1. If the voltage applied across a capacitance is triangular in waveform then the waveform of the current is-
a) Triangular
b) Trapezoidal
c) Sinusoidal
d) Rectangular
2. One of the following statement which is true for relative dielectric constant is -
a) It is dimensionless
b) It is not equal to unity for vacuum
c) It’s value for all substances is less than one
d) None
3. Pure metals generally have-
a) high conductivity and low temperature coefficient
b) high conductivity and large temperature coefficient
c) low conductivity and zero temperature coefficient
d) low conductivity and high temperature coefficient
4. For small size, high frequency coils, the most common core material is
a) Air
b) Ferrite
c) Powdered ion
d) Steel
5. For an abrupt junction Varactor diode, the dependence of device capacitance (C) on applied reverse bias (V) is given by-
a) C a V1/3
b) C a V-1/3
c) C a V1/2
d) C a V-1/2
6. A superconductor is a-
a) A material showing perfect conductivity and Meissner effect below a critical temperature
b) A conductor having zero resistance
c) A perfect conductor with highest dimagnetic susceptibility
d) A perfect conductor which becomes resistive when the current density through it exceeds a critical value
7. When a semiconductor based temperature transducer has a temperature coefficient of –2500 mV/0C then this transducer is indeed a-
a) Thermistor
b) Forward biased pn junction diode
c) Reverse biased pn junction diode
d) FET
8. The location of lightning arrestor is -
a) Near the transformer
b) Near the circuit breaker
c) Away from the transformer
d) None
9. Time constant of an RC circuit increases if the value of the resistance is -
a) Increased
b) Decreased
c) Neither a nor b
d) Both a and b
10. Intrinsic semiconductors are those which -
a) Are available locally
b) Are made of the semiconductor material in its purest from
c) Have more electrons than holes
d) Have zero energy gaps
11. The primary control on drain current in a JFET is exerted by -
a) Channel resistance
b) Size of depletion regions
c) Voltage drop across channel
d) Gate reverse bias
12. The electrical conductivity of metals which is expressed in ohm-1 m-1 is of the order of -
a) 1010
b) 105
c) 10-4
d) 10-6
13. When biased correctly, a zener diode –
a) acts as a fixed resistance
b) has a constant voltage across it
c) has a constant current passing through it
d) never overheats
14. The current amplification factor adc is given by –
a) IC/IE
b) IC/IB
c) IB/IC
d) IB/IC
15. Compared to bipolars, FETs have-
a) high input impedance
b) low input impedance
c) same input impedance
d) none
16. The source-drain channel of JFET is -
a) ohmic
b) bilateral
c) unilateral
d) both a and b
17. A diac is equivalent to a -
a) Pair of SCRs
b) Pair of four layer SCRs
c) Diode and two resistors
d) Triac width
18. When a sample of N type semiconductor has electron density of 6.25 ´ 1011 /cm3 at 300K and if the intrinsic concentration of carriers in this sample is 2.5 ´ 1013/cm3 then the hole density will be –
a) 106/cm3
b) 103/ cm3
c) 1010/ cm3
d) 1012/ cm3
19. When the two networks shown in fig. are equivalent with respect to the terminals 1 and 2 at all frequencies then the values of CA, LB, LC and CC will be –
a) 0.5, 0.33, 6, 0.166
b) 0.5, 3, 6, 0.66
c) 0.5, 3, 3, 2
d) 0.5, 3, 6, 0.166
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20. The transmission parameter of the network C when the transmission parameter of the network A and B are and respectively are -
21. The statement ‘In any network of linear impedances, the current flowing at any point is equal to the algebraic sum of the currents caused to flow at that point by each of the sources of emf taken separately with all other emf’s reduced to zero’ represents -
a) Kirchhoff’s law
b) Norton’s theorem
c) Thevenin’s theorem
d) Superposition theorem
22. One of the following modes which has the characteristics of attenuation becoming less as the frequency is increased and is attractive at icrowave frequencies of circular cylindrical wave guides is –
a) TE1 mode
b) TM01 mode
c) TE01 mode
d) Higher order mode
23. A two-port network is symmetrical if –
a) z11z22 – z12z21 = 1
b) h11h22 – h12h21 = 1
c) AD – BC = 1
d) y11y22 – y12y21 = 1
24. For transmission line load matching over a range of frequencies, it is best to use a-
a) balun
b) broad band directional coupler
c) double stub
d) single stub of adjustable position
25. The poles and zeros of a driving point function of a network are simple and interlace on the negative real axis with a pole closest to the origin. It can be realised -
a) by an LC network
b) as an RC driving point impedance
c) as an RC driving point admittance
d) only by an RLC network
26. Poles and zeros of a driving point function of a network are simple and interlace on the jw axis. The network consists of elements –
a) R and C
b) L and C
c) R and L
d) R, L and C
27. For a two port reciprocal network, the output open circuit voltage divided by the input current is equal to –
a) B
b) Z12
d) h12
28. In a short electric doublet the radiation properties are so that-
a) The induction field diminishes as the square root of the distance and is only appreciable in the vicinity of the conductor.
b) In the radiation, magnetic field is minimum when the current is maximum.
c) The radiation resistance of a short doublet antenna is extremely high.
d) Mean rate of power through a unit area of spherical sphere surrounding this doublet is proportional to the square of the elemental length, other factors remaining constant.
29. The frequency modulated (FM) radio frequency range is nearly -
a) 250 –300 MHz
b) 150 – 200 MHz
c) 90 – 105 MHz
d) 30-70 MHz
30. In an underground cable the distortion in the transmission of carrier frequency can be eliminated by using -
a) Inductive loading
b) Resistive loading
c) Capacitive loading
d) Shielding
31. The charachteristic impendance of a transmission line with inductance 0.294 mH /m and capacitance 60 pF/m is -
a) 49 W
b) 60 W
c) 70 W
d) 140 W
32. One of the following statements which is not true for a strip line compared to a waveguide is –
a) It can be directly connected to semiconductor microwave devices
b) It is much smaller in size
c) It has a smaller bandwidth
d) Losses are less
33. For a quarter wavelength ideal transmission line of characteristic impedance 50 ohms and load impedance 100 ohms, the input impedance will be –
a) 25W
b) 50W
c) 100W
d) 150W
34. The depth of penetration or skin depth for an electromagnetic field of frequency ‘f’ in a conductor of resistivity r and permeability m is-
a) inversely proportional to r and f and directly proportional to m
b) directly proportional to r and inversely proportional to f and m
c) directly proportional to f and inversely proportional to r and m
d) inversely proportional to r and m and directly proportional to f
35. When an antenna has a gain of 44dB then assuming that the main beam of the antenna is circular in cross-section the beam width will be -
a) 0.4456 0
b) 1.44560
c) 2.44560
d) 3.44560
36. Lens antennas used for microwaves are usually made of -
a) Polystyrene
b) Glass of low refractive index
c) Paraboloid surfaces
d) Dielectric media having large refractive index
37. One of the following types of instrument which is an electrometer is -
a) Electrodynamometer
b) PMMC
c) Electrostatic
d) Moving iron
38. When an ac current of 5A and dc current of 5A flow simultaneously through a circuit then which of the following statement is true ?
a) An ac ammeter will read less than 10A but more than 5A
b) An ac ammeter will read only 5A
c) A dc ammeter will read 10A
d) A dc ammeter will read zero
39. When Q factor of a circuit is high, then -
a) power factor of the circuit is high
b) impedance of the circuit is high
c) bandwidth is large
d) none of these
40. The resolution of a logic analyser is -
a) the maximum number of input channels
b) the minimum duration of the glitch it can capture
c) it’s internal clock period
d) the minimum amplitude of input signal it can display
41. The aperture time of an A to D converter is given by -
42. A memoryless system is –
a) causal
b) not causal
c) nothing can be said
d) none
43. An air capacitor is a –
a) time variant
b) active device
c) time invariant
d) time invariant and passive device
44. Thermistors are made of -
a) pure metals
b) pure insulators
c) sintered mixtures of metallic oxides
d) pure semiconductor
45. Pirani gauge is used to measure –
a) very low pressures
b) high pressures
c) pressures in the region of 1 atm
d) fluid flow
46. These circuits converts input power at one frequency to output power at a different frequency through one stage conversion –
a) AC voltage controllers
b) Cyclo converters
c) Phase controlled rectifiers
d) Inverters
47. In a forward voltage Triggering thyristor changes from –
a) off state to on state
b) on state to off state
c) on state to on state
d) off state to off state
48. Q factor of a coil in Maxwell bridge is obtained as –
49. A thyristor, when triggered, will change from forward blocking state to conduction state if its anode to cathode voltage is equal to -
a) peak repetitive off state forward voltage
b) peak working off state forward voltage
c) peak working off state reverse voltage
d) peak non-repetitive off state forward voltage
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50. Gate characteristic of a thyristor-
a) is a straight line passing through origin
b) is of the type Vg = a + bIg
c) is a curve between Vg and Ig
d) has a spread between two curves of Vg – Ig
51. A four quadrant operation requires-
a) two full converters in series
b) two full converters connected back to back
c) two full converters connected in parallel
d) two semi converters connected back to back
52. If for a single phase half bridge inverter, the amplitude of output voltage is Vs and the output power is P, then their corresponding values for a single phase full bridge inverter are –
a) Vs, P
b) Vs/2, P
c) 2Vs, 2P
d) 2Vs, P
53. For critical damping of the resonant circuit consisting of Rd, L, C in series is –
d) none of the above
54. In an enhancement type MOSFET the output V-I characteristics has –
a) only an ohmic region
b) only a saturation region
c) only ohmic region at 10 W voltage value followed by a saturation region at higher voltages
d) an ohmic region at large voltage values preceded by a saturation region at lower voltages
55. The energy gap in a semiconductor -
a) increases with temperature
b) remains constant
c) slightly increase with temperature
d) decrease with temperature
56. In an electronic circuit matching means -
a) connecting a high impedance directly to low impedance
b) selection of components which are compatible
c) transferring maximum amount of signal between different kinds of circuits.
d) RC coupled stages
57. P channel FETs are less superior than N channel FETs because
a) They have higher input impedance
b) They have high switching time
c) They consume less power
d) Mobility of electrons is greater than that of holes
58. Small increase in temperature in the CE connected transistor is the -
a) Increase in ICEO
b) Increase in ac current gain
c) Decrease in ac current gain
d) Increase in output resistance
59. An amplifier has a band width of 20 KHz and a midband gain of 50 without feedback. If a negative feedback of 1% is applied then bandwidth with feedback is -
a) 13. 3 KHz
b) 30KHz
c) 10KHz
d) 40KHz
60. The output of a class B amplifier -
a) is distortion free
b) consists of positive half cycles only
c) is like the output of a full wave rectifier
d) comprises short duration current pulses
61. An amplifier with negative feedback -
a) lowers its lower 3 dB frequency
b) raises its upper 3 dB frequency
c) increases its bandwidth
d) all of the above
62. What changes would be necessary in block C if FM signals are to be received -
a) Block becomes redundant
b) A FM detector would be required
c) A high frequency signal generator
d) An additional local oscillator will be needed
63. The main disadvantage of Diode-Transistor logic (DTL) is its-
a) greater speed
b) slower speed
c) average speed
d) none of the above
64. Time delay Dt in digital signals in an SIS O shift register is given by –
a) Dt = N ´ Fc
b) Dt = N ´ 1/Fc
c) Dt = 1/N ´ Fc
d) Dt = N ¸ 1/Fc
65. The output Qn is 1 in a JK flip flop and it does not change when clock pulse is applied) The possible combination of Jn and Kn can be –
(y denotes don’t care)
a) y and 0
b) y and 1
c) 0 and y
d) 1 and y
66. Basic memory cell of dynamic RAM consists of –
a) a flip flop
b) a transistor acting as a capacitor
c) a transistor
d) a capacitance
67. The 2’s complement of 10002 is –
a) 0111
b) 0101
c) 1000
d) 0001
68. Master slave flip-flop is made up of –
a) two flip flops connected in series
b) two flip flops connected in parallel
c) a debouncer circuit
d) a-D- latch
69. Number of nybbles making one byte is –
a) 2
b) 4
c) 8
d) 16
70. The intrinsic impedance of free space-
a) is independent of frequency
b) decreases with increase of frequency
c) increases with increase of frequency
d) varies as square root of frequency
71. A system consists of 12 poles and 2 zeroes. Its high frequency asymptote in its magnitude plot has a slope of -
a) –200 dB/decade
b) –240 dB/decade
c) –230 dB/decade
d) –320 dB/decade
72. In a unity feed back control system the open loop transfer function is
The closed loop transfer unit will have pole at –
a) –2, -2
b) –2, -1
c) –2, +j1,-j1
d) –2, 2
73. In a compensating network the transfer function is of the form If this is a phase log network the value of should be –
a) exactly equal to 0
b) between 0 and 1
c) exactly equal to 1
d) greater than 1
74. Considering the conditions-
1. High loop gain 2. Less ringing
3. Greater damping 4 Negative dB gain margin
System stability requirements would include
a) 1 and 3
b) 1, 2 and 3
c) 1 and 4
d) 2, 3 and 4
75. A typical control system is shown.
Assuming the steady state errors is given by
*
76. The centre and radius of M of circles are given respectively by
77. The open –loop transfer function for a unity feedback system is –
what is the steady state error if the input is,
r(t) = (2 + 3t + 4t2) u(t)
a) 0
b) 1
c) 2
d) 3
78. The sensitivity SGM of a system with the transfer function is given by
79. In the equatorial plane only Geosychronous satellite are launched because it is the only plane which provides –
a) 24 hour orbit
b) stationary satellite
c) global communication
d) zero-gravity environs
80. Radio Broadcasting is an example of –
a) space multiplexing
b) time multiplexing
c) frequency multiplexing
d) none of the above
81. PAM signals can be demodulation by using a –
a) Low pass filters (LPE) alone
b) A Schmitt trigger followed by a LPF
c) A differentiator followed by a LPF
d) A clipper circuit by a LPF
82. In an FDM receiver channels can be separated by using –
a) AND gates
b) Band pass
c) differentiation
d) Integration
83. The most common modulation system used for telegraphy is-
a) frequency shift keying
b) two – tone modulation
c) pulse code modulation
d) single tone modulation
84. Use of varoctor diode in generation of modulated segial be-
a) FM generation only
b) 100AM generation only
c) PM generation only
d) both PM and AM generation
85. In colour picture tube shadow mask is used to-
a) reduce x-ray emission
b) ensure that each beam strikes only its own dots
c) increase screen brightness
d) provide degaussing for the screen
86. The circuit that separates composite video warefore from the sync pulses is-
a) the keyed AGC amplifar
b) a clipper
c) an integrator
d) a sawtooth current
87. Band width of microwaves is-
a) 1GHz -103 GHz
b) 1GHz –100 GHz
c) 1 GHz –10 GHz
d) 1 GHz – 106 GHz
88. In transverse Magnetic mode-
a) no electric line is in direction of propagation
b) no magnetic line is in direction of propagation
c) bath magnetic & electric lines are is direction of propagation
d) neither magnetic nor electric lines in direction of propagation
89. Signal transmission in sky wave propagation is due to –
a) Reforction of wave
b) Reflection of wave
c) Pierus through Inosphere
d) None
90. According to Barkhausen Criterion Phase shift of signal should be –
a) 600
b) 900
c) 1800
d) 3600
91. The transmission does not have -
a) Partition noise
b) Flicker noise
c) resistance
d) Short noise
92. Varoctor diode has non linearity of -
a) capacitance
b) Inductance
c) Resistance
d) Is a linear device
93. Scattering matrix equation for directional coupler is –
a)
b)
c)
d)
94. Noise figure is calculated as –
a) i/p signal to noise ratio X o/p signal to noise ratio
b) i/p S/N Ratio / O/P S/N Ratio
c) i/p S/N Ratio / O/P S/N Ratio X 100
d) i/p S/N Ratio + O/P S/N Ratio
95. You can determine quickly the effect of adding poles and zeros by –
a) Nicholas chart
b) Nyquist plot
c) Bode plot
d) Root locus.
96. The polar plot of G(S) = intercepts real axis at w = wo. Then, the real part and wo are given by-
a) –5, 1
b) –2.5, 1
c) –5,0-5
d) –5, 2
97. Laplace transform F (s) of a function f (E) is given by
The initial and final values of F (t) will be respectively-
a) zero and 1
b) zero and 10
c) 10 and zero
d) 70 and 80
98. A satellite link uses different frequencies for receiving and transmitting in order to –
a) avoid interference from terrestrial microwave links
b) avoid interference between its powerful transmitted signals and weak in coming signal
c) minimize free-space losses
d) maximize antenna gain
99. The first determining factor in selecting a satellite system is its-
a) EIRP
b) Antenna size
c) Coverage area
d) Antenna gain
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100. Equalizing pulses in TV are sent during-
a) horizontal blanking
b) vertical blanking
c) the serrations
d) the horizontal retrace
101. The son seems to have ——– from his father a somewhat gloomy and moody manner-
a) washed
b) inherited
c) admired
d) attempt
102. Essayist works with words as sculptor with-
a) water
b) stone
c) air
d) hills
103. What is a collection of sheep called ?
a) bunch
b) flock
c) herd
d) comet
104. Join these sentences meaningfully by choosing the correct alternative from the following :
You can buy a book. You can read it.
a) and
b) nor
c) either
d) neither
105. What is the opposite of Asperity –
a) gentility
b) superiority
c) kindness
d) clarity
106. The Election Commission functions under-
a) Ministry of Home Affairs
b) Ministry of Law
c) Prime Minister’s Secretariat
d) None of these
107. Article 352 of Indian Constitution needs to be revoked in case-
a) President’s Rule is to be imposed
b) Emergency is declared
c) Services of a Government servant are to be terminated without any enquiry
d) A political party of national level is to be banned
108. Radio-activity was first discovered by-
a) Becquerel
b) Madam Curie
c) Rutherford
d) Jenner
109. Ninth Plan in India ranges from-
a) 1995-2000
b) 1996-2001
c) 1997-2002
d) 1998-2003
110. How much electricity does India propose to generate through nuclear power by the year 2000 AD?
a) 5,000 MW
b) 10,000 MW
c) 15,000 MW
d) 20,000 MW
111. In which year did the fall of Bastille take place?
a) 1769
b) 1789
c) 1889
d) 1869
112. To form a quorum how many members of the Lok Sabha or Rajya Sabha should be present?
a) 1/10th of total membership
b) 1/6th of total membership
c) 1/4th of total membership
d) 1/5th of total membership
113. How may countries are non-permanent members of the Security Council?
a) 6
b) 7
c) 9
d) 10
114. The International Date Line is represented by-
a) 1000 meridian
b) 00 meridian
c) 1800 meridian
d) 900 meridian
115. India’s first satellite was launched from-
a) Sriharikota
b) Cape Kennedy
c) Bangalore
d) A Soviet cosmodrome
116. Name the author of the famous book “Politics”-
a) Aristotle
b) Socrates
c) Plato
d) None of them
117. “Guernica” is Picasso’s painting on-
a) The Spanish Civil War
b) The American Civil War
c) The French Revolution
d) The Russian Revolution
118. The object of the Supreme Court’s Keshvanand Bharati ruling is -
a) To put a limit on Parliament’s amendatory powers
b) To give unlimited powers to Parliament to amend the Constitution
c) To give precedence to Directive Principles over Fundamental Rights
d) None of these
119. Which country in July ‘99 officially announced mastering of indigenously developed neutron bomb technology?
a) N. Korea
b) France
c) India
d) China
120. Shifting cultivation is commonly used in which of the following states?
a) Tamil Nadu
b) Maharashtra
c) Jammu and Kashmir
d) Nagaland
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1. Reactive current through the capacitive load produces -
a) Magnetic field
b) Electric field
c) Supermagnetic field
d) None
2. One of the following which gives piero-electric effect is -
a) Mu metal
b) PVDF
c) Sapphire
d) Ferrites
3. PZT piezo- electric materials have -
a) Higher curie temperature
b) Lower curie temperature
c) Absolute temperature
d) None
4. The residual resistivity of a binary alloy at OK is -
a) The sum of the residual resistivities of the component metals
b) The difference of the residual resistivities of the component metals.
c) The product of the residual resistivities of the component metals
d) Dependent on the concentration of the minor component in the alloy
5. In active filter circuits, inductances are avoided mainly because they -
a) Are always associated with some resistance
b) Are bulky and unsuitable for miniaturisation
c) Are non-linear in nature
d) Saturate quickly
6. The depletion layer across a p-n junction lies -
a) mostly in the p-region
b) mostly in the n-region
c) equally to both p and n region
d) entirely in the p-region
7. The voltage induced in a loop of wire rotating in a strong and steady magnetic field is -
a) pulsating dc
b) dc
c) rectified ac
d) ac
8. One of the following types of capacitor which is polarized is -
a) Electrolytic
b) Ceramic
c) Paper
d) Mylar
9. Electric shock is-
a) Always fatal
b) Never fatal
c) Sometimes fatal
d) Always disfiguring
10. A typical value of filter capacitor for 50 Hz ripple is -
a) 16mF
b) 10F
c) 10mF
d) None
11. A telephone relay armature is made of material with -
a) High electrical conductivity
b) Low electrical conductivity
c) Negligible conductivity
d) None
12. Larger the value of filter capacitor -
a) Larger is the peak-peak value of ripple voltage
b) Larger is the peak current in the rectifying diode
c) Longer is the time that current pulse flows through the diode
d) Smaller is the dc voltage across the load
13. Barrier potential in a P-N junction is caused by -
a) Thermally generated electrons and holes
b) Diffusion of majority carriers across the junction
c) Migration of minority carriers across the junction
d) Flow of drift current
14. The polarity of VGS for E-only MOSFET is -
a) positive
b) negative
c) zero
d) depends on P or N channel
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15. The following which will serve as a donor impurity in silicon -
a) Boron
b) Indium
c) Germanium
d) Antimony
16. When bias applied to a vari-cap diode is increased, its capacitance -
a) is decreased
b) is increased
c) remains constant
d) first increases and then decreases.
17. In case of a bipolar transistor a is -
a) positive and greater than 1
b) positive and less than 1
c) negative and greater than 1
d) negative and less than 1
18. A BJT is -
a) not very sensitive to radiations
b) very sensitive to radiations.
c) independent of radiations
d) none
19. An SCR may be considered to be -
a) 2 diodes
b) 3 diodes
c) 4 diodes
d) 5 diodes
20. For a BJT, under the saturation condition -
a) IC = bIB
b) IC > bIB
c) IC is independent of all other parameters
d) IC < bIB
21. In modern MOSFET’s the material used for the gate is -
a) High purity silicon
b) High purity silica
c) Heavily doped polycrystalline silicon
d) Epitaxial grown silicon
22. Find the Norton’s equivalent of the circuit given below -
23. When the source in the circuit shown is a sinusoidal source then the input voltage is -
a) 10V
b) 5V
c) 27V
d) 24V
24. The time constant of the network shown in the given figure is given by -
25. The voltage transfer ratio of two-port networks connected in cascade may be conveniently obtained from the -
a) product of the individual ABCD matrices of the two networks
b) product of voltage transfer ratios of the two individual networks
c) sum of the Z- matrices of the two networks
d) sum of the h – matrices of the two networks
26. When a network has response with time as shown in fig. then which one of the following diagrams represents the location
of the poles of this network ?
27. For the network shown in the given fig. the ratio is -
28. An attenuator drops a 10V signal to 50mv in an experiment. The loss in decibels is -
a) –40dB
b) –6dB
c) –55dB
d) –60dB
29. When the network has 10 nodes and 17 branches then the number of different node pair voltages would be -
a) 7
b) 9
c) 10
d) 45
30. The circuit shown in the following fig. will act as an ideal current source with respect to terminals A and B when
frequency is -
a) zero
b) 1rad/s
c) 4rad/s
d) 16rad/s
31.When a short vertical grounded antenna is required to radiate at 1MHz and the effective height of the antenna is 30 m then
the calculated value of the radiation resistance is -
a) 1.58 W
b) 158 W
c) 15.8 W
d) None of these
32. Shannon’s law relates -
a) antenna gain to bandwidth
b) frequency to antenna gain
c) antenna gain to transmission losses
d) information carrying capacity to S/N ratio
33. One of the following modes which has the characteristic of attenceation becoming less as the frequency is increased and
is attractive at microwave frequencies of circular cylindrical wave guides is -
a) TE1 mode
b) TM01 mode
c) TE01 mode
d) Higher order mode
34.For a transmission line, the propogation constant, for a TEM wave travelling in it is given by (Where the symbols have the
usual meanings ) -
a) [ (R+jwL) (G+jwc)]
b) [ R+jwL) (G+jwc)] ½
c) [ (R-jwL) (G + jwc) ] ½
d) [(R-jwL) ( G+jw2c)]1/3
35. The advantages of wave guides over co-axial lines would include which of the following features-
1. Easier to use 2. lower power losses
3. Higher operating frequencies possible
a) 1 and 2
b) 1 and 3
c) 2 and 3
d) 1,2 and 3
36. When a 75 ohm transmission line is to be terminated in two resistive loads R1 and R2 such that the standing pattern in
the two cases have the same SWR , then the values of R1 and R2 (in ohms) should be -
a) 250 and 200 respectively
b) 225 and 25 respectively
c) 100 and 150 respectively
d) 50 and 125 respectively
37. The degenerate modes in a wave guide are characterized by -
a) Same cut off frequencies but different field distribution
b) Same cut off frequencies and same field distributions
c) Different cut off frequencies but same field distributions
d) Different cut off frequencies and different field distributions
38.A TEM wave impinges obliquely on a dielectric-dielectric boundary with Er1=2 and Er2=1, the angle of incidence for total
reflection is -
a) 30 0
b) 60 0
c) 45 0
d) 90 0
39. The radiation pattern of Hertzian dipole in the plane perpendicular to the dipole is a -
a) Null
b) Circle
c) Figure of eight
d) None of the above
BSNL JTO Recruitment Placement Question Paper free donwload previous years 2007 2008
40. Permeance is the -
a) square of reluctance
b) reluctance
c) reciprocal of the reluctance
d) cube of the reluctance.
41. One of the following which is an active transducer is -
a) Photoelectric
b) Photovoltaic
c) Photo-conductive
d) Photo emission
42. The wein bridge uses only -
a) Inductors
b) Capacitors
c) Resistors
d) Capacitors and Resistors.
43. The greater the value of Q -
a) higher will be the bandwidth of the resonant circuit.
b) smaller will be the bandwidth of the resonant circuit.
c) nothing can be said)
d) none.
44. The most serious source of error in a) c) bridge measurement is -
a) eddy currents
b) leakage currents
c) residual imperfectness
d) stray fields.
45. Moving iron instruments -
a) have a linear scale
b) do not have a linear scale
c) both a and b)
d) none.
46. If accuracy is the main consideration, which one of the following voltmeters should one select -
a) 100 v ; 2 mA
b) 100 v ; 100 ohm/volt
c) 100 v ; 1mA
d) 10,000 v ; 10 mA
47. In dc tacho generators used for measurement of speed of a shaft, frequent calibration has to be done because -
a) the contacts wear off
b) the strength of permanent magnet decreases with age
c) the armature current produces heating effect
d) there is back emf.
48. Ideal transformer cannot be described by -
a) h parameters
b) ABCD parameters
c) G parameters
d) parameters
49. Consider the following statements -
A3- phase balanced supply system is connected to a 3 phase unbalanced load) Power supplied to this load can be measured using
1. Two wattmeters
2. One wattmeter
3. Three wattmeters
Which of these statements is/are correct?
a) 1 and 2
b) 1 and 3
c) 2 and 3
d) 3 alone
50. The function of the reference electrode in a pH meter is to -
a) Produce a constant voltage
b) Provide temperature compensation
c) Provide a constant current
d) Measure average pH value
51. Match the column A (Devices) with column B (Characteristics) and select the correct answer by using the codes given below
the column -
Column A Column B
A) BJT 1. Voltage controlled negative resistance
B) MOSFET 2. High current gain
C) Tunnel diode 3. Voltage regulation
D) Zener diode 4. High input impedance
Codes :
A B C D
a) 1 4 2 3
b) 2 4 1 3
c) 2 3 1 4
d) 1 3 2 4
52. A thyristor during forward blocking state is associated with.-
a) large current , low voltage.
b) low current , large voltage.
c) medium current , large voltage
d) low current, medium voltage.
53. In controlled rectifiers, the nature of load current i.e. whether load current is continuous or discontinuous -
a) does not depend on type of load and firing angle delay
b) depends both on the type of load and firing angle delay
c) depends only on the type of load)
d) depends only on the firing angle delay.
54. A single phase voltage controller feeds power to a resistance of 10 W . The source voltage is 200 V rms. For a firing
angle of 900 , the rms value of thyristor current in amperes is -
a) 20
b) 15
c) 10
d) 5
55. In the performance of single phase and three phase full converters the effect of source inductance is to
a) reduce the ripples in the load current -
b) make discontinuous current as continuous
c) reduce the output voltage
d) increase the load voltage.
56. The cycloconverters (CCs) require natural or forced commutation as under -
a) natural commutation in both step up and step down CCs
b) forced commutation in both step up and step down CCs
c) forced commutation in step up CCs
d) forced commutation in step down CCs
57. Power transistors are more commonly of -
a) silicon npn type.
b) silicon pnp type.
c) silicon nnp type.
d) silicon npp type.
58. C is a -
a)Middle level language
b) High level language
c) Low level language
d) None of above
59. What will be output of program
main ( )
{ int i ;
print f (”Enter value of i”);
scant (”%d”, & i);
if ( i = 5 )
print f (”you entered 5″);
else
print f (”you entered %d”, i ); }
if user entered 100 then
a) 5
b) 100
c) 1005
d) None
60. (7F)16 + (BA)16 = (?)16-
a) 481
b) 139
c) –481
d) –139
61. Two’s complement of 3 bit nonzero linory number is some or original number is all bits accepts-
a) MSB are zeros
b) LSB are zeros
c) MSB are ones
d) LSB are ones.
62. The schematic circuits of RTL NOR gate is-
63. Transistors with high frequency have -
a) Thick base
b) Thin base
c) Some other feature
d) None of the above
64. Telephone traffic is specified in terms of -
a) Average waiting time
b) Grade of service
c) Peak waiting time
d) Erlangs
65. In a Hartley oscillator -
a) Necessary phase relation is obtained by connecting grid and plate electrodes to the opposite ends of the tuned circuit.
b) The mutual inductance must have the appropriate polarity.
c) Both grid circuit and plate tuned circuit offer inductive reactance
d) None of the above
66.The condenser C is charged in a bootstrap sweep generator -
a) Linearly but the discharge is non linear
b) Non linearly but the discharge is linear
c) Linearly and the discharge is linear
d) Non linearly and the discharge is non linear
67.In an audio amplifier audio signals become garbled and hence difficult to understand when an ac input current is large
enough to drive the output to -
a) saturation only
b) Cut off only
c) Either saturation or cut off
d) A value off the load line
68. Five 1 bit registers are referred as -
a) Flags
b) Slags
c) Tags
d) None of the above
69. Next binary number after 0,1, 10, 11 is -
a) 12
b) 101
c) 100
d) 110
70. Identify coincidence logic circuit in the following –
a) b)
c) d)
71. The output analog voltage Vo is given by -
72. If an inverter is placed at the input to an SR flip flop, the result is -
a) T flip flop
b) D flip flop
c) JK flip flop
d) BCD decade counter
73. See the Root locus diagram of a system and the following statements :-
1. The open loop system is a second order system.
2. The system is over damped for
3. The system is absolutely stable for all value of R.
Which of these statements are correct?
a) 1, 2, & 3
b) 1 and 3
c) 2 and 3
d) 1 and 2
74. For the transfer function G(S)H(S) = the phase cross over frequency is -
a) 0.5 rad/sec
b) 0.707 rad/sec
c) 1.732 rad/sec
d) 2 rad/sec
BSNL GE JTO Recruitment Examination previous years 2007 2008 Question Paper free donwload online. solutions coming soon!
75. If the open loop transfer function of the system is G(S) H(S) =
then a closed loop pole will be located at S = -12 wher the value of K is -
a) 4355
b) 5760
c) 9600
d) 9862
76. Considering the following open loop transfer function -
The correct sequence of these systems in increasing order of the time taken for the unit step response to settle is –
a) 1, 2, 3
b) 3, 1, 2
c) 2, 3, 1
d) 3, 2, 1.
77. Considering unit feed back control system in the given figure, the ratio of time constant of closed loop response to open
loop response will be -
a) 1: 1
b) 2 :1
c) 3 : 2
d) 2 : 3
78. Angle subtended by earth at geostationary communication satellite is -
a) 17.340
b) 51.40
c) 1200
d) 600
79.For data transmission phase modulation is commonly used because -
a) Phase can be varied from +1800 to -1800
b) It is resistant to the effects of noise.
c) Demodulation is very easy
d) It gives highest data rates that can be transmitted over a given channel.
80 . Several channels are interleaved and then transmitted together is known as –
a) Frequency division multiplex
b) Time division multiplex
c) A group
d) A super group
81. Identify the wrong statement-
The radar cross section of a target -
a) Depends on the frequency used
b) May be reduced by special coating of the target
c) Depends on the aspect of a target, if this is non spherical
d) Is equal to the actual cross-sectional area for small targets.
82. Considering following parameters -
1. Loss in the media) 2. Permeability of the media) 3. Frequency of the wave 4. Velocity of the wave. Which of these
parameters are responsible for the change of phase of a propagating electromagnetic wave?
a) 1, 2, and 3
b) 2, 3 and 4
c) 1, 3 and 4
d) 1 and 4
83. In super heterodyne receivers double spotting is caused by -
a) poor front-end rejection
b) misalignment of receiver
c) detuning of one or more IF stages.
d) non functioning of AGC
84. The number of lines per field in the United States TV system is -
a) 262 1/2
b) 525
c) 30
d) 60
85. In a TV receiver the color killer -
a) cuts off the chroma stages during monochrome receivers.
b) ensures that no color is transmitted to monochrome receivers
c) prevents color overloading
d) makes sure that the color burst is not mistaken for sync pulses, by cutting off reception during the back porch.
86. The nominal capacitance of a coaxial RF cable is of 40 pF/m and the characteristic impedance of 50W. The inductance of
the cable is-
a) 1mH/m
b) 10 mH/m
c) 0.1 mH/m
d) 0.01 mH/m
87. Transmission of wave through Dominant mode is -
a) distortion less transmission
b) generates undesirable harmonic distortion
c) having loss of power
d) None of above.
88. Lower the standing wave ratio (SWR) -
a) Greater mismatch error
b) Lower mismatch error
c) No effect on matching
d) Moderate mismatch error
89. In klyrtron oscillator for getting wide range of oscillations resonators should be -
a) Critically coupled
b) Under coupled
c) Over coupled
d) No coupling required
90. The critical frequency is always -
a) Lower than maximum usable frequency
b) Equal to maximum usable frequency
c) Higher than maximum usable frequency
d) None of above
91. The PIN diode based on -
a) Nonlinear resistance
b) Nonlinear reactance
c) Negative resistance
d) Controllable impedence
92. Which antenna having circular polarization -
a) Horn antenna
b) Lens antenna
c) Helical antenna
d) Discone antenna
93. The i/p S/N ratio of system is 50 and the o/p S/N ratio is 5 the noise figure is -
a) 250
b) 55
c) 10
d) 45
94. In the 8085 mP, the RST 6 instruction transfers the program execution to the following location -
a) 30 H
b) 24 H
c) 48 H
d) 60 H
95. In instruction cycle first operation is -
a) Memory read
b) Address read
c) Opcode fetch
d) Data read
96. CMP instruction comes under group -
a) Data transfer
b) Branching operations
c) Machine control operation
d) Logical operations.
97.In which logic operation does not effect any flags -
a) ANA B
b) ORA B
c) XRI A2H
d) CMA
98.What happen when CALL instruction executed -
a) Data retrieved from stock to register
b) Data from register saved on the stock.
c) 16 bit address of instruction saved on stock
d) 16 bit address from stock retrieved)
99 The mark status of mark able interrupts is defined according to content of -
a) stack pointer.
b) HL register .
c) Program counter
d) Accumulator
BSNL GE JTO Recruitment Examination Question Paper previous years 2006 2007 2008 free download online. Solutions Coming Soon!
100.The decoder is a logic ckt that -
a) Amplifies the current or power at i/p.
b) Identifies each combination of the signals present at i/p
c) Provides appropriate code as o/p for each i/p signal
d) Both b & c)
101. The young man was quickly promoted when his employers how ————— he was -
a) indigent
b) indifferent
c) assiduous
d) cursory.
102. As letter is alphabet so zodiac is -
a) almanac
b) beacon
c) sign
d) signal.
103.What is the correct meaning of prudish.?
a) careful
b) fast
c) God
d) brave
104. Pick out the odd matching with reference to number -
a) woman – women.
b) hair – hairs
c) child – children.
d) foot – feet.
105.Choose the phrase that is most nearly similiar in meaning to the word given below-
Abut is
a) Stimulate
b) Grasp
c) Oppose
d) Adjoin
106. The highest mountain peak in Indian Territory is -
a) Mount Everest
b) Kanchenjunga
c) Nanda Devi
d) Mount Kailash
107. German silver is an alloy comprising -
a) Copper, Nickel and Zinc
b) Silver, copper and Zinc
c) Silver Nickel and Zinc
d) Nickel, Zinc and Lead
108. Mughal Emperor Bahadur Shah Zafar’s mausoleum is in -
a) Delhi
b) Lahore
c) Yangon
d) Agra
109. On which date the World Trade Centre in New York and Pentagon in Washington d)C was attacked by terrorist -
a) 12 September 2001
b) 11 September 2001
c) 11 July 2001
d) 20 December 2001
110. India defeats South Africa in the finals of the inaugural champions challenge Hockey Tournament in Kualalumpur by -
a) 4-2
b) 2-0
c) 3-2
d) 2-1
111.Which planets in the solar system are known as ‘Inferior Planets’ -
a) Earth and Mars
b) Earth and Mercury
c) Mars and Mercury
d) Mercury and Venus.
112. The largest Stupa in Southern India is at -
a) Nellore
b) Amravati
c) Tanjore
d) Kozhikode
113. The new chairman and Managing Director of Industrial Finance Corporaton of India (IFCI) is -
a) Mr. Vishwanath Prasad Singh
b) Mr. Jitendra Patil
c) Mr. Ragh
d) Mr. Shubhash chand Jain
114. Which one is the latest among rock-cut temples?
a) Ajanta
b) Ellora
c) Elephanta
d) All originated in the same period)
115. Number of organisations government ban in Jammu and Kashmir and the North East under the new ordinance ‘POTO’ is -
a) 20
b) 21
c) 22
d) 23
116. In bed of which river does Badrinath shrine stand?
a) Ganga
b) Mandakini
c) Alakananda
d) Bhagirathi
117. The nerve endings for the sense of sight are located in the part of the eye called the -
a) Cornea
b) Sclera
c) Iris
d) Retina
118. Fundamental duties were introduced in the constitution by the -
a) 40th Amendment
b) 42nd Amendment
c) 43rd Amendment
d) 44th Amendment
119. The Khalsa Panth was founded by -
a) Guru Hargovind
b) Guru Nanak Dev
c) Guru Tegh Bahadur
d) Guru Govind singh
120. Number of countries involved in international fleet review hosted by India is -
a) 27
b) 28
c) 29
d) 30
a) Magnetic field
b) Electric field
c) Supermagnetic field
d) None
2. One of the following which gives piero-electric effect is -
a) Mu metal
b) PVDF
c) Sapphire
d) Ferrites
3. PZT piezo- electric materials have -
a) Higher curie temperature
b) Lower curie temperature
c) Absolute temperature
d) None
4. The residual resistivity of a binary alloy at OK is -
a) The sum of the residual resistivities of the component metals
b) The difference of the residual resistivities of the component metals.
c) The product of the residual resistivities of the component metals
d) Dependent on the concentration of the minor component in the alloy
5. In active filter circuits, inductances are avoided mainly because they -
a) Are always associated with some resistance
b) Are bulky and unsuitable for miniaturisation
c) Are non-linear in nature
d) Saturate quickly
6. The depletion layer across a p-n junction lies -
a) mostly in the p-region
b) mostly in the n-region
c) equally to both p and n region
d) entirely in the p-region
7. The voltage induced in a loop of wire rotating in a strong and steady magnetic field is -
a) pulsating dc
b) dc
c) rectified ac
d) ac
8. One of the following types of capacitor which is polarized is -
a) Electrolytic
b) Ceramic
c) Paper
d) Mylar
9. Electric shock is-
a) Always fatal
b) Never fatal
c) Sometimes fatal
d) Always disfiguring
10. A typical value of filter capacitor for 50 Hz ripple is -
a) 16mF
b) 10F
c) 10mF
d) None
11. A telephone relay armature is made of material with -
a) High electrical conductivity
b) Low electrical conductivity
c) Negligible conductivity
d) None
12. Larger the value of filter capacitor -
a) Larger is the peak-peak value of ripple voltage
b) Larger is the peak current in the rectifying diode
c) Longer is the time that current pulse flows through the diode
d) Smaller is the dc voltage across the load
13. Barrier potential in a P-N junction is caused by -
a) Thermally generated electrons and holes
b) Diffusion of majority carriers across the junction
c) Migration of minority carriers across the junction
d) Flow of drift current
14. The polarity of VGS for E-only MOSFET is -
a) positive
b) negative
c) zero
d) depends on P or N channel
BSNL JTO Recruitment Question Paper previous years 2007 2008
15. The following which will serve as a donor impurity in silicon -
a) Boron
b) Indium
c) Germanium
d) Antimony
16. When bias applied to a vari-cap diode is increased, its capacitance -
a) is decreased
b) is increased
c) remains constant
d) first increases and then decreases.
17. In case of a bipolar transistor a is -
a) positive and greater than 1
b) positive and less than 1
c) negative and greater than 1
d) negative and less than 1
18. A BJT is -
a) not very sensitive to radiations
b) very sensitive to radiations.
c) independent of radiations
d) none
19. An SCR may be considered to be -
a) 2 diodes
b) 3 diodes
c) 4 diodes
d) 5 diodes
20. For a BJT, under the saturation condition -
a) IC = bIB
b) IC > bIB
c) IC is independent of all other parameters
d) IC < bIB
21. In modern MOSFET’s the material used for the gate is -
a) High purity silicon
b) High purity silica
c) Heavily doped polycrystalline silicon
d) Epitaxial grown silicon
22. Find the Norton’s equivalent of the circuit given below -
23. When the source in the circuit shown is a sinusoidal source then the input voltage is -
a) 10V
b) 5V
c) 27V
d) 24V
24. The time constant of the network shown in the given figure is given by -
25. The voltage transfer ratio of two-port networks connected in cascade may be conveniently obtained from the -
a) product of the individual ABCD matrices of the two networks
b) product of voltage transfer ratios of the two individual networks
c) sum of the Z- matrices of the two networks
d) sum of the h – matrices of the two networks
26. When a network has response with time as shown in fig. then which one of the following diagrams represents the location
of the poles of this network ?
27. For the network shown in the given fig. the ratio is -
28. An attenuator drops a 10V signal to 50mv in an experiment. The loss in decibels is -
a) –40dB
b) –6dB
c) –55dB
d) –60dB
29. When the network has 10 nodes and 17 branches then the number of different node pair voltages would be -
a) 7
b) 9
c) 10
d) 45
30. The circuit shown in the following fig. will act as an ideal current source with respect to terminals A and B when
frequency is -
a) zero
b) 1rad/s
c) 4rad/s
d) 16rad/s
31.When a short vertical grounded antenna is required to radiate at 1MHz and the effective height of the antenna is 30 m then
the calculated value of the radiation resistance is -
a) 1.58 W
b) 158 W
c) 15.8 W
d) None of these
32. Shannon’s law relates -
a) antenna gain to bandwidth
b) frequency to antenna gain
c) antenna gain to transmission losses
d) information carrying capacity to S/N ratio
33. One of the following modes which has the characteristic of attenceation becoming less as the frequency is increased and
is attractive at microwave frequencies of circular cylindrical wave guides is -
a) TE1 mode
b) TM01 mode
c) TE01 mode
d) Higher order mode
34.For a transmission line, the propogation constant, for a TEM wave travelling in it is given by (Where the symbols have the
usual meanings ) -
a) [ (R+jwL) (G+jwc)]
b) [ R+jwL) (G+jwc)] ½
c) [ (R-jwL) (G + jwc) ] ½
d) [(R-jwL) ( G+jw2c)]1/3
35. The advantages of wave guides over co-axial lines would include which of the following features-
1. Easier to use 2. lower power losses
3. Higher operating frequencies possible
a) 1 and 2
b) 1 and 3
c) 2 and 3
d) 1,2 and 3
36. When a 75 ohm transmission line is to be terminated in two resistive loads R1 and R2 such that the standing pattern in
the two cases have the same SWR , then the values of R1 and R2 (in ohms) should be -
a) 250 and 200 respectively
b) 225 and 25 respectively
c) 100 and 150 respectively
d) 50 and 125 respectively
37. The degenerate modes in a wave guide are characterized by -
a) Same cut off frequencies but different field distribution
b) Same cut off frequencies and same field distributions
c) Different cut off frequencies but same field distributions
d) Different cut off frequencies and different field distributions
38.A TEM wave impinges obliquely on a dielectric-dielectric boundary with Er1=2 and Er2=1, the angle of incidence for total
reflection is -
a) 30 0
b) 60 0
c) 45 0
d) 90 0
39. The radiation pattern of Hertzian dipole in the plane perpendicular to the dipole is a -
a) Null
b) Circle
c) Figure of eight
d) None of the above
BSNL JTO Recruitment Placement Question Paper free donwload previous years 2007 2008
40. Permeance is the -
a) square of reluctance
b) reluctance
c) reciprocal of the reluctance
d) cube of the reluctance.
41. One of the following which is an active transducer is -
a) Photoelectric
b) Photovoltaic
c) Photo-conductive
d) Photo emission
42. The wein bridge uses only -
a) Inductors
b) Capacitors
c) Resistors
d) Capacitors and Resistors.
43. The greater the value of Q -
a) higher will be the bandwidth of the resonant circuit.
b) smaller will be the bandwidth of the resonant circuit.
c) nothing can be said)
d) none.
44. The most serious source of error in a) c) bridge measurement is -
a) eddy currents
b) leakage currents
c) residual imperfectness
d) stray fields.
45. Moving iron instruments -
a) have a linear scale
b) do not have a linear scale
c) both a and b)
d) none.
46. If accuracy is the main consideration, which one of the following voltmeters should one select -
a) 100 v ; 2 mA
b) 100 v ; 100 ohm/volt
c) 100 v ; 1mA
d) 10,000 v ; 10 mA
47. In dc tacho generators used for measurement of speed of a shaft, frequent calibration has to be done because -
a) the contacts wear off
b) the strength of permanent magnet decreases with age
c) the armature current produces heating effect
d) there is back emf.
48. Ideal transformer cannot be described by -
a) h parameters
b) ABCD parameters
c) G parameters
d) parameters
49. Consider the following statements -
A3- phase balanced supply system is connected to a 3 phase unbalanced load) Power supplied to this load can be measured using
1. Two wattmeters
2. One wattmeter
3. Three wattmeters
Which of these statements is/are correct?
a) 1 and 2
b) 1 and 3
c) 2 and 3
d) 3 alone
50. The function of the reference electrode in a pH meter is to -
a) Produce a constant voltage
b) Provide temperature compensation
c) Provide a constant current
d) Measure average pH value
51. Match the column A (Devices) with column B (Characteristics) and select the correct answer by using the codes given below
the column -
Column A Column B
A) BJT 1. Voltage controlled negative resistance
B) MOSFET 2. High current gain
C) Tunnel diode 3. Voltage regulation
D) Zener diode 4. High input impedance
Codes :
A B C D
a) 1 4 2 3
b) 2 4 1 3
c) 2 3 1 4
d) 1 3 2 4
52. A thyristor during forward blocking state is associated with.-
a) large current , low voltage.
b) low current , large voltage.
c) medium current , large voltage
d) low current, medium voltage.
53. In controlled rectifiers, the nature of load current i.e. whether load current is continuous or discontinuous -
a) does not depend on type of load and firing angle delay
b) depends both on the type of load and firing angle delay
c) depends only on the type of load)
d) depends only on the firing angle delay.
54. A single phase voltage controller feeds power to a resistance of 10 W . The source voltage is 200 V rms. For a firing
angle of 900 , the rms value of thyristor current in amperes is -
a) 20
b) 15
c) 10
d) 5
55. In the performance of single phase and three phase full converters the effect of source inductance is to
a) reduce the ripples in the load current -
b) make discontinuous current as continuous
c) reduce the output voltage
d) increase the load voltage.
56. The cycloconverters (CCs) require natural or forced commutation as under -
a) natural commutation in both step up and step down CCs
b) forced commutation in both step up and step down CCs
c) forced commutation in step up CCs
d) forced commutation in step down CCs
57. Power transistors are more commonly of -
a) silicon npn type.
b) silicon pnp type.
c) silicon nnp type.
d) silicon npp type.
58. C is a -
a)Middle level language
b) High level language
c) Low level language
d) None of above
59. What will be output of program
main ( )
{ int i ;
print f (”Enter value of i”);
scant (”%d”, & i);
if ( i = 5 )
print f (”you entered 5″);
else
print f (”you entered %d”, i ); }
if user entered 100 then
a) 5
b) 100
c) 1005
d) None
60. (7F)16 + (BA)16 = (?)16-
a) 481
b) 139
c) –481
d) –139
61. Two’s complement of 3 bit nonzero linory number is some or original number is all bits accepts-
a) MSB are zeros
b) LSB are zeros
c) MSB are ones
d) LSB are ones.
62. The schematic circuits of RTL NOR gate is-
63. Transistors with high frequency have -
a) Thick base
b) Thin base
c) Some other feature
d) None of the above
64. Telephone traffic is specified in terms of -
a) Average waiting time
b) Grade of service
c) Peak waiting time
d) Erlangs
65. In a Hartley oscillator -
a) Necessary phase relation is obtained by connecting grid and plate electrodes to the opposite ends of the tuned circuit.
b) The mutual inductance must have the appropriate polarity.
c) Both grid circuit and plate tuned circuit offer inductive reactance
d) None of the above
66.The condenser C is charged in a bootstrap sweep generator -
a) Linearly but the discharge is non linear
b) Non linearly but the discharge is linear
c) Linearly and the discharge is linear
d) Non linearly and the discharge is non linear
67.In an audio amplifier audio signals become garbled and hence difficult to understand when an ac input current is large
enough to drive the output to -
a) saturation only
b) Cut off only
c) Either saturation or cut off
d) A value off the load line
68. Five 1 bit registers are referred as -
a) Flags
b) Slags
c) Tags
d) None of the above
69. Next binary number after 0,1, 10, 11 is -
a) 12
b) 101
c) 100
d) 110
70. Identify coincidence logic circuit in the following –
a) b)
c) d)
71. The output analog voltage Vo is given by -
72. If an inverter is placed at the input to an SR flip flop, the result is -
a) T flip flop
b) D flip flop
c) JK flip flop
d) BCD decade counter
73. See the Root locus diagram of a system and the following statements :-
1. The open loop system is a second order system.
2. The system is over damped for
3. The system is absolutely stable for all value of R.
Which of these statements are correct?
a) 1, 2, & 3
b) 1 and 3
c) 2 and 3
d) 1 and 2
74. For the transfer function G(S)H(S) = the phase cross over frequency is -
a) 0.5 rad/sec
b) 0.707 rad/sec
c) 1.732 rad/sec
d) 2 rad/sec
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75. If the open loop transfer function of the system is G(S) H(S) =
then a closed loop pole will be located at S = -12 wher the value of K is -
a) 4355
b) 5760
c) 9600
d) 9862
76. Considering the following open loop transfer function -
The correct sequence of these systems in increasing order of the time taken for the unit step response to settle is –
a) 1, 2, 3
b) 3, 1, 2
c) 2, 3, 1
d) 3, 2, 1.
77. Considering unit feed back control system in the given figure, the ratio of time constant of closed loop response to open
loop response will be -
a) 1: 1
b) 2 :1
c) 3 : 2
d) 2 : 3
78. Angle subtended by earth at geostationary communication satellite is -
a) 17.340
b) 51.40
c) 1200
d) 600
79.For data transmission phase modulation is commonly used because -
a) Phase can be varied from +1800 to -1800
b) It is resistant to the effects of noise.
c) Demodulation is very easy
d) It gives highest data rates that can be transmitted over a given channel.
80 . Several channels are interleaved and then transmitted together is known as –
a) Frequency division multiplex
b) Time division multiplex
c) A group
d) A super group
81. Identify the wrong statement-
The radar cross section of a target -
a) Depends on the frequency used
b) May be reduced by special coating of the target
c) Depends on the aspect of a target, if this is non spherical
d) Is equal to the actual cross-sectional area for small targets.
82. Considering following parameters -
1. Loss in the media) 2. Permeability of the media) 3. Frequency of the wave 4. Velocity of the wave. Which of these
parameters are responsible for the change of phase of a propagating electromagnetic wave?
a) 1, 2, and 3
b) 2, 3 and 4
c) 1, 3 and 4
d) 1 and 4
83. In super heterodyne receivers double spotting is caused by -
a) poor front-end rejection
b) misalignment of receiver
c) detuning of one or more IF stages.
d) non functioning of AGC
84. The number of lines per field in the United States TV system is -
a) 262 1/2
b) 525
c) 30
d) 60
85. In a TV receiver the color killer -
a) cuts off the chroma stages during monochrome receivers.
b) ensures that no color is transmitted to monochrome receivers
c) prevents color overloading
d) makes sure that the color burst is not mistaken for sync pulses, by cutting off reception during the back porch.
86. The nominal capacitance of a coaxial RF cable is of 40 pF/m and the characteristic impedance of 50W. The inductance of
the cable is-
a) 1mH/m
b) 10 mH/m
c) 0.1 mH/m
d) 0.01 mH/m
87. Transmission of wave through Dominant mode is -
a) distortion less transmission
b) generates undesirable harmonic distortion
c) having loss of power
d) None of above.
88. Lower the standing wave ratio (SWR) -
a) Greater mismatch error
b) Lower mismatch error
c) No effect on matching
d) Moderate mismatch error
89. In klyrtron oscillator for getting wide range of oscillations resonators should be -
a) Critically coupled
b) Under coupled
c) Over coupled
d) No coupling required
90. The critical frequency is always -
a) Lower than maximum usable frequency
b) Equal to maximum usable frequency
c) Higher than maximum usable frequency
d) None of above
91. The PIN diode based on -
a) Nonlinear resistance
b) Nonlinear reactance
c) Negative resistance
d) Controllable impedence
92. Which antenna having circular polarization -
a) Horn antenna
b) Lens antenna
c) Helical antenna
d) Discone antenna
93. The i/p S/N ratio of system is 50 and the o/p S/N ratio is 5 the noise figure is -
a) 250
b) 55
c) 10
d) 45
94. In the 8085 mP, the RST 6 instruction transfers the program execution to the following location -
a) 30 H
b) 24 H
c) 48 H
d) 60 H
95. In instruction cycle first operation is -
a) Memory read
b) Address read
c) Opcode fetch
d) Data read
96. CMP instruction comes under group -
a) Data transfer
b) Branching operations
c) Machine control operation
d) Logical operations.
97.In which logic operation does not effect any flags -
a) ANA B
b) ORA B
c) XRI A2H
d) CMA
98.What happen when CALL instruction executed -
a) Data retrieved from stock to register
b) Data from register saved on the stock.
c) 16 bit address of instruction saved on stock
d) 16 bit address from stock retrieved)
99 The mark status of mark able interrupts is defined according to content of -
a) stack pointer.
b) HL register .
c) Program counter
d) Accumulator
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100.The decoder is a logic ckt that -
a) Amplifies the current or power at i/p.
b) Identifies each combination of the signals present at i/p
c) Provides appropriate code as o/p for each i/p signal
d) Both b & c)
101. The young man was quickly promoted when his employers how ————— he was -
a) indigent
b) indifferent
c) assiduous
d) cursory.
102. As letter is alphabet so zodiac is -
a) almanac
b) beacon
c) sign
d) signal.
103.What is the correct meaning of prudish.?
a) careful
b) fast
c) God
d) brave
104. Pick out the odd matching with reference to number -
a) woman – women.
b) hair – hairs
c) child – children.
d) foot – feet.
105.Choose the phrase that is most nearly similiar in meaning to the word given below-
Abut is
a) Stimulate
b) Grasp
c) Oppose
d) Adjoin
106. The highest mountain peak in Indian Territory is -
a) Mount Everest
b) Kanchenjunga
c) Nanda Devi
d) Mount Kailash
107. German silver is an alloy comprising -
a) Copper, Nickel and Zinc
b) Silver, copper and Zinc
c) Silver Nickel and Zinc
d) Nickel, Zinc and Lead
108. Mughal Emperor Bahadur Shah Zafar’s mausoleum is in -
a) Delhi
b) Lahore
c) Yangon
d) Agra
109. On which date the World Trade Centre in New York and Pentagon in Washington d)C was attacked by terrorist -
a) 12 September 2001
b) 11 September 2001
c) 11 July 2001
d) 20 December 2001
110. India defeats South Africa in the finals of the inaugural champions challenge Hockey Tournament in Kualalumpur by -
a) 4-2
b) 2-0
c) 3-2
d) 2-1
111.Which planets in the solar system are known as ‘Inferior Planets’ -
a) Earth and Mars
b) Earth and Mercury
c) Mars and Mercury
d) Mercury and Venus.
112. The largest Stupa in Southern India is at -
a) Nellore
b) Amravati
c) Tanjore
d) Kozhikode
113. The new chairman and Managing Director of Industrial Finance Corporaton of India (IFCI) is -
a) Mr. Vishwanath Prasad Singh
b) Mr. Jitendra Patil
c) Mr. Ragh
d) Mr. Shubhash chand Jain
114. Which one is the latest among rock-cut temples?
a) Ajanta
b) Ellora
c) Elephanta
d) All originated in the same period)
115. Number of organisations government ban in Jammu and Kashmir and the North East under the new ordinance ‘POTO’ is -
a) 20
b) 21
c) 22
d) 23
116. In bed of which river does Badrinath shrine stand?
a) Ganga
b) Mandakini
c) Alakananda
d) Bhagirathi
117. The nerve endings for the sense of sight are located in the part of the eye called the -
a) Cornea
b) Sclera
c) Iris
d) Retina
118. Fundamental duties were introduced in the constitution by the -
a) 40th Amendment
b) 42nd Amendment
c) 43rd Amendment
d) 44th Amendment
119. The Khalsa Panth was founded by -
a) Guru Hargovind
b) Guru Nanak Dev
c) Guru Tegh Bahadur
d) Guru Govind singh
120. Number of countries involved in international fleet review hosted by India is -
a) 27
b) 28
c) 29
d) 30
BSNL JTO
1. When a inductive coil connected to a 200 V, 50Hz ac supply with 10A current flowing through it dissipates 1000 watts then
which of the following will have least value in ohms-
a.) Resistance
b.) Reactance
c.) Impedance
d.) None
2 Oscillator crystal are made of –
a.) Silicon
b.) Germanium
c.) Quartz
d.) None
3. For small size, high frequency coils, the most common core material is-
a. )Air
b. )Ferrite
c.) Powdered ion
d.) Steel
4. If we have a parallel plate capacitor of plate area ‘A’ and plate separatoin t and having a capacity C and a metallic
plate r of area A and of negligible thickness is introduced in the capacitor at a distance from either of the two plates as
shown in the given figure then the capacity of the capacitor will become –
a.)
b.)C
c.)2C
d.)4C
5. A superconductor is a –
a.)A material showing perfect conductivity and Meissner effect below a critical temperature
b.)A conductor having zero resistance
c.)A perfect conductor with highest di-magnetic susceptibility
d.)A perfect conductor which becomes resistance when the current density through it exceeds a critical value
6. When an inductor tunes at 200 KHz with 624 pF capacitor and at 600 KHz with 60.4 pF capacitor then the self capacitance of
the inductor would be –
a)8.05 pF
b)10.05pF
c.)16.01pF
d.)20.01pF
7. Sparking occur when a load is switched off because the circuit has high –
a.)Inductance
b.)Capacitance
c.)Resistance
d.)None
8. Sparking between contacts can be reduced by inserting a –
a.)Resistance in the line
b.)Capacitor in series with contacts
c.)Capacitor in parallel with contacts
d.)None
9. RF amplifier of an A.M. receiver is normally biased in –
a.)Class ‘A’
b.)Class ‘b’
c.)Class ‘C’
d.)None
10. The value of gate voltage for the operation of enhancement of only N channel MOSFET has to be –
a.)High positive
b.)High negative
c.)Low positive
d.)Zero
11. The input gate current of a FET is –
a.)a few microamperes
b.)negligibly small
c.)a few milliamperes
d.)a few amperes
12. In the following fig. with R = 30k, the value of current through 2 K resistor is –
a.)25 mA
b.)40 mA
c.)25/16 mA
d.)10 mA
13. A step recovery diode –
a.)has on extremely short recovery time
b.)conducts equally well in both directions
c.)is mainly used as a harmonic generator
d.)is an ideal rectifiers of high frequency signals
14. In order to get maximum undistorted output signal from CE amplifier with VCC 10V, the value of VCE (Q) should be
approximately-
a.)0.1V
b.)5V
c.)10V
d) V
15. In a FET the electrode, which corresponds to collector in bipolar transistor, is –
a.)source
b.)drain
c.)gate
d.)none
16. The device which acts like an NPN and a PNP transistor connected base to base and emitter to collector is –
a.)Triac
b.)UJT
c.)Diac
d.)SCR
17. A typical optical fibre has –
a.)High refractive index core and low refractive index cladding
b.)Low refractive index core and high refractive index cladding
c.)Both a and b
d.)None
18. In the following figure circuit diagram of an op-amp based is shown. The ratio is equal to –
a.)9
b.)11
c.)10
d.)21
19. When a loud speaker is connected across the terminals A and B of the network shown in the fig. then its impedance to
obtain maximum power dissipation in it will be –
a.)3 – j1
b.)3 + j9
c.)7.5 + j 2.5
d.)7.5 – j 2.5
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20. In the lattice network, the value of R for the maximum power transfer to the load –
a.)5
b.)6.5
c.)8
d.)9
21. For a lossy transmission line short circuited at the receiving end, the input impedance is given by (Z0 is the
characteristic impedance, Ö is the propagation constant and l is the length of the line-
a.)Z0 cot h Öl
b.)Z0 cot Öl
c.)Z0 tan h.Ö l
d.) Z0 tan Öl
22. The approximate thickness of the radome wall should be –
a.)l
b.)l/4
c.)l/2
d.)l/
23 A relatively permanent information is stored in
a. )ROM
b.)RAM
c.)PROM
d.)Volatile memory
24. The rise time of the RC network shown in the given figure is approximately equal to –
b.) RC
c.) 2RC
d.) 4RC
25. If in the network shown in the fig. initially a steady state is attained by closing the switch ’s’ and then if the switch
is opened at t = 0, then the current i(t) through the inductor will be –
a.) cos50tA
b.) 2A
c.) 2cos100tA
d.) 2sin50tA
26. When the p network of figure – I and T-network of figure – II are equivalent then the values of R1, R2 and R3 will be
respectively –
a) 9W, 6W and 6W
b.) 6W, 6W and 9W
c.) 9W, 6W and 9W
d.) 6W, 9W and 6W
27. When the impedance matrices of a two port networks are given by and , then if these two networks are connected in series
then the impedance matrix of the resulting two-port network will be –
d.) indeterminate
28. Joule/coulomb is the unit of -
a.) Electric field potential
b.) Potential
c .) Charge
d.) None of the above
29. The electric field line and equipotential lines-
a.) Are parallel to each other
b.)Are one and same
c.) Cut each other orthogonally
d.)Can be inclined to each other at any angle
30. For a lossy transmission line short circuited at the receiving end, the input impedance is given by (When Z0 is the
characteristic impendence g is the propagation constant and L is the length of the line
31. When two equal positive point charges are placed along X- axis at X1 and –X1 respectively then the electric field vector
at a point P on the positive Y-axis will be directed-
a.) In the +x direction
b.) In the –x direction
c. ) In the +y direction
d.) In the –y direction
32. The directions of and in TEM mode transmission line with respect to the direction of propagation are-
a.) Both and are transverse to the direction of propagation
b.) is and are transverse and h has a component in the direction of propagation
c.) is entirely transverse and has a component in the direction of propagation
d.) is entirely transverse and has a component in the direction of propagation
33. The lowest TM mode in a rectangular waveguide of cross –section a x b with a>b will be-
a.) TM01
b.)TE10
c.) TM112
d.)TE11
34. When a transmitter in a free space radiates a mean power of ‘p’ watts uniformly in all directions then at a distance d
sufficiently far from the source in plane the electric field E should be related to p and d as –
35. When a dipole antenna was radiating with some excitation in free space radiating a certain amount of the power v if then
this antenna is immersed in a lake where water is non-dissipative but has a dielectric constant of 81, then the radiated
power with the same excitation will be
a.) Decrease to finite non-zero value
b.)Remain the same
c. )Increase
d.)Decrease to zero
36. When a (75 – j40)W load is connected to a coaxial line of Z0 = 75 W at 6MHz then the load matching on the line can be
accomplished by connecting-
a.) A short – circuited stub at the load
b.)An inductance at the load
c. )A short circuited stub at a specific distance from the load
d.)none of the above
37. As compared to analog multimeters, digital multimeters are –
a.) less accurate
b.) more accurate
c.) equally accurate
d.) none.
38. When a signal of 10 mV at 75 MHz is to be measured then which of the following instruments can be used –
a.) VTVM
b.) Cathode ray oscilloscope
c.) Moving iron voltmeter
d.) Digital multimeter
39. Which of the following statement is true about two wattmeter method for power measurement in three phase current ?
a.) power can be measured using two wattmeter method only for star connected three phase circuits.
b.) when two meter show indentical readings, in the power factor is 0.5.
c.) when power factor is unit, one of the wattmeter reads zero
d.) when the reading of the two wattmeters are equal but of opposite sign, then the power factor is zero –
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40. When a capacitance transducer has two plates of area 5cm2 each, separated by an air gap of 2mm than the displacement
sensitivity in pf/cm due to gap change would be –
a.) 11.1
b.) 44.2
c.) 52.3
d.) 66.3
41. The Q of a radio coil –
a.) is independent of frequency
b.) increases monotonically as frequency increases
c.) decreases monotonically as frequency increases
d.) increases upto a certain frequency and then decreases beyond that frequency
42. When a generator of internal impedance and operating at 1GHz feeds a load via a coaxial line of characteristic impedance
50 ohm then the voltage wave ratio on the feed line is –
a.) 0.5
b.) 1.5
c.) 2.5
d.) 1.75
43. The coding system typically used in digital telemetry is –
a.) PPM (pulse position modulation)
b.) PAM (pulse amplitude modulation)
c.) PCM (pulse code modulation)
d.) PDM (pulse duration modulation)
44. Radiation pyrometers are used for the measurement of temperature in the range of –
a.) -2000C to 5000C
b.) 00C to 5000C
c.) 5000C to 12000C
d.) 12000C to 25000C
45. In the given figure band structure is shown. It is of –
a.) Gallium Avesenide (GaAs)
b.) Silicon (Si)
c.) Copper (Cu)
d.) Germanium (Ge)
46. When anode is positive with respect to cathode in an SCR, the numbers of blocked p-n junction is –
a.) 1
b.) 2
c.) 3
d.) 4
47. The circuit symbol for a GTO is
a. b.
c. d.
48. In the given fig. mark out the type of Cyclo converters
a.) 1 phase to 1 phase with continuous conduction
b.) 1 phase to 1 phase with discontinuous conduction
c.) step up device
d.) 3 phase to 1 phase device
49. In the given fig. A-1, C=5, m H and C=20 m F, C is initially charged to 200 V. After the switch.
S is closed at t = 0 the
maximum value of current and the
time at which it reaches this value are respectively.
a.) 400 A, 15.707 mS
b.) 50 A, 30 mS
c.) 100 A, 62.828 mS
d.) 400 A, 31.414 mS
50. In the given circuit the maximum current in the main SCR M can be-
a.) 200 A
b.) 170.7 A
c.) 141.4 A
d.) 70.7 A
51. The transfer function of an amplifier is given by
The high 3-db frequency of the amplifier will approximately
a.) 5850 KHZ
b.)585 KHZ
c.) 5850 HZ
d.)585HZ
52. In comparison to full wave rectifier with two diodes the four divide bridge rectifier has the dominant advantage of -
a). Higher current carrying
b.)Lower ripple factor
c.) Higher efficiency
d.)Lower peak increase voltage require
53. Power output increase in a class-c amplifier-
a.) If the conduction angle decrease
b).If the conduction angle increase
c.) Are not governed by the conduction angle
d.)None of the above
54. A transistor with hie = 1.5 k and hfe = 75 is used in an emitter follower circuit where R1 and R2 are used for normal
biasing . Approximate value of it’s current amplification is-
a.)75
b.)76
c.)75/76
d.)-75
55. Amplifier of class B has high theoretical efficiency of 78.5 percent because-
a.) It is biased almost to saturation
b.)Its quiescent current is low
c.)It’s output is an exact replica of it’s input
d.)It is biased well below cut off
56. The coupling that produces minimum interference with frequency response is-
a.) Direct coupling
b.)Impedance coupling
c.) R C coupling
d.)Transformer coupling
57. In the circuit shown in the given figure Rf provides
a.) Current series feedback
b.)Current shunt feedback
c.) Voltage series feedback
d.)Voltage shunt feedback
58. Mark the correct relation for the junction transistor
59. Data in the serial form can be converted into parallel form by using –
a.) PISO shift register
b.) SOIP shift register
c.) SIPO shift register
d.) POIS shift register
60. PROMs are used to store-
a.) bulk information
b.) information to be accessed rarely
c.) sequence information
d.) relatively permanent information
61. The horizontal axis in a 3 bit unipolar D/A converter represents-
a.) Output bit combination
b.) analog output voltage
c.) input bit combination
d.) none of the above
62. ‘Not allowed’ condition in NAND gate SR flip flop is –
a.) s = 0, R = 0
b.) s = 1, R = 1
c.) s = 0, R = 1
d.) s = 1, R = 0
63. Name the fastest logic family-
a) TTL
b. RTL
c.) DCTL
d.) ECL
64. Equation corresponding to De Morgan’s theorem in Boolean Algebra is –
a.) (A+B) (A+B) = AA + AB + BA + BB
c.) A + AB = A
d.) None of the above
65. In the given fig find radix of the system –
a.) 2b.) 4
c.) 6
d.) 8
66. Modems are used for data transmission telephone lines to –
a.) increase the transmission capacity
b) improve noice performance
c.) incorporate error control coding
d.) eliminate dc component in the transmitted signal
67. The figure of a control system is shown. The maximum value of gain K for which the system is stable is-
a.)
b.) 3
c.) 4
d.) 5
68. Identify the example of open-loop system-
a.) A windscreen wiper
b.) Aqualung
c.) Respiratory system of an animal
d.) A system for controlling Anti-rocket missiles.
69. Consider the following expressions indicating the step or impulse response of an initially relaxed control system-
1. (5 – 4e-2+) u(t)
2. (e-2t +5) (u(t))
3 .V(t) + 8e-2t u(t)
4 . V(t) + 4e-2t 4(t)
Those which correspond to the step and impulse response of the same system include-
a.) 1&3
b.) 1&4
c.) 2&4
d.) 1&4
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70. A system is described by
To test its stability by Lyapunov’s method the following V functions are considered.
Mark the most suitable V-function in this case-
a.) Only V1
b.)Only V2
c.) Both V1 and V2
d.) Neither V1 nor v2
71. Identity the polar plot of a typical type zero system with open loop transfer function
72. The scattering matrix of a magic –tee shown in the given figure is-
73. Which is the following relate to rational transfer function of a system-
1. Ratio of Fourier transform of output to input with zero initial conditions.
2. Ratio of Laplace transform of output to input with zero initial conditions.
3. Laplace transform of system impulse response.
4. Laplace transform of system unit step response select the correct answer using the codes given below.
Codes
a.) 1 and 4
b.) 2 and 3
c.) 1 and 3
d.) 2 and 4
74. For the signal g (t) – 10 cos (50 pt) cos2 (150at)
The Nyquist sampling state in t seconds is
a.) 150 samples per second
b.) 200 samples per second
c.) 300 samples per second
d.) 350 samples per second
75. In the case of a 70 MHz 1F carries for a transponder band width of 36 MHz; energy must lie between – MHz.
a.) 34 and 106
b.) 52. And 88
c.) 106 and 142
d.) 34 and 142
76. Radar used to eliminate clutter in navigational application is –
a.) Pulse radar
b.) Tracking radar
c.) MTI radar
d.) Mono pulse radar
77. The 1.55 mm windows is not yet in use with fiber optic systems because –
a.)The attenuation is higher than at 0.85 mm
b) The attenuation is higher than at 1.3mm
c.) Suitable laser devices have not yet been developed
d.) It does not lend itself to wavelength multiplexing
78. Pre-emphasis in FM systems involves-
a.) Compression of the modulating signal
b.) Expansion of the modulating signal
c.) Amplification of lower frequency components of the modulating signal.
d.) Amplification of higher frequency components of the modulating signal.
79. In a terrestrial microwave system transmission of signals is achieved through-
a.) reflection from the ionosphere
b.) line of sight mode
c) reflection from the ground
d.) diffraction from the stratosphere.
80. Casse grain feed is used with a parabolic reflector to
a.) increase the gain of the system
b). increase the bandwidth of the system
c.) reduce the size of the main reflector
d.) allow the feed to be placed at a convenient point.
81. In most microwave communication link rain drop attenuation is caused due to-
a.) scattering of microwaves by water drops of specific size.
b) scattering of microwaves by a collection of droplets acing as a single body.
c.) absorption of microwaves by water and consequent heating of the liquid
d.) absorption of the microwaves by water vapor in the atmosphere.
82. Circuit in the given figure represents. –
a.) an astable multivibrator
b.) A monostable multivibrator
c.) Voltage controlled oscillator
d.) Ramp generator
83. . D = r is-
a.) Maxwell’s 1st equation
b.) Maxwell’s II equation
c.) Maxwell’s III equation
d.) Maxwell’s IV equation
84. In a rectangular wave-guide which TM mode exists-
a.) TM00
b.) TM01
c.) Tm10
d.) TM11
85. In directional coupler a portion of power two velliry fram port 1) to port 2) is coupled to.
a). port 4
b). port 3
c. port 2.
d.) port 3 & 4.
86. For high power i.e. 10 w to 50 kw measurement –
a.) Barometer are used
b.) Thermisters are used
c.) Calorimetric technique
d.) Calorimetric watt meter technique used
87. The difference between TWT & klystron is –
a.) In TWT electrons are in contact with RF field for long time & in klystron for short time
b.) In klystron electrons are in contact with RF field for long time & in TWT for short time
c.) In klystron there is no contact in RF field & electrons while in TWT there is contact
d.) In TWT phase is no contact is RF field & electrons while in klystron there is contact
88. Which one is most suitable for transmission through wave guide-
a.) Hown antennas
b.) Bioconical antennas
c.) helical antenna
d. Discone
89. The skip distance of microwave is given by –
a.)
b.)
c.)
d.)
90. How many general purpose registers 8085mp-
a.) 4
b.) 6
c.) 8
c.) 10
91. 8085 mP has no. of addressing modes-
a.) 2
b.) 3
c.) 4
d.) 5
92. What will be status of z and c y flag after execution of SUB A instruction
a.) z = 0, cy = 0
b.) z = 0, cy = 1
c.) z = 1, cy = 0
d.) z = 1, cy = 1
93. Microprocessor accept interrupt only if.
a.) interrupt flip flop disabled.
b.) when INTA signal is low.
c. interrupt flip flop enabled.
d.) none of above.
94. Microprogramming is a technique
a.) for programming the microprocessor
b.) for writing small programs efficiently
c.) for programming the control steps of computer
d.) for programming o/p / i/p
95. High level programs like C are converted into machine language with the help of
a.) interpreter
b.) compiler
c.) operating
d.) system
96. (10110011)2 = (?)8
a.) 253
b.) 263
c.) 273
d.) 283
97. A Not gate at the output of AND gate converts AND gate into-
a.) NAND
b.) NOR
c.) AND
d.) NOPE.
98. The O/P of a logic gate is the gate must be-
a.) AND
b.) OR
c.) NAND
d.) X-OR
99. 38. A symbol of JK flip flop is-
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100. A demultiplener-
a.) has multiple i/p and single o/p
b.) has multiple i/p and multiple o/p
c.) has multiple i/p and multiple o/p
d.) has single i/p and single o/p
101. Which of the following best describes the authour`s attitude toward fairy tales ?
a.) fascination
b.) open approval.
c.) Indulgent tolerance.
d.) Scornful.
102. What type of sentence is this ?
Hurray! We won the match
a.) Exclamatory
b.) assertive
c.) Negative
d.) Affirmative
103. Before which of the following word will you put ‘a’
a.) hour
b.) M. A.
c.) Umbrella
d.) Man
104. The noun form of ‘fresh’ is –
a.) freshly
b.) freshen
c.) fresheners
d.) fresh itself
105. The word ‘clang’ is an example of –
a.) Simile
b.) inversion
c.) onomatopoeia
d.) irony
106. The Forbes magazine acclaimed Azim Premji as richest India’s is the chairman of-
a.) Pentafour software
b) Infosys
c.) IBM
d.) Wipro
107. Bharat Ratna award for the year 2001 goes to-
a.) Lata Mangeshkar and Zakeer Hussain
b.) Zakeer Hussain and Bismillah Khan
c.) Bismillah Khan and Lata Mangeshkar
d.) Lata Mangeshkar and Ustad Amzad Ali Khan
108. Mr. George W-Bush takes over as —— President of the united states of America succeeding Mr. Bill Clinton-
a.) 42nd
b.) 43rd
c.) 40th
d.) 45th
109. New Chief Minister of Pondicherry is-
a.) T. Venkat Naidu
b.) K. Hari Harh
c.) N. Rengaswany
d.) M. Mudliar
110. No court has the jurisdiction to interfere with the election process once set in motion by the Election commission. This
is enshrined in Article-
a.) 311
b.) 329
c.) 356
d.) 365
111. Ostrich is a-
a.) Running bird
b.) Flying bird
c) Swimming bird
d.) Migratory bird
112. The main atmospheric gas responsible for green house is-
a.) Oxygen
b.) Nitrogen
c.) Ozone
d.) Carbon-dioxide
113. Which of the following is not a Kharif Crop-
a.) Rice
b.) groundnut
c.) Sugarcane
d.) gram
114. The function of World Bank is to-
a.) Help in reconstruction and development of world economy
b.) Facilitate poor countries to trade on concessional rates
c.) Promote growth of international trade and equilibrium in balance of payments
d.) Ease trade barriers and establish rule of fair trade
115. Speed of sound is maximum in-
a. )Water
b.) Air
c.) Steel
d.) Vacuum
116. “Long years ago we made a trust with destiny.” Whose words are these-
a.) Subhash Chandra Bose
b.) Jawaharlal Nehru
c.) Lajpat Rai
d.) Bhagat Singh
117. Durand cup is associated with-
a.) Hockey
b.) Tennis
c.) Football
d.) Badminton
118. Rabindranath Tagore was awarded the Nobel Prize in literature in the year.
a.) 1908
b.) 1910
c.) 1913
d.) 1914
119. India successfully conducted its first underground nuclear experiment at Pokhran in Rajas than on-
a.) May 18, 1975
b.) May 20, 1974
c) May 17, 1974
d.) May 17, 1974
120. An emergency loan of $ 500 million to help reconstruct infrastructure in earth quake devastated Gujarat approved by-
a.) Asian development Bank
b.) World Bank
c.) Swiss Bank
d.) Reserve Bank of India
which of the following will have least value in ohms-
a.) Resistance
b.) Reactance
c.) Impedance
d.) None
2 Oscillator crystal are made of –
a.) Silicon
b.) Germanium
c.) Quartz
d.) None
3. For small size, high frequency coils, the most common core material is-
a. )Air
b. )Ferrite
c.) Powdered ion
d.) Steel
4. If we have a parallel plate capacitor of plate area ‘A’ and plate separatoin t and having a capacity C and a metallic
plate r of area A and of negligible thickness is introduced in the capacitor at a distance from either of the two plates as
shown in the given figure then the capacity of the capacitor will become –
a.)
b.)C
c.)2C
d.)4C
5. A superconductor is a –
a.)A material showing perfect conductivity and Meissner effect below a critical temperature
b.)A conductor having zero resistance
c.)A perfect conductor with highest di-magnetic susceptibility
d.)A perfect conductor which becomes resistance when the current density through it exceeds a critical value
6. When an inductor tunes at 200 KHz with 624 pF capacitor and at 600 KHz with 60.4 pF capacitor then the self capacitance of
the inductor would be –
a)8.05 pF
b)10.05pF
c.)16.01pF
d.)20.01pF
7. Sparking occur when a load is switched off because the circuit has high –
a.)Inductance
b.)Capacitance
c.)Resistance
d.)None
8. Sparking between contacts can be reduced by inserting a –
a.)Resistance in the line
b.)Capacitor in series with contacts
c.)Capacitor in parallel with contacts
d.)None
9. RF amplifier of an A.M. receiver is normally biased in –
a.)Class ‘A’
b.)Class ‘b’
c.)Class ‘C’
d.)None
10. The value of gate voltage for the operation of enhancement of only N channel MOSFET has to be –
a.)High positive
b.)High negative
c.)Low positive
d.)Zero
11. The input gate current of a FET is –
a.)a few microamperes
b.)negligibly small
c.)a few milliamperes
d.)a few amperes
12. In the following fig. with R = 30k, the value of current through 2 K resistor is –
a.)25 mA
b.)40 mA
c.)25/16 mA
d.)10 mA
13. A step recovery diode –
a.)has on extremely short recovery time
b.)conducts equally well in both directions
c.)is mainly used as a harmonic generator
d.)is an ideal rectifiers of high frequency signals
14. In order to get maximum undistorted output signal from CE amplifier with VCC 10V, the value of VCE (Q) should be
approximately-
a.)0.1V
b.)5V
c.)10V
d) V
15. In a FET the electrode, which corresponds to collector in bipolar transistor, is –
a.)source
b.)drain
c.)gate
d.)none
16. The device which acts like an NPN and a PNP transistor connected base to base and emitter to collector is –
a.)Triac
b.)UJT
c.)Diac
d.)SCR
17. A typical optical fibre has –
a.)High refractive index core and low refractive index cladding
b.)Low refractive index core and high refractive index cladding
c.)Both a and b
d.)None
18. In the following figure circuit diagram of an op-amp based is shown. The ratio is equal to –
a.)9
b.)11
c.)10
d.)21
19. When a loud speaker is connected across the terminals A and B of the network shown in the fig. then its impedance to
obtain maximum power dissipation in it will be –
a.)3 – j1
b.)3 + j9
c.)7.5 + j 2.5
d.)7.5 – j 2.5
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20. In the lattice network, the value of R for the maximum power transfer to the load –
a.)5
b.)6.5
c.)8
d.)9
21. For a lossy transmission line short circuited at the receiving end, the input impedance is given by (Z0 is the
characteristic impedance, Ö is the propagation constant and l is the length of the line-
a.)Z0 cot h Öl
b.)Z0 cot Öl
c.)Z0 tan h.Ö l
d.) Z0 tan Öl
22. The approximate thickness of the radome wall should be –
a.)l
b.)l/4
c.)l/2
d.)l/
23 A relatively permanent information is stored in
a. )ROM
b.)RAM
c.)PROM
d.)Volatile memory
24. The rise time of the RC network shown in the given figure is approximately equal to –
b.) RC
c.) 2RC
d.) 4RC
25. If in the network shown in the fig. initially a steady state is attained by closing the switch ’s’ and then if the switch
is opened at t = 0, then the current i(t) through the inductor will be –
a.) cos50tA
b.) 2A
c.) 2cos100tA
d.) 2sin50tA
26. When the p network of figure – I and T-network of figure – II are equivalent then the values of R1, R2 and R3 will be
respectively –
a) 9W, 6W and 6W
b.) 6W, 6W and 9W
c.) 9W, 6W and 9W
d.) 6W, 9W and 6W
27. When the impedance matrices of a two port networks are given by and , then if these two networks are connected in series
then the impedance matrix of the resulting two-port network will be –
d.) indeterminate
28. Joule/coulomb is the unit of -
a.) Electric field potential
b.) Potential
c .) Charge
d.) None of the above
29. The electric field line and equipotential lines-
a.) Are parallel to each other
b.)Are one and same
c.) Cut each other orthogonally
d.)Can be inclined to each other at any angle
30. For a lossy transmission line short circuited at the receiving end, the input impedance is given by (When Z0 is the
characteristic impendence g is the propagation constant and L is the length of the line
31. When two equal positive point charges are placed along X- axis at X1 and –X1 respectively then the electric field vector
at a point P on the positive Y-axis will be directed-
a.) In the +x direction
b.) In the –x direction
c. ) In the +y direction
d.) In the –y direction
32. The directions of and in TEM mode transmission line with respect to the direction of propagation are-
a.) Both and are transverse to the direction of propagation
b.) is and are transverse and h has a component in the direction of propagation
c.) is entirely transverse and has a component in the direction of propagation
d.) is entirely transverse and has a component in the direction of propagation
33. The lowest TM mode in a rectangular waveguide of cross –section a x b with a>b will be-
a.) TM01
b.)TE10
c.) TM112
d.)TE11
34. When a transmitter in a free space radiates a mean power of ‘p’ watts uniformly in all directions then at a distance d
sufficiently far from the source in plane the electric field E should be related to p and d as –
35. When a dipole antenna was radiating with some excitation in free space radiating a certain amount of the power v if then
this antenna is immersed in a lake where water is non-dissipative but has a dielectric constant of 81, then the radiated
power with the same excitation will be
a.) Decrease to finite non-zero value
b.)Remain the same
c. )Increase
d.)Decrease to zero
36. When a (75 – j40)W load is connected to a coaxial line of Z0 = 75 W at 6MHz then the load matching on the line can be
accomplished by connecting-
a.) A short – circuited stub at the load
b.)An inductance at the load
c. )A short circuited stub at a specific distance from the load
d.)none of the above
37. As compared to analog multimeters, digital multimeters are –
a.) less accurate
b.) more accurate
c.) equally accurate
d.) none.
38. When a signal of 10 mV at 75 MHz is to be measured then which of the following instruments can be used –
a.) VTVM
b.) Cathode ray oscilloscope
c.) Moving iron voltmeter
d.) Digital multimeter
39. Which of the following statement is true about two wattmeter method for power measurement in three phase current ?
a.) power can be measured using two wattmeter method only for star connected three phase circuits.
b.) when two meter show indentical readings, in the power factor is 0.5.
c.) when power factor is unit, one of the wattmeter reads zero
d.) when the reading of the two wattmeters are equal but of opposite sign, then the power factor is zero –
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40. When a capacitance transducer has two plates of area 5cm2 each, separated by an air gap of 2mm than the displacement
sensitivity in pf/cm due to gap change would be –
a.) 11.1
b.) 44.2
c.) 52.3
d.) 66.3
41. The Q of a radio coil –
a.) is independent of frequency
b.) increases monotonically as frequency increases
c.) decreases monotonically as frequency increases
d.) increases upto a certain frequency and then decreases beyond that frequency
42. When a generator of internal impedance and operating at 1GHz feeds a load via a coaxial line of characteristic impedance
50 ohm then the voltage wave ratio on the feed line is –
a.) 0.5
b.) 1.5
c.) 2.5
d.) 1.75
43. The coding system typically used in digital telemetry is –
a.) PPM (pulse position modulation)
b.) PAM (pulse amplitude modulation)
c.) PCM (pulse code modulation)
d.) PDM (pulse duration modulation)
44. Radiation pyrometers are used for the measurement of temperature in the range of –
a.) -2000C to 5000C
b.) 00C to 5000C
c.) 5000C to 12000C
d.) 12000C to 25000C
45. In the given figure band structure is shown. It is of –
a.) Gallium Avesenide (GaAs)
b.) Silicon (Si)
c.) Copper (Cu)
d.) Germanium (Ge)
46. When anode is positive with respect to cathode in an SCR, the numbers of blocked p-n junction is –
a.) 1
b.) 2
c.) 3
d.) 4
47. The circuit symbol for a GTO is
a. b.
c. d.
48. In the given fig. mark out the type of Cyclo converters
a.) 1 phase to 1 phase with continuous conduction
b.) 1 phase to 1 phase with discontinuous conduction
c.) step up device
d.) 3 phase to 1 phase device
49. In the given fig. A-1, C=5, m H and C=20 m F, C is initially charged to 200 V. After the switch.
S is closed at t = 0 the
maximum value of current and the
time at which it reaches this value are respectively.
a.) 400 A, 15.707 mS
b.) 50 A, 30 mS
c.) 100 A, 62.828 mS
d.) 400 A, 31.414 mS
50. In the given circuit the maximum current in the main SCR M can be-
a.) 200 A
b.) 170.7 A
c.) 141.4 A
d.) 70.7 A
51. The transfer function of an amplifier is given by
The high 3-db frequency of the amplifier will approximately
a.) 5850 KHZ
b.)585 KHZ
c.) 5850 HZ
d.)585HZ
52. In comparison to full wave rectifier with two diodes the four divide bridge rectifier has the dominant advantage of -
a). Higher current carrying
b.)Lower ripple factor
c.) Higher efficiency
d.)Lower peak increase voltage require
53. Power output increase in a class-c amplifier-
a.) If the conduction angle decrease
b).If the conduction angle increase
c.) Are not governed by the conduction angle
d.)None of the above
54. A transistor with hie = 1.5 k and hfe = 75 is used in an emitter follower circuit where R1 and R2 are used for normal
biasing . Approximate value of it’s current amplification is-
a.)75
b.)76
c.)75/76
d.)-75
55. Amplifier of class B has high theoretical efficiency of 78.5 percent because-
a.) It is biased almost to saturation
b.)Its quiescent current is low
c.)It’s output is an exact replica of it’s input
d.)It is biased well below cut off
56. The coupling that produces minimum interference with frequency response is-
a.) Direct coupling
b.)Impedance coupling
c.) R C coupling
d.)Transformer coupling
57. In the circuit shown in the given figure Rf provides
a.) Current series feedback
b.)Current shunt feedback
c.) Voltage series feedback
d.)Voltage shunt feedback
58. Mark the correct relation for the junction transistor
59. Data in the serial form can be converted into parallel form by using –
a.) PISO shift register
b.) SOIP shift register
c.) SIPO shift register
d.) POIS shift register
60. PROMs are used to store-
a.) bulk information
b.) information to be accessed rarely
c.) sequence information
d.) relatively permanent information
61. The horizontal axis in a 3 bit unipolar D/A converter represents-
a.) Output bit combination
b.) analog output voltage
c.) input bit combination
d.) none of the above
62. ‘Not allowed’ condition in NAND gate SR flip flop is –
a.) s = 0, R = 0
b.) s = 1, R = 1
c.) s = 0, R = 1
d.) s = 1, R = 0
63. Name the fastest logic family-
a) TTL
b. RTL
c.) DCTL
d.) ECL
64. Equation corresponding to De Morgan’s theorem in Boolean Algebra is –
a.) (A+B) (A+B) = AA + AB + BA + BB
c.) A + AB = A
d.) None of the above
65. In the given fig find radix of the system –
a.) 2b.) 4
c.) 6
d.) 8
66. Modems are used for data transmission telephone lines to –
a.) increase the transmission capacity
b) improve noice performance
c.) incorporate error control coding
d.) eliminate dc component in the transmitted signal
67. The figure of a control system is shown. The maximum value of gain K for which the system is stable is-
a.)
b.) 3
c.) 4
d.) 5
68. Identify the example of open-loop system-
a.) A windscreen wiper
b.) Aqualung
c.) Respiratory system of an animal
d.) A system for controlling Anti-rocket missiles.
69. Consider the following expressions indicating the step or impulse response of an initially relaxed control system-
1. (5 – 4e-2+) u(t)
2. (e-2t +5) (u(t))
3 .V(t) + 8e-2t u(t)
4 . V(t) + 4e-2t 4(t)
Those which correspond to the step and impulse response of the same system include-
a.) 1&3
b.) 1&4
c.) 2&4
d.) 1&4
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70. A system is described by
To test its stability by Lyapunov’s method the following V functions are considered.
Mark the most suitable V-function in this case-
a.) Only V1
b.)Only V2
c.) Both V1 and V2
d.) Neither V1 nor v2
71. Identity the polar plot of a typical type zero system with open loop transfer function
72. The scattering matrix of a magic –tee shown in the given figure is-
73. Which is the following relate to rational transfer function of a system-
1. Ratio of Fourier transform of output to input with zero initial conditions.
2. Ratio of Laplace transform of output to input with zero initial conditions.
3. Laplace transform of system impulse response.
4. Laplace transform of system unit step response select the correct answer using the codes given below.
Codes
a.) 1 and 4
b.) 2 and 3
c.) 1 and 3
d.) 2 and 4
74. For the signal g (t) – 10 cos (50 pt) cos2 (150at)
The Nyquist sampling state in t seconds is
a.) 150 samples per second
b.) 200 samples per second
c.) 300 samples per second
d.) 350 samples per second
75. In the case of a 70 MHz 1F carries for a transponder band width of 36 MHz; energy must lie between – MHz.
a.) 34 and 106
b.) 52. And 88
c.) 106 and 142
d.) 34 and 142
76. Radar used to eliminate clutter in navigational application is –
a.) Pulse radar
b.) Tracking radar
c.) MTI radar
d.) Mono pulse radar
77. The 1.55 mm windows is not yet in use with fiber optic systems because –
a.)The attenuation is higher than at 0.85 mm
b) The attenuation is higher than at 1.3mm
c.) Suitable laser devices have not yet been developed
d.) It does not lend itself to wavelength multiplexing
78. Pre-emphasis in FM systems involves-
a.) Compression of the modulating signal
b.) Expansion of the modulating signal
c.) Amplification of lower frequency components of the modulating signal.
d.) Amplification of higher frequency components of the modulating signal.
79. In a terrestrial microwave system transmission of signals is achieved through-
a.) reflection from the ionosphere
b.) line of sight mode
c) reflection from the ground
d.) diffraction from the stratosphere.
80. Casse grain feed is used with a parabolic reflector to
a.) increase the gain of the system
b). increase the bandwidth of the system
c.) reduce the size of the main reflector
d.) allow the feed to be placed at a convenient point.
81. In most microwave communication link rain drop attenuation is caused due to-
a.) scattering of microwaves by water drops of specific size.
b) scattering of microwaves by a collection of droplets acing as a single body.
c.) absorption of microwaves by water and consequent heating of the liquid
d.) absorption of the microwaves by water vapor in the atmosphere.
82. Circuit in the given figure represents. –
a.) an astable multivibrator
b.) A monostable multivibrator
c.) Voltage controlled oscillator
d.) Ramp generator
83. . D = r is-
a.) Maxwell’s 1st equation
b.) Maxwell’s II equation
c.) Maxwell’s III equation
d.) Maxwell’s IV equation
84. In a rectangular wave-guide which TM mode exists-
a.) TM00
b.) TM01
c.) Tm10
d.) TM11
85. In directional coupler a portion of power two velliry fram port 1) to port 2) is coupled to.
a). port 4
b). port 3
c. port 2.
d.) port 3 & 4.
86. For high power i.e. 10 w to 50 kw measurement –
a.) Barometer are used
b.) Thermisters are used
c.) Calorimetric technique
d.) Calorimetric watt meter technique used
87. The difference between TWT & klystron is –
a.) In TWT electrons are in contact with RF field for long time & in klystron for short time
b.) In klystron electrons are in contact with RF field for long time & in TWT for short time
c.) In klystron there is no contact in RF field & electrons while in TWT there is contact
d.) In TWT phase is no contact is RF field & electrons while in klystron there is contact
88. Which one is most suitable for transmission through wave guide-
a.) Hown antennas
b.) Bioconical antennas
c.) helical antenna
d. Discone
89. The skip distance of microwave is given by –
a.)
b.)
c.)
d.)
90. How many general purpose registers 8085mp-
a.) 4
b.) 6
c.) 8
c.) 10
91. 8085 mP has no. of addressing modes-
a.) 2
b.) 3
c.) 4
d.) 5
92. What will be status of z and c y flag after execution of SUB A instruction
a.) z = 0, cy = 0
b.) z = 0, cy = 1
c.) z = 1, cy = 0
d.) z = 1, cy = 1
93. Microprocessor accept interrupt only if.
a.) interrupt flip flop disabled.
b.) when INTA signal is low.
c. interrupt flip flop enabled.
d.) none of above.
94. Microprogramming is a technique
a.) for programming the microprocessor
b.) for writing small programs efficiently
c.) for programming the control steps of computer
d.) for programming o/p / i/p
95. High level programs like C are converted into machine language with the help of
a.) interpreter
b.) compiler
c.) operating
d.) system
96. (10110011)2 = (?)8
a.) 253
b.) 263
c.) 273
d.) 283
97. A Not gate at the output of AND gate converts AND gate into-
a.) NAND
b.) NOR
c.) AND
d.) NOPE.
98. The O/P of a logic gate is the gate must be-
a.) AND
b.) OR
c.) NAND
d.) X-OR
99. 38. A symbol of JK flip flop is-
BSNL Free download previous years 2007 2008 2009 recruitment question papers for GE JTO exam sample papers. Answer keys /
solutions coming soon!
100. A demultiplener-
a.) has multiple i/p and single o/p
b.) has multiple i/p and multiple o/p
c.) has multiple i/p and multiple o/p
d.) has single i/p and single o/p
101. Which of the following best describes the authour`s attitude toward fairy tales ?
a.) fascination
b.) open approval.
c.) Indulgent tolerance.
d.) Scornful.
102. What type of sentence is this ?
Hurray! We won the match
a.) Exclamatory
b.) assertive
c.) Negative
d.) Affirmative
103. Before which of the following word will you put ‘a’
a.) hour
b.) M. A.
c.) Umbrella
d.) Man
104. The noun form of ‘fresh’ is –
a.) freshly
b.) freshen
c.) fresheners
d.) fresh itself
105. The word ‘clang’ is an example of –
a.) Simile
b.) inversion
c.) onomatopoeia
d.) irony
106. The Forbes magazine acclaimed Azim Premji as richest India’s is the chairman of-
a.) Pentafour software
b) Infosys
c.) IBM
d.) Wipro
107. Bharat Ratna award for the year 2001 goes to-
a.) Lata Mangeshkar and Zakeer Hussain
b.) Zakeer Hussain and Bismillah Khan
c.) Bismillah Khan and Lata Mangeshkar
d.) Lata Mangeshkar and Ustad Amzad Ali Khan
108. Mr. George W-Bush takes over as —— President of the united states of America succeeding Mr. Bill Clinton-
a.) 42nd
b.) 43rd
c.) 40th
d.) 45th
109. New Chief Minister of Pondicherry is-
a.) T. Venkat Naidu
b.) K. Hari Harh
c.) N. Rengaswany
d.) M. Mudliar
110. No court has the jurisdiction to interfere with the election process once set in motion by the Election commission. This
is enshrined in Article-
a.) 311
b.) 329
c.) 356
d.) 365
111. Ostrich is a-
a.) Running bird
b.) Flying bird
c) Swimming bird
d.) Migratory bird
112. The main atmospheric gas responsible for green house is-
a.) Oxygen
b.) Nitrogen
c.) Ozone
d.) Carbon-dioxide
113. Which of the following is not a Kharif Crop-
a.) Rice
b.) groundnut
c.) Sugarcane
d.) gram
114. The function of World Bank is to-
a.) Help in reconstruction and development of world economy
b.) Facilitate poor countries to trade on concessional rates
c.) Promote growth of international trade and equilibrium in balance of payments
d.) Ease trade barriers and establish rule of fair trade
115. Speed of sound is maximum in-
a. )Water
b.) Air
c.) Steel
d.) Vacuum
116. “Long years ago we made a trust with destiny.” Whose words are these-
a.) Subhash Chandra Bose
b.) Jawaharlal Nehru
c.) Lajpat Rai
d.) Bhagat Singh
117. Durand cup is associated with-
a.) Hockey
b.) Tennis
c.) Football
d.) Badminton
118. Rabindranath Tagore was awarded the Nobel Prize in literature in the year.
a.) 1908
b.) 1910
c.) 1913
d.) 1914
119. India successfully conducted its first underground nuclear experiment at Pokhran in Rajas than on-
a.) May 18, 1975
b.) May 20, 1974
c) May 17, 1974
d.) May 17, 1974
120. An emergency loan of $ 500 million to help reconstruct infrastructure in earth quake devastated Gujarat approved by-
a.) Asian development Bank
b.) World Bank
c.) Swiss Bank
d.) Reserve Bank of India
Monday, December 7, 2009
Power Sector Links
Power Sector Links
MoP - Ministry of Power
BBMB - Bhakra Beas Management Board
CEA - Central Electricity Authority
BEE - Bureau of Energy Efficiency
DVC - Damodar Valley Corporation
SJVN - Satluj Jal Vidyut Nigam Limited
NPTI - National Power Training Institute
NTPC - National Thermal Power Corporation
PGCIL - Power Grid Corporation of India Limited
CERC - Central Electricity Regulatory Commission
NEEPCO - North Eastern Electric Power Corporation Limited
NHPC - National Hydroelectric Power Corporation Limited
MoP - Ministry of Power
BBMB - Bhakra Beas Management Board
CEA - Central Electricity Authority
BEE - Bureau of Energy Efficiency
DVC - Damodar Valley Corporation
SJVN - Satluj Jal Vidyut Nigam Limited
NPTI - National Power Training Institute
NTPC - National Thermal Power Corporation
PGCIL - Power Grid Corporation of India Limited
CERC - Central Electricity Regulatory Commission
NEEPCO - North Eastern Electric Power Corporation Limited
NHPC - National Hydroelectric Power Corporation Limited
Rail way websites
Official Websites of Ministry of Indian Railway
Right to Information Act, 2005
Guidelines on Foreign Travel on official duty/training
Engineering Services Examination 2004
Engineering Services Examination 2004
Periodical Earnings and Freight Loading of Indian Railways
Classified List of Gazetted Establishment of Indian Railways
Railways Establishment Codes, Manuals and Circulars
Zonal Railways
South East Central Railway
Central Railway
East Central Railway
East Coast Railway
Eastern Railway
North Central Railway
North Eastern Railway
North Western Railway
North East Frontier Railway
Northern Railway
South Central Railway
South Eastern Railway
South Western Railway
Southern Railway
West Central
Western Railway
Production Units
Chittaranjan Loco Works
Deisel-Loco Modernisation Works
Diesel Locomotive Works
Integral Coach Factory
Rail Coach Factory
Rail Wheel Factory
Corporation sites
Central Organisation For Modernisation of Workshops
Centre for Railway Information System
Container Corporation of India Ltd.
Indian Railway Catering and Tourism Corporation Ltd.
Indian Railway Finance Corporation
IRCON International Ltd.
Konkan Railway Corporation's
Mumbai Railway Vikas Corporation
RAILTEL Corporation of India Ltd.
RITES Ltd.
Pipavav Railway Corporation Limited
Others
Rail Vikas Nigam Ltd.
Central Organisation for Railway Electrification
Delhi Metro Rail Corporation
Federation of Railway Officers Associations
Indian Railway Accounts Service Association
Indian Railway Accounting Reforms
Indian Railway Central Organisation for Telecom
Indian Railway Stores Services
Indian Railway Welfare Organisation
Indian Railways Institute of Electrical Engineering
Indian Railways Institute of Signal Engineering and Telecommunications
Institute of Rail transport
National Rail Museum sites
Palace on Wheels
Railway Board
Railway Recruitment Boards
Railway Staff College, Baroda
Research Design and Standards Organisation
Indian Railways Institute of Mechanical and Electrical Engineering
Darjeeling Himalayan Railways
Right to Information Act, 2005
Guidelines on Foreign Travel on official duty/training
Engineering Services Examination 2004
Engineering Services Examination 2004
Periodical Earnings and Freight Loading of Indian Railways
Classified List of Gazetted Establishment of Indian Railways
Railways Establishment Codes, Manuals and Circulars
Zonal Railways
South East Central Railway
Central Railway
East Central Railway
East Coast Railway
Eastern Railway
North Central Railway
North Eastern Railway
North Western Railway
North East Frontier Railway
Northern Railway
South Central Railway
South Eastern Railway
South Western Railway
Southern Railway
West Central
Western Railway
Production Units
Chittaranjan Loco Works
Deisel-Loco Modernisation Works
Diesel Locomotive Works
Integral Coach Factory
Rail Coach Factory
Rail Wheel Factory
Corporation sites
Central Organisation For Modernisation of Workshops
Centre for Railway Information System
Container Corporation of India Ltd.
Indian Railway Catering and Tourism Corporation Ltd.
Indian Railway Finance Corporation
IRCON International Ltd.
Konkan Railway Corporation's
Mumbai Railway Vikas Corporation
RAILTEL Corporation of India Ltd.
RITES Ltd.
Pipavav Railway Corporation Limited
Others
Rail Vikas Nigam Ltd.
Central Organisation for Railway Electrification
Delhi Metro Rail Corporation
Federation of Railway Officers Associations
Indian Railway Accounts Service Association
Indian Railway Accounting Reforms
Indian Railway Central Organisation for Telecom
Indian Railway Stores Services
Indian Railway Welfare Organisation
Indian Railways Institute of Electrical Engineering
Indian Railways Institute of Signal Engineering and Telecommunications
Institute of Rail transport
National Rail Museum sites
Palace on Wheels
Railway Board
Railway Recruitment Boards
Railway Staff College, Baroda
Research Design and Standards Organisation
Indian Railways Institute of Mechanical and Electrical Engineering
Darjeeling Himalayan Railways
Saturday, December 5, 2009
Test paper
Q1 Which of the following has high electrical resistivity
(a) Copper (b) Gold (c) Carbon (d) Silver
Q2 The resistance of 200 m. long circular copper wire is 21Ω.If its thickness is 0.44mm,What is the resistivity(ohm-m) of the copper is
(a) 1.597*10-8 (b) 2.507*10-8 (c) 5.597*10-6 (d) None of these
Q3 Metals have temperature coefficient of resistance
(a) Positive (b) negative (c) May be positive or Negative (d) None of these
Q4 The resistance of two wire is 25Ω when connected in series and 6Ω when connected in parallel.The resistance of each wire is
(a) 12 &13Ω (b) 15&10Ω (c) 20& 5 Ω (d) 24&1Ω
Q5 A current of 3A flows through 10Ω resistor. The energy dissipated in 5sec.is
(a) 450J (b) 150J (c) 250J (d) None of these
Q6 Ideal current source has its internal resistance equal to
(a)1Ω. (b)2Ω. (c) 0Ω (d) InfiniteΩ
Q7 If resistance of all three branches of star connected load is 1Ω each, then the resistance of each branch of equivalent delta load would be
(a) 3Ω (b) 9Ω (c) 0.3Ω (d) 1/3Ω
Q8 A p.d. of 300V is maintained across the terminals of the capacitor. The electric field strength(kV/m) between the plate gap of (0.3mm) is
(a) 1000 (b) 2000 (c) 3000 (d) 4000
Q9 An 8micro-farad capacitor is connected in series with 0.5MΩ resistor. The time constant of the RC circuit is
(a) 16sec. (b) 6sec (c) 5sec (d) 4sec
Q10 An 8micro-farad capacitor is charged from a 100V supply. The energy stored in the capacitor is
(a) 0.004J (b) 0.0016J (c) 0.008 J (d) None of these
Q11 A conductor carries a current of 100A at right angle to a magnetic field having density of 0.5 T. The force on per unit lengh of the conductor is
(a) 50N (b) 500N (c) 150N (d) 5.0N
Q12 A magnetic flux of 200μwb passing through a coil of 1200 turns is reversed in 0.2sec.The induced emf in the coil is
(a) 12V (b) 2.4V (c) 2.2V (d) 1.2V
Q13 The value of 1/√(μ0 ε0) is equal to
(a) Speed of light (b) 1/ Speed of light (c) (Speed of light )2 (d) None of these
Q14 A inductance (L) of coil is given by
(a) NΦ/I (b) NI/Φ (c) I /ΦN (d) None of these
Q15 A coil of 200 turns is wound on a non-magnetic circular core of area 500mm2& the mean circumference of 400mm.The inductance of coil is
(a) 628H (b) 6.28μH (c ) 62.8μH (d) None of these
Q16 An alternating voltage is given by the equation v = 200Sin 314t the rms value of the voltage is
(a) 141.42V (b) 282.82V (c) 14.142V (d) None of these
Q17 In a transformer the induced emf in the winding is given by (notation used have their usual meaning)
(a) E = 1.11 N f Φm (b) E = 2.22 N f Φm (c) E = 4.44 N f Φm (d) None of these
Q18 A dc motor takes an armature current of 10A at 220V.The armature resistance of the machine is 0.2Ω, flux per pole is .01wb, the no of poles are 6,and the armature has wave wound 480 conductors. The torque developed in armature is
(a) 100Nm (b) 25Nm (c) 44Nm (d) 22.91Nm
Q19 A,3-phase, synchronous generator has 4 pairs of pole is running with the speed of 900 rpm.The frequency of the supply would be
(a) 50Hz (b) 60Hz (c) 25Hz (d) 150Hz
Q20 The advantage of permanent magnet moving coil(PMMC) instrument is
(a)Low power consumption (b) No hysteresis loss
(c) Efficient eddy current damping (d) All of the above
Q21 The majority charge carrier in p-type semiconductor are
(a) Electrons (b) Holes (c) Both Electrons and Holes (d) None of these
Q22 An n-type semiconductor as a whole is
(a) Electrically +ve (b) Electrically –ve (c) Electrically neutral (d) None of these
Q23 The out put of the logic gate is one, only when all the inputs are one. Then logic gate is
(a) AND (b) OR (c) NAND (d) NOR
Q24 In a transistor which of the following region is very lightly doped
(a) Emitter (b) Collector (c) Base (d) None of these
Answers
1 c
2
3 a
4 b
5 a
6 d
7 a
8
9 d
10 d
11 a
12 d
13 a
14 a
15
16 a
17 c
18 d
19 b
20
21 b
22 c
23 a
24 c
(a) Copper (b) Gold (c) Carbon (d) Silver
Q2 The resistance of 200 m. long circular copper wire is 21Ω.If its thickness is 0.44mm,What is the resistivity(ohm-m) of the copper is
(a) 1.597*10-8 (b) 2.507*10-8 (c) 5.597*10-6 (d) None of these
Q3 Metals have temperature coefficient of resistance
(a) Positive (b) negative (c) May be positive or Negative (d) None of these
Q4 The resistance of two wire is 25Ω when connected in series and 6Ω when connected in parallel.The resistance of each wire is
(a) 12 &13Ω (b) 15&10Ω (c) 20& 5 Ω (d) 24&1Ω
Q5 A current of 3A flows through 10Ω resistor. The energy dissipated in 5sec.is
(a) 450J (b) 150J (c) 250J (d) None of these
Q6 Ideal current source has its internal resistance equal to
(a)1Ω. (b)2Ω. (c) 0Ω (d) InfiniteΩ
Q7 If resistance of all three branches of star connected load is 1Ω each, then the resistance of each branch of equivalent delta load would be
(a) 3Ω (b) 9Ω (c) 0.3Ω (d) 1/3Ω
Q8 A p.d. of 300V is maintained across the terminals of the capacitor. The electric field strength(kV/m) between the plate gap of (0.3mm) is
(a) 1000 (b) 2000 (c) 3000 (d) 4000
Q9 An 8micro-farad capacitor is connected in series with 0.5MΩ resistor. The time constant of the RC circuit is
(a) 16sec. (b) 6sec (c) 5sec (d) 4sec
Q10 An 8micro-farad capacitor is charged from a 100V supply. The energy stored in the capacitor is
(a) 0.004J (b) 0.0016J (c) 0.008 J (d) None of these
Q11 A conductor carries a current of 100A at right angle to a magnetic field having density of 0.5 T. The force on per unit lengh of the conductor is
(a) 50N (b) 500N (c) 150N (d) 5.0N
Q12 A magnetic flux of 200μwb passing through a coil of 1200 turns is reversed in 0.2sec.The induced emf in the coil is
(a) 12V (b) 2.4V (c) 2.2V (d) 1.2V
Q13 The value of 1/√(μ0 ε0) is equal to
(a) Speed of light (b) 1/ Speed of light (c) (Speed of light )2 (d) None of these
Q14 A inductance (L) of coil is given by
(a) NΦ/I (b) NI/Φ (c) I /ΦN (d) None of these
Q15 A coil of 200 turns is wound on a non-magnetic circular core of area 500mm2& the mean circumference of 400mm.The inductance of coil is
(a) 628H (b) 6.28μH (c ) 62.8μH (d) None of these
Q16 An alternating voltage is given by the equation v = 200Sin 314t the rms value of the voltage is
(a) 141.42V (b) 282.82V (c) 14.142V (d) None of these
Q17 In a transformer the induced emf in the winding is given by (notation used have their usual meaning)
(a) E = 1.11 N f Φm (b) E = 2.22 N f Φm (c) E = 4.44 N f Φm (d) None of these
Q18 A dc motor takes an armature current of 10A at 220V.The armature resistance of the machine is 0.2Ω, flux per pole is .01wb, the no of poles are 6,and the armature has wave wound 480 conductors. The torque developed in armature is
(a) 100Nm (b) 25Nm (c) 44Nm (d) 22.91Nm
Q19 A,3-phase, synchronous generator has 4 pairs of pole is running with the speed of 900 rpm.The frequency of the supply would be
(a) 50Hz (b) 60Hz (c) 25Hz (d) 150Hz
Q20 The advantage of permanent magnet moving coil(PMMC) instrument is
(a)Low power consumption (b) No hysteresis loss
(c) Efficient eddy current damping (d) All of the above
Q21 The majority charge carrier in p-type semiconductor are
(a) Electrons (b) Holes (c) Both Electrons and Holes (d) None of these
Q22 An n-type semiconductor as a whole is
(a) Electrically +ve (b) Electrically –ve (c) Electrically neutral (d) None of these
Q23 The out put of the logic gate is one, only when all the inputs are one. Then logic gate is
(a) AND (b) OR (c) NAND (d) NOR
Q24 In a transistor which of the following region is very lightly doped
(a) Emitter (b) Collector (c) Base (d) None of these
Answers
1 c
2
3 a
4 b
5 a
6 d
7 a
8
9 d
10 d
11 a
12 d
13 a
14 a
15
16 a
17 c
18 d
19 b
20
21 b
22 c
23 a
24 c
Wednesday, December 2, 2009
Tuesday, December 1, 2009
APGENCO SUB ENGINEER,S ELECTRICAL AND ELECTRONICS ENGINEERING
ELECTRICAL AND ELECTRONICS ENGINEERING
1. ELEMENTS OF ELECTRICAL ENGINEERING :
a. Comprehend basic principles of electricity.
b. Know the magnetic effects of electric current.
c. Understand electromagnetic induction.
d. Understand electric charge and electrostatic field.
2. ELECTRICAL CIRCUITS:
a. Understand Kirchoff`s laws and star delta Transformations and Network Theorems.
b. Comprehend the relationship between quantities connected with alternating current.
c. Comprehend the single phase A.C. Circuits.
d. Poly Phase Circuits.
3. D.C. MACHINES:
a. Fundamentals of D.C. Generators.
b. Armature Reaction and Characteristics of D.C. Generator.
c. Fundamentals of D.C. Motors.
d. Speed Control and Starters for D.C. Motors.
e. Characteristics and Testing of D.C. Motors.
4. ELECTRICAL MEASURING INSTRUMENTS & BATTERIES:
a. Know the classification of different measuring instruments.
b. Understand the construction and working of different electrical measuring instruments.
c. Understand the method of measurement of resistance.
d. Transducers and Sensors
e. Understand Batteries
5. A.C MACHINES:
a. Understand the working of Single Phase Transformers.
b. To understand Three Phase Transformers.
c. Know the classification, construction, working and testing of alternators.
d. Comprehend the procedure for voltage control and synchronization.
e. Comprehend the working of synchronous motors.
f. Comprehend the working of three phase induction motor.
g. Comprehend the working of single Phase induction motor.
h. Comprehend the working of single Phase commutator motor.
6. POWER SYSTEMS:
a. Understand the various sources of Power Generation.
b. Understand working of Thermal Power Station.
c. Understand Hydroelectric Power Station.
d. Understand the working of Nuclear & Gas Power Stations.
e. Comprehend combined operation and economics of power stations.
f. Comprehend the need for transmission and choice of supply system.
g. Line structure for transmission and distribution.
h. Underground Cables.
i. Understand different types of switchgear, fuses and reactors and their working
j. Protective relays.
k. Protection of alternators, transformer and transmission line.
l. Lighting arrestors and neutral grounding.
7. ELECTRONICS:
a. Passive Components (Resistors, Capacitors and Inductors).
b. Know the semi-conductor Devices.
c. Understand the working principle of Power supply circuits.
d. Understand the performance of Special Devices.
e. Understand the principle of Working of Amplifiers.
f. Understand the Principle of Working of Small Signal Amplifiers.
g. Understand the principle of working of Amplifiers.
h. Understand the Principle of Oscillators.
i. Appreciate the need for Modulation and Demodulation.
j. Electronic instruments and Industrial Applications.
k. Know the Basics of ICs.
l Know the basics of digital electronics.
m. Understand the working of combination logic circuits.
n. Understand the working of sequential logic circuits
o. Understand working of registers and memories.
8. ELECTRICAL UTILIZATION AND TRACTION:
a. Understand the principles of lighting.
b. Understand Principle of electric heating, welding and its industrial application.
c. Electric traction systems.
9. GENERAL MECHANICAL ENGINEERING:
a. I.C. Engines – Boilers – Turbines.
b. Understand the working of the centrifugal pumps.
10.INFORMATION TECHNOLOGY.
a. Understand the features of MS-word
b. Understand working with MS-Excel
c. Understand MS-Power point
d. Understand working with MS-Access.
11. INDUSTRIAL MANAGEMENT AND ENTREPRENEURSHIP:
a. Understand the principles of management as applied to industry.
b. Know the organization structure of an industry and the behavior of an individual in an organization.
c. Understand the different aspect of production management.
d. Understands the role of material management industries.
e. Understand marketing, sales and feasibility study.
f. Comprehend the provisions of industrial legislation in India and safety procedures.
g. Understand ISO 9000 and TQM
h. Understand the role of entrepreneur in economic development and in improving the quality of life.
Thursday, November 19, 2009
Sunday, November 15, 2009
HAL 12 November 2008
Question
Answer
Question………………………
In phase controlled rectifiers PF
V(rms)/Vs
An SCR has half cycle surge current rating of 3000A for 50Hz. One cycle surge current will be?
I2t=I2subT
I=Isub*√(T/t)
t=total time period
T=half time period
A step-up chopper is feed from a 220v dc source to deliver a load voltage of 66o v.If the non conducting time is 100micro-sec then required pulse width will be.
Vin/(1-D)=Vout
220/(1-D)=660
D=2/3
Toff=Ton(1-D)
Ton=300 Micro sec
Good transformer oil contains how much amount of water in ppm?
8PPM
Lightning over voltage create how much volt?
Lightning over voltage depends upon the magnitude of lightning (KV)
K/s(s+1)(s+5) then find out the value of K so that system become stable
S3+6S2+5S+k----CE
Apply routh hurwitz criteria
S3 1 5
S2 6 K
S1 (30-k)/6
S0 K
(30-k)/6>0
30-K>0
k<30
If a square waveform is given to the supply side of a 2wdg transformer its
o/p waveform will be
Triangular Wave
SC test done on transformer
To find Out the Copper losses And Series Parameters
If a transformer is operating in .8 PF lag & at efficiency of .9
if now P is .8 lead the efficiency will become
0.9 Only Because Efficiency curve is Single valued cure
Dielectric strength of air is?
30 kv/cm peak or 21.1 kv/cm rms
The voltage of a generator and an infinite bus are given
0.92, 10 deg & 1.0, 0 deg respectively the generator acts as a
Synchronous generator
A wave will not experience any reflection when impedance of line is equal to
Surge impedance
400 ohms for over head lines
40 to 50 ohms for cables
Power transmitted is related to system voltage as
P=EV/Xs Sinδ
Surge wave is attended by
Resistor
In galvanometer damping is provided by
Mechanical and electromagnetic
Megger is used for
Measurement of Very high resistance like insulation resistance of the cable etc
Its working principle is based on moving coil
AC is applied against a moving coil meter it will read
Zero if frequency is high
Oscillate around zero if frequency is low
Rectifier type instrument measures what value
RMS
Advantage of electrostatic instrument is
More accurate
Loading effect is low
Fast response etc.
Creeping occurs because
Over compensation due to frictional forces
Over voltage across pressure coil
Why 2 holes are drilled oppositely in disc of energy meter
To eliminate the creeping
Energy meter is_____ type equipment
Integrating / recording
Inductance is measured by which bridge
Maxwell’s, Anderson, Hay’s, Owen’s bridge
Which type of motor is used in refrigerator?
Capacitor Start and run Single phase induction motor
Corona’s advantage
To increases the virtual diameter of conductor
To protect the conductor from Switching over voltages
Reflection coefficient of current in open ended line is
-1
Reflection coefficient of voltage in open ended line is
1
Reflection coefficient of current in short circuit line is
1
Reflection coefficient of voltage in short circuit line is
-1
Calculation of making current when MVA & KV was given.
Making current=2.5*breaking current
Breaking current=MVA/KV
he o/p voltage e1 & e2 of 2 full-bridge inverters added using o/p transformer. In order to eliminate 5th harmonic from o/p voltage, the phase angle between e1&e2 will be-
36◦
A single phase fully controlled line commutated ac-dc converter operates as an inverter when-
α > 90◦
Why rotor of SCIM is skewed?
To eliminate the slot harmonics in the rotor
Magnetostriction is occurs in
AC circuits’ only
Interlopes are connected for?
To eliminate the Armature reaction
Identify type by pu value Xd”=0.3, Xd’=0.3, X0=0.6?
Transmission line
What to do for converting sine wave to triangular wave?
Integrating
Wave shape of armature mmf?
Triangular wave
Emf in a conductor is directly proportional to?
E α ΦZNP
What’s the order of Jacobin matrix for 20 no. of bus bar?
=2n-2
N=no of buses
=38
How many watt meters required to measure 3phase 4 wire system?
3
Answer
Question………………………
In phase controlled rectifiers PF
V(rms)/Vs
An SCR has half cycle surge current rating of 3000A for 50Hz. One cycle surge current will be?
I2t=I2subT
I=Isub*√(T/t)
t=total time period
T=half time period
A step-up chopper is feed from a 220v dc source to deliver a load voltage of 66o v.If the non conducting time is 100micro-sec then required pulse width will be.
Vin/(1-D)=Vout
220/(1-D)=660
D=2/3
Toff=Ton(1-D)
Ton=300 Micro sec
Good transformer oil contains how much amount of water in ppm?
8PPM
Lightning over voltage create how much volt?
Lightning over voltage depends upon the magnitude of lightning (KV)
K/s(s+1)(s+5) then find out the value of K so that system become stable
S3+6S2+5S+k----CE
Apply routh hurwitz criteria
S3 1 5
S2 6 K
S1 (30-k)/6
S0 K
(30-k)/6>0
30-K>0
k<30
If a square waveform is given to the supply side of a 2wdg transformer its
o/p waveform will be
Triangular Wave
SC test done on transformer
To find Out the Copper losses And Series Parameters
If a transformer is operating in .8 PF lag & at efficiency of .9
if now P is .8 lead the efficiency will become
0.9 Only Because Efficiency curve is Single valued cure
Dielectric strength of air is?
30 kv/cm peak or 21.1 kv/cm rms
The voltage of a generator and an infinite bus are given
0.92, 10 deg & 1.0, 0 deg respectively the generator acts as a
Synchronous generator
A wave will not experience any reflection when impedance of line is equal to
Surge impedance
400 ohms for over head lines
40 to 50 ohms for cables
Power transmitted is related to system voltage as
P=EV/Xs Sinδ
Surge wave is attended by
Resistor
In galvanometer damping is provided by
Mechanical and electromagnetic
Megger is used for
Measurement of Very high resistance like insulation resistance of the cable etc
Its working principle is based on moving coil
AC is applied against a moving coil meter it will read
Zero if frequency is high
Oscillate around zero if frequency is low
Rectifier type instrument measures what value
RMS
Advantage of electrostatic instrument is
More accurate
Loading effect is low
Fast response etc.
Creeping occurs because
Over compensation due to frictional forces
Over voltage across pressure coil
Why 2 holes are drilled oppositely in disc of energy meter
To eliminate the creeping
Energy meter is_____ type equipment
Integrating / recording
Inductance is measured by which bridge
Maxwell’s, Anderson, Hay’s, Owen’s bridge
Which type of motor is used in refrigerator?
Capacitor Start and run Single phase induction motor
Corona’s advantage
To increases the virtual diameter of conductor
To protect the conductor from Switching over voltages
Reflection coefficient of current in open ended line is
-1
Reflection coefficient of voltage in open ended line is
1
Reflection coefficient of current in short circuit line is
1
Reflection coefficient of voltage in short circuit line is
-1
Calculation of making current when MVA & KV was given.
Making current=2.5*breaking current
Breaking current=MVA/KV
he o/p voltage e1 & e2 of 2 full-bridge inverters added using o/p transformer. In order to eliminate 5th harmonic from o/p voltage, the phase angle between e1&e2 will be-
36◦
A single phase fully controlled line commutated ac-dc converter operates as an inverter when-
α > 90◦
Why rotor of SCIM is skewed?
To eliminate the slot harmonics in the rotor
Magnetostriction is occurs in
AC circuits’ only
Interlopes are connected for?
To eliminate the Armature reaction
Identify type by pu value Xd”=0.3, Xd’=0.3, X0=0.6?
Transmission line
What to do for converting sine wave to triangular wave?
Integrating
Wave shape of armature mmf?
Triangular wave
Emf in a conductor is directly proportional to?
E α ΦZNP
What’s the order of Jacobin matrix for 20 no. of bus bar?
=2n-2
N=no of buses
=38
How many watt meters required to measure 3phase 4 wire system?
3
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