only b only c and d only conly
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A 13 a01
65. Match the following
a. I.Silicon steel used in transformer core To reduce eddy current loss
b. Transformer core is laminated II. To reduce hysterisis loss
c. d. The iron core in a transformer Cooling of transformer is required III. To dissipate the heat generated in the winding IV. Provides low reluctance path to the main flux
a b c d
I II III IV
II I III IV
I II IV III
II I IV III

66. Choose correct answer At a certain speed and flux, the voltage generated by a d.c. generator is 230 volts. If
the speed is increased by 20% and the flux is simultaneously reduced by the voltage will be
increased by 10% reduced by 20% increased by decreased by
67. A 4 pole generator with 16 coils has a two layer lap winding. The pole pitch is
32 16 8
68. Synchronous motor having its field winding shorted on themselves placed III a cylindrical rotor will

not start


start but not run at synchronous speed


start as an induction motor and then run as synchronous motor


start and run as a synchronous motor


69. A synchronous generator connected to an infinite bus is overexcited. Considering only the reactive power, from the point of view of the system, the machine acts as

capacitor inductor


resistor None of the above


1lffiOZlT d51l't1'tl161 JIIlTT I SPACE FOR ROUGH WORK
p.T.a.
00114 A
70. No-load test on a 3-phase induction motor was conducted at different supply voltages and a plot of input power versus voltage was drawn. This curve was extrapolated to intersect the Y-axis. This intersection point is

core loss stator copper loss


stray load loss friction and windage loss


71. Which of the following statements is false?

Zero power factor method of an alternator is used Lo find its voltage regulation.


The frequency of voltage generated by an alternator having four poles and rotating at 1800 r.p.m. is 60 Hz.


At lagging loads, armature reaction in an alternator is cross magnetizing.


With a unity load p.f., the effect of armature reaetion on the main field flux of an alternator is distortional.


72. In induction machines, which of the following statements is true?

When rotor is at standstill slip is one.


When the motor runs at synchronous speed slip is zero.


Frequency of current in rotor is known as slip frequency.


All the above statements are true


73. If the iron loss and full load Cu losses are given, then the load at which two losses
would be equal is given by
Iron loss (Iron loss)2

a. Full load x b. Full load
Cu loss y Cu loss
Iron loss
c. Full load x d. Full load x






eu loss

Answer options
a c cand d b
74. When a bank of two single phase transformers in open delta arrangement is used, each of them supplies
a.
33·3% of its output rating b. 66·6% of its output rating

c.
48·6% of its output rating d. 100% of its output rating
Answer options




a only conly


b only None of the above



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A 15 001
75. In a four pole d.c. machine alternate poles are north and south two north poles follow two south poles all the four poles are south poles all the four poles are north poles
76. Form factor is defined by

K r.m.s. value K r.m.s. value

f -Average value f Maximum value
K Average value None of the above
f-Peak value

77. The magnetic strength is inversely proportional to the distance from the conductor in which current flows. This law is known as
a.
Lenzlaw b. Biot law

c.
Biot-Savart law d. Ampere's law
Answer options




c and d only conly


a only b only



78. The injected e.m.f. in the rotor of induction motor must have

low frequency


same frequency as the slip frequency


same phase as the rotor e.m.f.


All of the above



79. The induction motor is started using the methods given below to reduce the current during start.

Direct on line starting Star-Delta starting


Autotransformer starting Both and



80. A voltmeter using 50 micro ampere meter movement has a sensitivity of
a.
500 ohm per volt b. 5000 ohm per volt

c.
2000 ohm per volt d. 20,000 ohm per volt


Answer options
a only b only c and d only d only <l51l11'fl16l JlIl11 SPACE FOR ROUGH WORK
P.T.D.

001 16 A
81. The main type of failure in wind power generating plant is in

electrical system mechanical system


aerodynamic system both and


82. The basic requirements of surge diverter or surge arrester arc
a.
break down as quickly as possible when the abnormal voltage arrives.

b.
pass no current at normal voltage.

c.
interrupt the power frequency follow on current after nash over.

d.
pass large current on arrival of abnormal voltage.
Identify correct requirements.
Answer options




band d c and d


a,bandc b,c andd


83. Time-Of-Day (TOm tariffs are said to be effective in
a.
reducing the maximum demand.

b.
reducing the harmonics.

c.
reducing the commercial losses.

d.
increasing the revenue of the utility.
Which of the above optionls is/are correct



a only band conly d only a and b only
84. Sheaths are used in power cables in order to

increase the strength of the cable


prevent moisture from entering the cable


provide adequate insulation


None of the above


85. Corona loss is reduced by using hollow conductors because of
a.
better ventilation. b. eddy current elimination.

c.
flux density reduction. d. increased radius of the conductor. Which of the optionls is/are correct


a and b only b only conly d only
lIlttZlT ,f)IIiI'ttl6'l I SPACE FOR ROUGH WORK

A 17
86. Auto reclosing circuit breakers improve stability as these breakers
a.
open when fault is detected and auto reclose after set time.

b.
reopen and reclose again if fault persists as before.

c.
one more trial of reopen and reclose is carried out.

d.
if the fault still persists, the breaker remains closed.


Pick correct option
Answer options:

a only a and b only (31 band c a and d only
87. A fuel cell converts chemical energy into electricity. The positive and negative electrodes are supplied respectively with
oxygen and hydrogen (21 oxygen and uiLrogen
(31 nitrogen and hydrogen nitrogen and oxygen

88. A distance relay measures

current difference voltage difference


impedance difference (41 distance between lwo


89. For very large capacity turbo alternators in thermal power plants. hydrogen cooling is desirable as it allows
a.
lower windage losses.

b.
increase in life of insulation.

c.
avoidance of fire hazard in machine.

d.
for same frame size, increased power output.
Which is the correct option?




andd 12) a,bandc


band d None of the above


90. In high head hydro power stations a surge tank is provided in order to
a.
allow constant storage of specitic quantity of water.

b.
reduce the water hammer efrect.

c.
avoid creation of vacuum in the water system.

d.
help stabilize water velocity and pressure in penstock.
Answer options




a only b only


band conly c and d



Q5Jill'lfl6) JlTlTT I SPACE FOR ROUGH WORK
P.T.O.
001 18 A
91. Klydonograph when used for measurement of voltages provides information on

magnitude and polarity polarity and frequency


magnitude and frequency all the above


92. The load t10w solution is always assured in case of

Gauss method


Gauss -Seidel method


Newton --Raphson method


None of these methods guarantees


93. Voltage control of a power transmission line is achieved by

tap-changing transformer booster transformer


injection of reactive power All the above


94. According to the provisions of the Electricity Act 2003, undue preference shall not be shown to any consumer of electricity in the determination of tariff, but consumers may be differentiated according to the
a.
voltage, power factor, load factor.

b.
geographical location or purpose of supply or total consumption during specific period.

c.
nature of supply and the purpose for which supply is required.

d.
category of economically weaker section or BPL (Below Poverty Line) family. Answer options



d only band conly


band conly a and d only


95. For a long distance transmission line under no load condition, if Vsand Vr are the sending end and the receiving end voltages respectively. then
V V=V
rs sr r
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A 19
96. In large coal based thermal power plants most efficient and widely used dust and ash collection is through ESP (Electro Static Precipitator) because
a.
it can remove dust particles even upto 0·01 micron.

b.
it allows reduction in LD. Fan ratings.

c.
dust collection is in dry form and can be easily removed.

d.
it is relatively cheaper than mechanical separators.


Identify the correct reasons.
Answer options


a,c andd b,candd


a,bandc a,d andb


97. The overall efficiency of thermal power station is low mainly due to low efficiency of

Alternator Boiler


Steam turbine and condenser Non-salient pole or cylindrical rotor


98. A thermal power station has an overall efficiency of 30 percent. For generating 1 kWh of electrical energy, 0·5 kg of coal is burnt, If heat equivalent of 1 kWh is 900 kcal, then the calorific value of the fuel is

6000 kcallkg 54000 kcallkg


13500 kcallkg 4500 kcallkg


99. In substations cheaper form of switches known as isolators are used in conjunction with high voltage equipments. These isolators
a.
can close live circuits. b, can open live circuits.

c.
cannot close live circuits, d. cannot open live circuits,


Which of these are true? Answer options
aandd aandb bandc candd
lIffi:IU JITII1 I SPACE FOR ROUGH WORK
p.T.a,



n01 20 A
100. In nuclear reactor, energy produced by fission reaction of Uranium, U-235 having
mass of atom and velocity of light is given by 2 12 1 2
mc mc -mc mc 22
101. Which of the following circuit breakers has the lowest operating voltage? SF6 gas Air break Air blast Minimum oil

102. Of the following factors which one should ideally be equal to ]·0
a.
Demand factor b. Load factor

c.
Diversity factor d. Plant use factor
Answer options:



b bandd a,bandd a,c andd


103. The following condition causes transient instability in power system:

Short circuit


Loss of excitation in a generator


Switching operations on the line


All of the above


104. Sub-stations which receive power at some voltage and deliver it at some other voltage are called as

Converting sub-stations Switching sub-stations


Transformer sub·stations Delivery sub-stations


105. Pumped storage hydro plants are peculiar in the sense that these
a.
operate as a power sink during off peak hours.

b.
operate as a power source during peak hours.

c.
restrict the flexibility in schedule of operation.

d.
improve the load factor of the overall plant.
Identify the correct statements.
Answer options




a and b only band c


c and d only band d



CIffiZlT JITTIT I SPACE FOR ROUGH WORK
A 21 n01
106.
In a SCADA system, interface between sub-station and remote control centre is made

107.
What advantages does the output module of PLC using solid state switching elements have?

a.
Fast switching speed b. Overload restrictions

c.
No contact arcing d. No switching noise

e.
Possibility of false tripping Answer options



a,c andd b,d ande


c and e All of the above




VIa:
a. Remote Terminal Unit
b. PC with microwave link
c. PC with fibre optic link
d. PC with telephone line link
Answer options
a only band conly
c and d only band conly


108. Fibre-optic communication for relaying is used nowadays because
a.
It is complete dielectric, not affected by ground loops, not affected by inductive pick-up and lightning and less losses.

b.
It is semi-dielectric, not affected by lightning, small and light in weight.

c.
It is small and light in weight with high bandwidth.

d.
It is complete dielectric and not affected by inductive pick-up, but affected by lightning.


Answer options

a only (21 a and b only


a and conly a and d only


109. Out of the following, which is/are not a binary I/O device/devices
a.
Alarm Bell b. Thermocouple

c.
Proximity Switch d. Tachogenerator

e.
Indicating Lamp Answer options


a only band d only c and e c and e

dWHtll61 JII1IT I SPACE FOR ROUGH WORK
p.T.a.
001 22 A
110. Advantages of distance relay over current relay is/are
a.
Fixed zone of protection, independent of system changes, requiring less setting maintenance.

b.
Lower impedance of load.

c.
Lower sensitivity.

d.
Lower instantaneous trip coverage.
Answer options




a and b only


a only


c and d only


c and d only


111. A x converter located in an output module of a controller may convert ---.L-signal into 4 rnA to 20 rnA range.
a. DtoA b. AtoD c. Analog d. Digital Answer options









112. Main components used for analog to digital conversion are
a. Buffer amplifier and low pass filter b. Sample and hold unit
AID converter and sensor Rectifier and multiplexer
Answer options


aandbonly b,c anddonly


band conly c and d only


113. The difficulties associated with differential protection are Difference in length of pilot wires Relay operating time C,T. Ratio errors Saturation of magnetic circuit Answer options

a,c andd a,bandc.


c and d All of the above



d51'l1'lt161 JlTl11 SPACE FOR ROUGH WORK
A 23 a01
114. Buchholz relay is an example of

Electrodynamic type relay Physico-electric relay


Moving coil type relay Static relay


115. Type testis conducted as short circuit testis on circuit breaker are
a.
making capacity test b. breaking capacity test

c.
temperature rise test d. one minute dry withstand test Answer options:


a b a and b c and d
116.
In lin oil circuit breaker, the heat generated decomposes the oil and following gases

117.
Which of the following relay/relays is/are not required for protection of a transformer

a.
Over Load (Relay) b. Buchholz (Relay)

c.
Distance (Relay) d. Rotor Fault Protection (Relay) Answer options


aandb c and d c and d d

118.
Static relays are commonly used for

a.
EHV lines b. UHV lines

c.
LV distribution d. HV distribution Answer options:


a b
aandb c and d

119.
A.C. rating of a C.B. is 200 A and 500 V. Its D.C. rating will be


200 500 V less than 200 500 V


more than 200 500 V more than 200 1000 V




are liberated:
a. Hydrogen b. Acetylene c. Methane d. Oxygen
Answer options
c and d only band conly
band conly a only

dJlill'lti61 JITlTT SPACE FOR ROUGH WORK
P.T.O.
24 A
120. Commonly used A/D converters is/are
a.
ramp converter

b.
successive approximation converter

c.
ramp and successive approximation simultaneously

d.
ramp and successive approximation alternately Answer options



a only b only


a and b only c and d only


121. Identify the incorrect statement

Circuit breaker carries rated current without any damage.


Circuit breaker opens and closes the circuit only on no-load.


Circuit breaker carries rated current without overheating of components.


Circuit breaker is capable of carrying short circuit current lor a very short time.


122. For a SCADA system operating at a low rate data communication system, instruction's signal communication is from
RTU to RTU RTU to MTU
CPU to MTU MTU to RTU
123.
Transducers in the remote units of SCADA system are used to convert following quantities to direct current or voltage form

124.
Distance relay may be of following type

a.
Offset and Restricted relay b. Reactance relay

c.
Admittance relay d. Percentage differential relay Answer options



band d only c and d only


band conly c and d



125.
In a carrier system, drift and spurious signals are important because


they modulate the carrier


they do not modulate the carrier


it is easier to achieve a stable carrier than a stabilized d.c. source


None of the above




a. Voltage b. Current c. Watts d. VARs
Answer options
a b 14) a. b. c and d


<tl1¥Jltll61 ;;rrrrr SPACE FOR ROUGH WORK
A 25 aD1
126. The desirable properties of earth mat used in power systems include

high dielectric strength and low insulation resistance


low dielectric strength and high insulation resistance


high dielectric strength and high insulation resistance


low dielectric strength and low insulation resistance


127. If the speed of a centrifugal pump is doubled, its power consumption increases times.
3 no change
128. The operating point in a pumping system is identified by

cannot be determined by the pump characteristics curve


point of intersection of pump curve and theoretical power curve


point of intersection of pump curve and system curve


point of intersection of system curve and efficiency curve


129. All power stations and sub-stations need d.c. supply for which purpose?

Generation and protection Protection and control


Control and generation Generation, protection and control


130. For a lead-acid battery, if llAH and llWH denote ampere-hour efficiency and watt-hour efficiency, then the following statement is true?

llAH llWH always


llAH llWH always


both llAH and llWH are nearly equal


their values depend on the application


131. The moving part of a centrifugal pump is called a

Diffuser Suction Nozzle


Volute Impeller


132. What geometrical shape does charging characteristic of a battery follow?

Straight line Exponential curve


Ellipse None of the above


133. What will a small portable green coloured fire extinguisher contain
Carbon dioxide Halon gas
Purple K dry powder Foam

"'1111'616 JIITlT I SPACE FOR ROUGH WORK P.T.D.






001 26 A
134. Internal resistance of primary cell varies

inversely with the surface area of electrodes


directly with the distance between electrodes


with the nature of electrodes


All of the above


135. Resistivity of earth is normally
200 a-m 100 a-m 50 a-m 400 a-m
136. The following is the only electronically synthesized high quality power source.

AC Mains Diesel Generator


UPS None of the above


137. The magnitude of 'let go current' adopted in calculating maximum permissible step and touch potentials (as per IEEE-80-1976) for man is
6 rnA 9 rnA 9A 9,v
138. What is the basic requirement of an electric motor to be employed in lift applications?

High running torque Low running torque


High starting torque High starting current


139. The earth resistance of power stations shall be

upto 50 a more than 0·5 a


more than 5 a less than 0·5 n


140. Which cell has the reversible chemical reaction?

Lead acid Mercury oxide


Carbon zinc Silver oxide


141. The term "B" (Bend of useful life) for a UPS battery refers to the fact that these batteries

do not require fluid require fluid


require specific fluid require any fluid


142. Open circuit voltage of a fully charged lead acid cell is
1·9 V 2·0 V 2·7 V 2·5 V
143. Ni-Cd batteries do not emit

Hydrogen gas Oxygen gas


Hydrogen and oxygen gas Corrosive gas


JlllTT I SPACE FOR ROUGH WORK
A 27
144. The indication of the state of charge of a battery is best given by

specific gravity of electrolyte temperature of electrolyte


colour of electrolyte level of electrolyte


145. The primary determinant of the voltage developed by a battery is

the nature of the materials in the reaction


the size of the electrodes


the overall size of the galvanic cells


the age of the battery


146. Chopper control for d.c. motor provides variation in

input voltage frequency


current (41 None of the above


147. In a GTO, anode current begins to fall when gate current

is negative peak at time t 0


is negative peak at time t t


.s
just begins to become negative at t 0
. None of these

148. For a thyristor shown below, the following statement is true. J J·J
1z 3
Anode Cathode
Gate

All the three junctions are forward biased


J .Jz are forward biased, J 3 is reverse biased


J 1 is forward biased, J and J 3 are reverse biased


z
J 1 and Jz are reverse biased, J3 is forward biased
149. A step-down chopper is operated in continuous conduction mode in steady state with a constant duty ratio D. If Vo is the magnitude of the d.c. output voltage and if Vs is the magnitude of d.c. input voltage, the ratio vol Vis given by
s
D 1-D
150. In a single phase full-wave a.c. regulator, varying the delay angle a from to 1800 can vary the r.m.s. output voltage from
VstoVs/4 VstoVs/2 Vsto3Vs/2 (41 Vstozero
d5liMlIc5l JlTlIT I SPACE FOR ROUGH WORK
P.T.D.
QOl 28 A
1
fcIf.m! 3fHqGi<JneH W it Cf.11j On'.1 31A m q flIljfW ,Ac;ClIJ.lq{ ilOII=<11 Cf,{O'1Iii1Iii1rlir CH'1<1jf1l{ q q;rm;r of,l'.lqlf1ldll rn TJ:i I fu!
o" l:lR
iG? N(Cfl1Jffi if m 011 0 '1If1 q{qHJn ma:rr 'itIO"li,!cff 3ll'l«""IT 3'i1{QBl&>ill fcHW11 'Cfl"{1it
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