BSNL JTO (Junior Telecom Officer)- 2010 · BSNL JTO (Junior Telecom Officer)- 2010 Q.1 A house...

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BSNL JTO (Junior Telecom Officer)- 2010 Q.1 A house served by a 220V supply light, is protected by a 9-Ampere fuse. The maximum number of 60 W bulbs in parallel that can be turned on is (a) 11 (b) 33 (c) 22 (d) 44 Q.2 An n-channel JFET has IDSS = 1 μA & VP =–5V. The maximum transconductance is (a) gm = 0.4 milli mho (b) gm = 0.04milli mho (c) gm = 0.04 mho (d) gm = 0.4 millimilli mho Q.3 The base to base resistance of a UJT is 6 K Ohm when the emitter current is zero. If RB1 = 3.6 K Ohm, the intrinsic stand off ratio is (a) n = 0.66 (b) n = 0.6 (c) n = 6.0 (d) n = 3.6 Q.4 A capacitor of 1μF initially charged to 10 V is connected across an ideal inductor of 0.1 mH. The maximum current in the circuit is (a) 0.5 A (b) 1 A (c) 1.5 A (d) 2 A Q.5 Silicon has a preference in IC technology because (a) it is an indirect semiconductor (b) it is a covalent semiconductor (c) it is an elemental semiconductor (d) of the availability of nature oxide SiO Q.6 Three equal resistance of magnitude 5 Ohm each are connected in delta. The resistance between any two pair of terminals of the delta will be (a) 5 Ohm (b) 5/3 Ohm (c) 10/3 Ohm (d) 3/5 Ohm Q.7 The R.M.S. value of a half wave rectified sinusoidal alternating current with

Transcript of BSNL JTO (Junior Telecom Officer)- 2010 · BSNL JTO (Junior Telecom Officer)- 2010 Q.1 A house...

Page 1: BSNL JTO (Junior Telecom Officer)- 2010 · BSNL JTO (Junior Telecom Officer)- 2010 Q.1 A house served by a 220V supply light, is protected by a 9-Ampere fuse. The maximum number of

BSNL JTO (Junior Telecom Officer)- 2010

Q.1 A house served by a 220V supply light, is protected by a 9-Ampere fuse.

The maximum number of 60 W bulbs in parallel that can be turned on is

(a) 11 (b) 33

(c) 22 (d) 44

Q.2 An n-channel JFET has IDSS = 1 μA & VP =–5V. The maximum

transconductance is

(a) gm = 0.4 milli mho (b) gm = 0.04milli mho

(c) gm = 0.04 mho (d) gm = 0.4 millimilli mho

Q.3 The base to base resistance of a UJT is 6 K Ohm when the emitter current is

zero. If RB1 = 3.6 K Ohm, the intrinsic stand off ratio is

(a) n = 0.66 (b) n = 0.6

(c) n = 6.0 (d) n = 3.6

Q.4 A capacitor of 1μF initially charged to 10 V is connected across an ideal

inductor of 0.1 mH. The maximum current in the circuit is

(a) 0.5 A (b) 1 A

(c) 1.5 A (d) 2 A

Q.5 Silicon has a preference in IC technology because

(a) it is an indirect semiconductor

(b) it is a covalent semiconductor

(c) it is an elemental semiconductor

(d) of the availability of nature oxide SiO

Q.6 Three equal resistance of magnitude 5 Ohm each are connected in delta.

The resistance between any two pair of terminals of the delta will be

(a) 5 Ohm (b) 5/3 Ohm

(c) 10/3 Ohm (d) 3/5 Ohm

Q.7 The R.M.S. value of a half wave rectified sinusoidal alternating current with

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peak value Im is

(a) Im/1 (b) mI / 2

(c) mI /2 (d) mI 3

Q.8 For a series resonant circuit, at the half power points,which of the following

is true?

(a) Current is half of the current at resonance.

(b) Resistance is equal to the reactance.

(c) The impedance is half the impedance at the resonance.

(d) None of the above

Q.9 The lossless line of characterstics impedance 300 Ohm is terminated in a

pure resistance of 200 Ohm. The value of the standing wave ratio is

(a) 1.5 (b) 0.67

(c) 1.0 (d) 1.25

Q.10 The transient current in lossless L-C circuit when excited from an AC

source is, sine wave

(a) Critically damped (b) Underdamped

(c) Overdamped (d) Undamped

Q.11 The values of L and C for a low pass filter with cut off frequency of 2.5 KHz

and operating with a terminated load resistance of 450 Ohm are given by

(a) 57.3 mH; 0.283 μF (b) 28.66 μH; 0.14 μF

(c) 114.64 mH; 0.566 mF (d) 50.23 mH; 0.632 mF

Q.12 The driving point impedance with poles at ? = 0(zero) and ? = 8 (infinity)

must have the

(a) s term in the denominator and an excess term in the numerator

(b) s term in the numerator and an excess term in the denominator

(c) s term in the numerator and equal number of terms in the

numerator and denominator

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(d) s term in the denominator and equal number of terms in the

numerator and denominator

Q.13 A transmission line is terminated at its characterstic impedance. The

reflection coefficent is

(a) 1 (b) –1

(c) 0 (d) 8

Q.14 In the circuit shown below, the current through the 3/11O resistance

between terminals A & B is

(a) 4 Amps (b) 1 Amp

(c) 2 Amps (d) 5 Amps

Q.15 In a series RLC circuit operating below the resonant frequency the current

(a) I leads Vs (b) I lags Vs

(c) I is in Phase with Vs (d) None of these

Q.16 An antenna has maximum radiation intensity Umax = 10 Watt/Sr and

average radiation intensity Uavg = 4.5 Watt/Sr. If the efficiency of the antenna

is given as ?r = 95%, the input power of the antenna is

(a) 2.222 Watt (b) 12.11 Watt

(c) 55.55 Watt (d) 59.52 Watt

Q.17 In an airport, a receiving, antenna has a maximum dimension of 3 metres

and operates at 100 MHz. An aircraft approaching the airport is 1/2 Km away

from the antenna . The aircraft is in the region of the antenna.

(a) far-field (b) near-field

(c) close-field (d) Out of reach

Q.18 A lossless transmission line with characterstic impedance 500 Ohms is

excited by a signal of voltage 10?0° volts at 1.2 MHz. If the line is terminated

by ZL at a distance 1 Km, the input impedance s of the line for ZL = 8 (infinity)

and ZL = 0 (zero) in Ohm, respectively are

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(a) +j8, 0 (b) –j8, 0

(c) 0, – j8 (d) 0, +j8

Q.19 If the electric field of a plane wave is represented by E = 10 yˆ cos (109

t+30z) volt/m, assuming e is the dielectric constant, the corresponding

magnetic field H is

(a) – ˆy e 109/3 cos (109 t + 30z) Amp/m

(b) – ˆx e109/3 cos(109t + 30z) Amp/m

(c) – ˆz e 109/3 cos (109t + 30 z) Amp/m

(d) + ˆx e 109/3 cos (109t+30z) Amp/m

Q.20 A 50 Ohm lossless line connects a signal of 200 KHz to a load of 200 Ohm.

If the load power in 100 mW, the value for voltage minimum Vmin is

(a) ( 20)/4 (b) ( 10)/ 4

(c) ( 20)/ 2 (d) ( 10)/ 2

Q.21 Choose the correct statement

(a) Digital multimeters are built using current measuring elements, while analog

multimeters are built using voltage measuring units

(b) Digital multimeters are built using voltage measuring units, while analog multimeters

are built using current measuring units

(c) Both digital and analog multimeters are built using voltage measuring units

(d) Both digital and analog multimeters are built using current measuring units

Q.22 An analog voltmeter has a sensitivity of 10kO/volt. The galvanometer

used in constructing the instrument will produce a full scale deflection when

the current passed through it is

(a) 10 mA (b) 20 mA

(c) 50 mA (d) 100 μA

Q.23 The input versus output characteristics of a digital-to-analog converter is

given in the table below: The converter is exhibiting

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(a) offset error (b) statistical error

(c) linearity error (d) hysteresis error

Q.24 An optical fiber cable laid underground has developed a discontinuity at a

distance d from the source end. The fault can be located using the instrument

(a) Optical spectrum Analyzer (OSA)

(b) Optical Time Domain Reflectometer (OTDR)

(c) Optical Power Meter (OPM)

(d) Laser Diffractometer (LD)

Q.25 Two sinusoidal signals of the same frequency are displayed on a dualtrace

oscilloscope. One complete cycle of each signal covers 6 cm of the

horizontal scale and the starting point of the horizontal scale and the starting

point of the two signals are separated by 0.5 cm. The phase difference between

the two signals in degrees is

(a) 30 (b) 45

(c) 60 (d) 90

Q.26 Transient signals can be observed using

(a) storage oscillocope (b) sampling oscilloscope

(c) wave analyzer (d) spectrum analayzer

Q.27 The trace on an oscilloscope continually moves to the right of the screen

when

(a) the sweep is triggered.

(b) the sweep period is larger than the signal period.

(c) the sweep period is smaller than the signal period.

(d) there is no weep.

Q.28 In a dual trace oscilloscope, the display appears segmented when

(a) low frequency signals are observed in Alternate mode

(b) low frequency signals are observed in Chop mode

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(c) high frequency signals are observed in Alternate mode

(d) high frequency signals are observed in Chop mode

Q.29 To distinguish between signals having very close values, we need an

instrument with

(a) high accuracy (b) high resolution

(c) high sensitivity (d) high linearity

Q.30 Match List-I (Instruments) with List-II (Measurement in which the

instrument is used) and select the correct answer using the codes

given below the lists:

List-I List-II

A. Lock-in amplifier 1. Patient monitoring

B. Sampling oscillocope 2. Overcoming ground loop problem

C. Isolation amplifier 3. Phase difference between two signals

D. Strip-chart recorder 4. Signal recovery from noise 5. Observing very high

frequency signals

Codes:

A B C D

(a) 1 3 5 4

(b) 2 1 3 4

(c) 4 5 2 1

(d) 3 4 1 2

Q. 31 A power diode has lightly doped n type substrate sandwiched between

heavily doped p and n regions

(a) to increase reverse breakdown voltage

(b) to reduce ohmic loss under forward bias

(c) to decrease switching time of the power diode

(d) to improve transient behaviour of the diode

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Q.32 An ideal thyristor is driving an R-L load of impedance Z. Input AC voltage

is Vs = Vm sin ?mt. If thyristor is fired at an input phase angle of 90°. What will

be the output voltage and output current across R-L load at the instant of

firing?

(a) Output voltage is Vm and output current is Vm/Z

(b) Output voltage and output current are both zero

(c) Output voltage is zero and output current is delayed by an angle 90°

(d) Output voltage is Vm and output current is zero

Q.33 In a regenerative braking, which of the following is generally true?

(a) Back e.m.f. in the motor exceeds the applied voltage

(b) Back e.m.f. is less than the applied voltage

(c) Kinetic energy of the motor is dissipated in a resistance

(d) Kinetic energy of the motor is dissipated through free wheeling

diode across the motor

Q.34 A step-down chopper, fed from a 120 volt DC source, operates a DC motor

whose armature e.m.f. and armature resistance are 100 volt and 0.5O

respectively. With the magnitude control ratio 0.6, the quadrant of operation

DC motor is

(a) First (b) Second

(c) Third (d) Fourth

Q.35 For IGBT, which of the following statement is true?

(a) Switching speed of IGBT is more than bipolar transistor

(b) IGBT is a current-controlled device

(c) On-state collector-emitter voltage is less than that of bipolar junction transistor

(d) It combines voltage control features of MOSFET gate and high power capability of

bipolar transistor

Q.36 The semiconductor used for LEDs emitting in the visible range is

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(a) GaAs (b) GaAlAs

(c) GalnAs (d) GaAsP

Q.37 The polar bonds existing in III-V compound semicondutor, may be

considered as equivalent to

(a) 1 ionic bond and 3 covalent bonds

(b) 1 ionic bond and 4 covalent bonds

(c) 2 ionic bonds and 2 covalent bonds

(d) 2 ionic bonds and 4 covalent bonds

Q.38 Which of the following pairs of crystal structure possesses the same

atomic packing density?

(a) simple cubic & body centred cubic

(b) body centred cubic & face centred cubic

(c) face centered cubic & hexagonal close packed

(d) body centred cubic & hexagonal close packed

Q.39 The colour bands on a carbon composition resistor occur in the sequence:

yellow, violet, yellow and silver. Its resistance is

(a) 470 KO ± 47 KO (b) 470 KO ± 23.5 %

(c) 47 KO ± 10 % (d) 47 KO ± 5 %

Q.40 The real & imaginary dielectric constants er’ and er” of 3 insulators at 1

KHz and 50° C are listed below:

Material er’ er”

Polycarbonate 2.47 0.003

PET 2.58 0.003

PEEK 2.24 0.003

At a given voltage, the lower power dissipation per unit capacitance at 1 KHz

can be obtained from

(a) Polycarbonate

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(b) PET

(c) PEEK

(d) Insufficient information to answer

Q.41 A battery of 40 V and three capacitors of 1000 μF, 500 μF and 100 μF are

all connected in (I) parallel and (II) series. The ratio of total charge stored in

case I to that in case II is approximately

(a) 3 : 64 (b) 64 : 3

(c) 160 : 3 (d) 104 : 5

Q.42 The magnetic flux f ( in Weber) linked with a coil at an instant of time t(in

second) is given by f(t) = 2t2 – 20t + 40. The induced e.m.f. in the coil at the

instant t =2 second is

(a) 22 V (b) 20 V

(c) 12 V (d) 10 V

Q.43 The speed of an audio cassette tape in a cassette player is 5cm/ sec. If

the maximum frequency that needs to be recorded is 20 KHz, the minimum

spatial wavelength on the tape is

(a) 40 μm (b) 25 μm

(c) 4 μm (d) 2.5 μm

Q.44 In a power transformer, the fundamental frequency of the hum arising

due to magnetostriction is

(a) equal to the line frequecy

(b) double the line frequency

(c) 4 times the line frequency

(d) not related to the line frequecny

Q.45 At a particular temperature and current density, the critical magnetic field

for a Type I superconductor is Bc and that for a type II superconductor ranges

from Bc1 to Bc2 keeping other parameters unloaded. both superconductors are

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now subjected to a magnetic field B that satisfies the conditions B>Bc and

Bc1 < q =”4q9,” x =”d3″ q =”–4q9,” x =”dQ4=”" q =”–4q9,” x =”d3″ q =”–

4q9,” x =”d4″ gap =” 1.1″ charge =” 1.6″ a =” 0.99,” ib =” lB” icbo =” 200″ ic

=” 2.5″ ic =” 1.5mA” ic =” 3.5″ ic =” 4.5″ 1 =” A.Qn” 1 =” A.Qn+” 1 =” A.Qn” 1

=” A.Qn” k =” 0,” n =” (no.” mp =” 1.15.” x =” P.Q” y=”P.R” i0 =” X,” i1=” 0,”

i2 =” X,” i3 =” X” i0 =” 0,” i1=”1,” i2 =” Y,” i3 =” X” i0 =” X,” i1 =” 1,” i2 =”

0,” i3 =” X” i0 =” X,” i1 =” 0,” i2 =” X,” i3 =” Z” k =” 0.” dt =” Ax(t)” a =”–2″ b

=”10″ a =”0″ b =”0″ fc =” 0.16″ d =” 0.5456″ n =” 31.6″

(a) > 100 (b) > 500

(c) > 1000 (d) > 20000

Q.67 In an IF amplifier, the IF transformer is provided with tapping to

(a) increase the voltage gain

(b) increase the bandwidth of the resonance circuit

(c) increse the impedance offered by the resonance circuit to the following cascaded

amplifier

(d) increase the quality factor of the resonance circuit

Q.68 Consider the wave form V(t) = (1+m cos?mt) cos?ct. Show that, if the

demodulated wave is to follow the envelope of V(t), it is required that at any

time t0

(a) RC <=?m(msin?mt0 ) / (1+mcos?m t0)

(b) (I/RC) >= ?m(msin?mt0 ) / (1+mcos?m t0 )

(c) 1/RC <= 1/(m?m)

(d) RC is very large

Q.69 QPSK system is superior to BPSK system because

(a) its bandwidth is higher than that of BPSK System

(b) interchannel interference in QPSK system is less then that in BPSK system

(c) bandwidth of QPSK system is half of the bandwidth of BPSK system

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(d) in QPSK system inter-symbol interference is inproved

Q.70 A radio receiver is placed at one corner of a table and again placed at

some other corner of the same table. Loudspeaker output is changed because

(a) image interference is reduced

(b) adjacent channel interference is increased

(c) of fading

(d) line of sight propagation is not utilized

Q.71 In time-division multiple access system, a traffic system on the receiver

side must receive the traffic burst addressed to it. For this

(a) transmitting frame acquisition is required

(b) proper synchronization of the timing of transmit frame is required

(c) frame efficiency should be higher

(d) synchronization is necessary to overcome the perturbations of the satellite

Q.72 Earth coverage dish antenna is used in satellite system. It is characterized

by the fact that

(a) It is a narrow beam antenna

(b) It is Parabolic antenna

(c) it is sharply focused within a small area of the surface of the earth

(d) it is a wide angle antenna which covers a large area of the surface of the earth

Q.73 In a Klystron amplifier, the RF voltage produces

(a) amplitude modulation (b) frequecny modulation

(c) phase modulation (d) velocity modulation

Q.74 For the proper operation of MASER at a frequency of 10 GHz, the material

used is

(a) Al2 O3 with slight doping of chromium

(b) Ti O2 with slight doping of iron

(c) Ti O2 with slight doping of chromium

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(d) Al2 O3 with slight doping of iron

Q.75 A rectangular waveguide is 4.2 cm by 1.85 cm. The cut-off frequency of

the dominant mode through this waveguide is

(a) 3.57 GHz (b) 3.75 GHz

(c) 3.70 MHz (d) 3.57 MHz

Q.76 For an antenna to be frequency-independent, it should expand or contract

in proportion to the

(a) gain (b) directivity

(c) wavelength (d) impedance

Q.77 Suppose that data items, numbered 1, 2, 3, 4, 5 and 6 come in the input

stream in this order. By using a queue, which of the following rearrangement

can be obtained in the output order ?

(a) 1 2 6 4 5 3 (b) 2 4 3 6 5 1

(c) 4 2 1 3 5 6 (d) 1 2 3 4 5 6

Q.78 We are told that the integers between 1 and 1000 are arranged in a binary

search trace with ‘<‘ as the ordering relation. Below are four lists of vertices

encountered as we search for the number 363. Which list cannot be produced

by this search through a binary search tree?

(a) 924, 220, 911, 244, 898, 248, 363

(b) 2, 252, 401, 398, 330, 344, 397, 363

(c) 925, 202, 911, 240, 912, 245, 363

(d) 2, 399, 387, 219, 266, 382, 381, 278, 363

Q.79 The number of 1’s in the binary representation of 13* 163 +11*16 + 2 is

(a) 8 (b) 7

(c) 9 (d) 12

Q.80 A disk has 500 bytes/sector,100 sectors / track, 20 heads and 1000

cylinders. Total capacity of disk is

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(a) 1 GB (b) 100 MB

(c) 10 MB (d) 10 GB

Q.81 Suppose that the same clock signal is used to increment the microprogram

counter and to load the control register. Which of the following asseration(s)

is/are true?

1. Microinstruction execution time is at least two clock periods.

2. Microinstruction exceution time can be overlapped with fetching the next

microinstruction.

3. Unconditional branch microinstructions must necessarily take longer than

other types.

(a) 1 only (b) 2 only

(c) 1 and 3 (d) 2 and 3

Q.82 Some system architects do not find RISC instruction repertoire to be costeffective

because it

(a) result in large increase in programme size

(b) result in complex structure of microcode

(c) has been observed that an average compiler does not employ more than a limited

subset of available instructions

(d) results in complex decoding of opcode filed resulting in longer execution time

Q.83 A stake machine pushes operands on a stack and evaluates binary

operators by a pcs (i.e pop/compute/store) where the top two operands are

popped computation is performed and the result is pushed onto stack.

Evaluation of an expression (x* y) + (u* ?) by Reverse Polish notation in a

stack machine needs

(a) 4 push and 3 pcs instructions

(b) 6 push and 1 pcs instructions

(c) 4 push and 1 pcs instructions

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(d) 5 push and 2 pcs instructions

Q.84 A dot matrix printer takes 3 msec to point a character, and 1 msec for a

space between two consecutive characters. If it prints 100 characters per line,

its printing speed specifications in characters per second (cps) and time to

print a line of characters are respectively

(a) 100 cps and 400 msec

(b) 2500 cps and 0.04 sec

(c) 250 cps and 40 msec

(d) 250 cps and 0.4 sec

Q.85 Consider the following program segment with 8085 microprocessor

LXI H 3600H

MOV A, M

HLT

The MOV instruction involves

(a) indirect addressing

(b) immediate addressing

(c) implicit addressing

(d) direct addressing

Q.86 To establish a communication between 8085 microprocessor and 8255

Programmable Peripheral Interface chip. the status of the chip select input

would be

(a) TRISTATE (b) HIGH

(b) LOW (d) DON’T CARE

Q.87 Which flag does not change by the execution of the instruction DCR B in

8085 microprocessor ?

(a) Parity (b) Carry

(c) Zero (d) Sign

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Q.88 Let the content of the memory location 3501H be 72H. Now consider the

following program with 8085 microprocessor

LDA 3501H

CMA

STA 3502H

HLT

The content of the memory location 3502H after execution of

programme will be

(a) 27H (b) D8H

(c) 8DH (d) 72H

Q.89 Given the program segment below, how many times will the instruction

LP: JNZ REP be executed?

MVI H, 02H

MVI L, 05H

REP : DCR L

LP : JNZ REP

: DCR H

: JNZ REP

……………….

(a) 10 (b) 260

(c) 510 (d) 7

Q.90 What addressing mode is used in the instruction RET?

(a) Direct (b) Immediate

(c) Implicit (d) Register-indirect

Q.91 A one-byte instruction is executed in the 8085 microprocessor by the

following steps:

((SP) –1) ? (PCH)

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((SP) –2) ? (PCL)

((SP) ? ((SP)-2)

(PC) ? 0008H

The corresponding instruction is

(a) JMP 0008H (b) PUSH PSW

(c) CALL 0008 H (d) RST 1

Q.92 The zero flag of 8085 microprocessor is to be set keeping the content of

the accumulator unchanged. Which instruction is to be used?

(a) MOV A,A (b) ANI 00H

(c) XRA A (d) CMP A

Q.93 In class – A power amplifier, the collector dissipation is maximum when

(a) no signal is present

(b) signal swing is maximum

(c) signal swing is (1/1.414) of its maximum

(d) none of the above

Q.94 If cut-in voltage and forward resistance of each diode (in the adjoining

figure) are 0.7 V and 1 ohm respectively, the current through the 48 ohm

resistor is

8 V

+ 48 O

(a) 132 mA (b) 160 mA

(c) 0 mA (a) (1/6) A

Q.95 The lower cut-off frequency of the transistor stage in the adjoining figure

is

Vcc

3 K

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10 μF

V0

2 K

(a) 7.95 Hz (b) 13.25 Hz

(c) 5.30 Hz (d) 3.18 Hz

Q.96 In the adjoining current mirror circuit if Q1 and Q2 are identical and base

currents are not neglected, then which of the following is true ?

I1 I2

Q1 Q2

(a) I2 = I1 (b) I2 = ßl1

(c) I2 = [(ß/(ß +2)]I1 (d) I2 = [(ß + 2)/ß]I1

Q.97 If rectangular input is applied to the adjoining circuit, it produces

R

C

I/P O/P –

+

(a) square output (b) spike output

(c) sinusoidal output (d) none of the above

Q.98 In an oscillator, if amplifier gain (A) without feedback is (1 + RF/ R1) and

gain (ß) of the feedback network is 1/{3 + j(?Rc–1/?Rc)}, then which of the

following is true ?

(a) RF = 2R1 (b) RF = R1

(a) |ß| = 3 (b) |ß| = 1/3

1. The main scale of a vernier calliper is ruled in

1 mm units. The vernier scale is 49 mm long

and divided in 50 units. The resolution of the

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vernier calliper is

a. 0.002 mm

b. 0.005 mm

c. 0.01 mm

d. 0.02 mm

2. A frequency counter with a gating time of 50

ms counts 1254 cycles of an input square

wave. The frequency of the input wave is

a. 39.87 Hz

b. 62.70 Hz

c. 1.254 kHz

d. 25.08 kHz

3. A data acquisition system with the input range

of ± 5.0 V has a 12-bit ADC in it. The

resolution of the system is approximately

a. 0.24 mV

b. 0.48 mV

c. 1.22 mV

d. 2.44 mV

4. Wattmeters are based on the principle of

a. permanent magnet moving coil meter

b. electrodynamic meter

c. electrostatic meter

d. moving iron meter

5. The resolution of a Gray-coded optical shaft

encoder with 10-bit output is approximately

a. 0.098°

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b. 0.176°

c. 0.225°

d. 0.352°

3 3 2

2 3

e s Y s

s s

is

7. The undamped natural frequency in rad/s and

the damping ratio of the system with the

2

2

64

12 100

G s s

s s

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are,

respectively,

a. 10 and 1.2

b. 10 and 0.6

c. 8 and 1.2

d. 8 and 0.75

8. The gain at the breakaway point of the root

locus along the real axis of a unity feedback

system with the transfer function

G s K

s s

is

a. K = 0

b. K = 0.5

c. K = 1

d. K = 1.25

9. Gain margin of the unity feedback system with

100

1

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G s

s

is

a. 35.35

b. 12.5

c. 0.08

d. 0.03

10. The discrete time system with the transfer

1

0.4 0.25 0.1

G z

z z z

is

a. stable

b. unstable

c. marginally stable

d. sustained oscillatory

a. C2 N–1 m–2

b. C2 N m2

c. C–2 N m2

d. C–2 N m–1

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12. A positively charged object is placed in the

centre of a room with a uniform magnetic

field. If the magnetic field is pointing east, the

object will

a. move east

b. move north

c. move south

d. remain stationary

13. The input impedance of a quarter-wave long

short-circuited lossless transmission line is

a. purely reactive

b. purely resistive

c. infinite

d. dependent on the characteristic impedance

of the line

14. For a plane wave propagating in the free

space,

Set-D ELECTRICAL ENGINEERING

BSNL JTO(EE) 2009

SECTION-I

QUESTION NUMBER 1-20

CARRY 1 MARK EACH

a. the electric and magnetic fields are in

parallel to the direction of propagation

there is no field in the direction of

propagation

b. the electric and magnetic fields are out of

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phase

c. the magnetic field amplitude is inversely

proportional to the electric field amplitude

15. Which of the following materials has the

largest energy gap between the conduction

band and the valence band?

a. Gold

b. Silicon

c. Doped germanium

d. Porcelain

16. The area of hysteresis loop in a ferromagnetic

material is a measure of

a. loss of energy

b. loss of magnetic domain

c. loss of magnetic dipole

d. loss of eddy currents

17. If a tetra-valent impurity is added to a pure

silicon crystal at room temperature, it becomes

a. a p-type semiconductor

b. an n-type semiconductor

c. an npn-type semiconductor.

d. an insulator

18. The circuit shown in Fig. I.18 has the

following source values:

VA = 600 t u(t+1) V, VB = 600(t+1) u(t) V and

IC = 6 (t—1) u(t—1) A, where u(.) denotes the

unit step function. For this circuit, the current i

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at t = –0.5s will be

a. -9 A

b. -6 A

c. -1 A

d. 0 A

19. Assuming the transformer in Fig. I.19 ideal,

the effective value of the load seen by the

source is

20. If an electrical transformer and a mechanical

gear system are considered analogous to each

other, the equivalent quantity of the

transformer primary voltage in the gear system

will be

a. angular speed

b. displacement

c. torque

d. moment of inertia

21. If a unit ramp input v(t) is applied to the

circuit shown in Fig. I.21, then the steady state

value of the output will be

a. 0.002

b. 5

c. 500

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d. 2000

22. An analog dc ammeter of full scale current of

1 mA is obtained by connecting a shunt

galvanometer having a full scale current of

for obtaining an ammeter of full scale current

of 10 mA using the same galvanometer is

23. An average responding analog ac voltmeter

using half wave rectifier to read RMS value of

the input sinusoidal voltage. If the meter reads

24 V for a square wave input with zero mean,

the actual RMS value of the input is

a. 24 2 V

b. 24

2

V

c. 48 2 V

d. 24

2

V

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24. A resistance is measured by the voltmeterammeter

method. The voltmeter reading is 25

V on the 100 V scale and the ammeter reading

is 250 mA on the 500 mA scale. Both meters

are accurate within ±1 per cent of full-scale

reading. The maximum possible error, in

percent of measured value of the resistor is

QUESTION NUMBER 21-50

CARRY 2 MARKS EACH

www.estudentzone.com

FaaDoOEngineers.com

a. ± 2%

b. ± 2.5%

c. ±4%

d. ±6%

25. An energy meter makes 200 revolutions of

disc per unit of energy. The meter is tested by

connecting to a load of 20 A at pf 0.8 lagging

in 250 V mains for one hour. If the observed

number of revolutions is 760, the percentage

error in the meter is

a. 0.5% fast

b. 2.5% fast

c. 5% slow

d. 25% slow

26. The ac bridge given in Fig. I.26 is balanced at

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inductor L is

a. 1 H

b. 0.1 H

c. 0.5 mH

d. 0.2 mH

resistors in other three arms. The bridge

supply is 5.4 V with the RTD connected to

zero potential and the bridge is balanced at

0°C. At room temperature the bridge

unbalanced output voltage is 0.2 V with the

RTD side of the output being positive. The

room temperature is

a. 6.4°C

b. 15°C

c. 25°C

d. 40°C

28. The volumetric flow rate (Q) for a turbine

flowmeter with 8 blades in the rotor is given

–5

ngular velocity in

rad/s. If a proximity device used to pick-up

presence of rotor blades gives output of 48

pulses/s, the flow rate is

–5 m3/s

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–5 m3/s

–4 m3/s

–4 m3/s

29. Which of the following conditions ensures that

exactly two roots of s3 + as2 + s + c = 0 lie in

the right half of the s-plane?

a. a > 0, c > 0 and a > c

b. a >0, c > 0 and a < c

c. a > 0 and c < 0

d. a < 0 and c = a

30. The loop transfer function of a unity feedback

1

1 4

s s K

G s

s s

. For

a. s = –1 and s = –4

b. s = –1 + j and s = –1 – j

c. s = 1 and s = –

d. s = –3+ 6 and s = –3– 6

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31. The approximate transfer function of a system

with the following frequency response is

Gain in dB -20 -20.5 -26 -60

Phase in

Degree 0 0 -90 -180

a.

0.9

0.9

0.9

0.9

32. The diagonal form of the state space

representation of a SISO system with the

transfer function

2

3 2

3 6 2

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3 2

Y s s s

U s s s s

can be

expressed as

a.

0 0 0 1

0 1 0 1

0 0 2 1

1 1 1

x x u

y x

b.

0 0 0 1

0 1 0 1

0 0 2 1

3 6 2

x x u

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y x

c.

0 0 0 1

0 1 0 1

0 0 2 1

0 1 2

x x u

y x

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d.

0 0 0 1

0 1 0 1

0 0 2 1

2 6 3

x x u

y x

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33. A feed forward controller of the form

K s a

G s

s b

is designed for a plant with

1

3

G s

s s

such that

the undamped natural frequency and the

damping ratio of the closed loop second order

system are 2 rad/s and 0.5, respectively. When

the steady state error to a unit step input is

zero, then the controller parameters are

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a. K=4, a=3, b=2

b. K=1, a=3, b=2

c. K=4, a=2, b=3

d. K=1, a=2, b=3

34. The transfer function of the system with the

state space representation

; 11

0 1 1

x u y x u

is

1

1

c.

2

1

s

s

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d.

2

1 1

s

s s

35. The system with the state space representation

as given in Q.34 is

a. controllable

b. observable

c. marginally controllable

d. not observable

s

The state feedback gain controller k that places

the pole of the regulatory control system at s =

—1 is given by

a. k = 0

b. k = 0.5

c. k = 1

d. k = 2

37. The state space representation of the system

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shown in Fig. I.37 can have the state and

output equation constants

a.

0 0 0

A 1 ,B 1 ,C 1

R R C

b.

0 0 0

A 1 ,B 1 ,C 1

C R C

c.

0 0 0 0

A 1 ,B 1 ,C 1

R C R C

d.

0 0 0 0

A 1 ,B 1 ,C 1

R C R C

38. A unit step sequence is applied as the input to

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a system with the closed loop transfer function

2

2

4 8 1

12 5 2

T z z z

z z

. The steady state error of

the system is

a. 1

15

b. 3

15

c. 4

15

d. 11

15

39. Which of the following field equations

indicates that isolated magnetic charges do not

exist?

a. 0

v

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b. 0

4 2

B I dl r

R

40. A transmission line of characteristics

transmission line will be

a. 1.2 : 1

b. 1.5 : 1

c. 2 : 1

d. 5 : 1

a. F

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b. F

must be perpendicular to B

but not to

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FaaDoOEngineers.com

d. F

must be perpendicular to the plane

.

42. A 1 m long wire with a radius of

10 3 m

carries a current of 20 A. If power dissipation

along the wire is 4 W/m, the conductivity of

–1 m–1) is

a. 4×108

b. 108

c. 107

d. 5×108

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43. A parallel plate capacitor is made to store 5 ×

10–6 C. The separation distance between the

plates is 0.3 mm and area of each of the plates

is 0.02 m2. If vacuum is used as dielectric

between the plates, the voltage rating of

capacitor is

a. 0.118 mV

b. 118V

c. 8.475 kV

d. 8.475 MV

(Given that the permittivity of free space is

8.85 x 10–12 F/m)

44. The value of the load current IL in Fig. I.44 is

a. 50/31 A

b. 5/11 A

c. 5/31 A

d. 0 A

45. The current (iC) through the capacitor in Fig.

I.45 is

a. 0 A

b. 0.625 sin(200t) A

c. 0.88 sin(200t — 45°) A

d. 1.25 sin(200t) A

46. The capacitor in Fig. I.46 is initially

discharged. At t = 0 s, the switch is closed. At

t = 100 ms the current (IC) through the

capacitor is

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a. 0 mA

b. 4

5

mA

e

c. 12

5

mA

e

d. 4 mA

e

47. The switch in Fig. I.47 is closed at t = 0 s. At

steady state, the current (IL) through the

inductor is

a. 0 A

b. 2 A

c. 30/7 A

d. 8 A

48. In the circuit shown in Fig. I.48, the Norton

equivalent current IN and resistance RN

between the points a and b are

a. IN = —

b. IN = —

c. IN = —

d. IN = —

49. The nodal voltage V1 in Fig. 1.49 is

a. –13.5 V

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b. – 6.75 V

c. – 4.5 V

d. 0 V

50. A balanced 440 V, 3 phase supply is driving a

parallel combination of star and delta loads. If

phase, the supply current per phase is

a. 44

3

A

b. 44 3A

c. 176

3

A

d. 176 3 A

1. An arithmetic operation in the 8085

microprocessor sets the sign and parity flags.

The contents of the accumulator after the

execution of the operation can be

a. 1011 0100

b. 0010 1101

c. 1010 1101

d. 0110 0111

2. An instruction of the 8085 microprocessor that

requires both memory read and memory write

machine cycles is

a. MVI M, 8F

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b. LHLD 8088

c. RST 1

d. ADD M

3. The duration of one T-state in the 8085

microprocessor that uses a crystal of 5.00

MHz is

4. In a vacuum diode, the discrete nature of

electron flow causes

a. thermal noise

b. white noise

c. filtered white noise

d. shot noise

5. The rate at which information can be passed

through a telecommunication channel depends

on the

a. JM carrier frequency

b. carrier bandwidth

c. transmission loss

d. transmission power

6. In a commercial TV broadcasting system, the

receiver filter structure for the video signal and

the frequency gap between audio and video

carriers are, respectively,

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a. VSB,4.5 MHz

b. LPF,4 MHz

c. HPF, 3 MHz

d. BPF, 2 MHz

7. The SCR turn-off time increases with

a. lower junction temperature

b. lower operating frequencies

c. lower positive gate biases

d. lower peak reverse current

8. The freewheeling diode in a single phase

controlled rectifier with inductive load results

in

a. a small ripple voltage and reduction of

reactive power

b. a large ripple voltage and reduction of

reactive power

c. a decreased range of firing angle

d. a negative average load voltage

9. The chopper circuit shown in Fig. 11.9

operates the motor in quadrants

a. I and II

b. II and III

c. I and III

d. I and IV

10. A 280 V, 10 hp, 4 pole, 60 Hz star connected

induction motor has full load slip of 5%. If

rotor is blocked, its electrical frequency is

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a. 0 Hz

b. 3 Hz

c. 50 Hz

d. 60 Hz

11. An ideal transformer core should have

a. high reluctance

b. high conductivity

c. high permeability

d. high permittivity

12. For a 3 phase synchronous generator with zero

pf leading load, the terminal voltage due to

armature reaction

a. increases

b. decreases

c. does not change

d. comes down to zero volts

13. Which of the following equipments is

generally used for power factor correction in

industrial plants?

a. 3 phase induction motor

b. 3 phase synchronous motor

c. DC series motor

d. DC shunt motor

14. The maximum demand, load factor and the

plant rated capacity of a generating station are

100 MW, 0.65 and 130 MW, respectively. The

daily energy produced in the station is

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a. 1560 MWhr

b. 2028 MWhr

c. 2400 MWhr

d. 3120 MWhr

15. Which of the following water turbines is of

impulse type?

a. Pelton turbine

b. Francis turbine

SECTION-II

QUESTION NUMBER 1-20

CARRY 1 MARK EACH

c. Kaplan turbine

d. Deriaz turbine

16. The receiving end voltage of a 20

km1origoverhéad transmission line is to be

kept constant at 10 kV. Its voltage regulation

is 20% with a load. If a capacitor is connected

in parallel with the load to reduce the

regulation to 10%, the sending end voltage is

a. 9 kV

b. 10 kV

c. 11 kV

d. 12 kV

17. For an n-p-n silicon BJT operating in the

active region with grounded emitter, if the

equivalent base voltage and the equivalent

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respectively, its base current is

a. 0.07 mA

b. 0.1 mA

c. 0.17 mA

d. 1 mA

18. The B

equivalent to a two-input

a. NAND gate

b. NOR gate

c. X-OR gate

d. X-NOR gate

19. In a multi-stage R-C coupled amplifier, the

coupling capacitor

a. limits the low frequency response

b. limits the high frequency response

c. does not affect the frequency response

d. blocks the DC components without

affecting the frequency response

20. The minimum number of MOS transistors

required to make a dynamic RAM cell is

a. 1

b. 2

c. 3

d. 4

21. The range of the address of the RAM which is

interfaced to a microprocessor as shown in

Fig. 11.21 is

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a. 1400—17FF

b. E400—EFFF

c. F000—FFFF

d. F400—F7FF

22. After the execution of the following program

in the 8085 microprocessor, the contents of the

accumulator are

Address Code Mnemonics

203A 3E 20 MVI A, 20H

203C 2A 3A 20 LHLD 203AH

203F 86 ADD M

2040 76 HLT

a. 20H

b. 40H

c. 5EH

d. 7CR

23. For a single tone AM wave, if the modulation

index is 1/2, the ratio of the power in the

sidebands to that in the entire modulated wave

is

a. 1/9

b. 1/8

c. 1/4

d. 1/2

24. For a single tone FM wave with a maximum

frequency deviation of 75 kHz and the

modulation frequency of 15 kHz, the

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transmission bandwidth is

a. 90 kHz

b. 120 kHz

c. 150 kHz

d. 180 kHz

25. If the codeword length of a PCM system is

increased from 8 bits to 9 bits, the

corresponding signal to quantization noise

ratio gets improved by

a. 0 dB

b. 6 dB

c. 8 dB

d. 9 dB

26. In time division multiplexing (TDM),

a. input and output commutators need not be

synchronized

b. each signal is sampled below Nyquist rate

c. different signal samples are interleaved

and a single composite signal is

transmitted over the channel

d. the signals are collected at the receiving

end without any filtering

27. A half-wave controlled rectifier connected to a

sinusoidal input source of peak amplitude 300

V supplies power to a resistive load at a firing

angle of 120°. The ratio of its average load

voltage to the supply peak voltage is

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a. 1

b. 1

QUESTION NUMBER 20-50

CARRY 2 MARKS EACH

c. 1

d. 2

28. A fully controlled bridge rectifier with

resistive load is connected to a Y-Y

transformer having RMS value of the

secondary from phase to neutral of 300 V. If

the firing angle is 30°, then average load

voltage will be

a. 607.70 V

b. 350.86 V

c. 248.09 V

d. 202.57 V

29. A 1-phase to 1-phase cycloconverter is having

a resistive load connected to the centre tap of

the secondary of the source transformer. The

input source gets short circuited when

a. firing angle of each thyristor is 0°

b. firing angle of each thyristor is 90°

c. load voltage frequency is not a

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submultiple of the source voltage

frequency

d. load voltage frequency is submultiple of

the source voltage frequency

30. A multiple rectangular pulse-modulated

inverter with 250V and 50 Hz has 20 pulses

per cycle locked with the inverter output

frequency. The frequency of pulses is

a. 1000 Hz

b. 500 Hz

c. 250 Hz

d. 50 Hz

31. Fig. II.31 shows the circuit of an ideal

chopper. Assuming no ripple in the output and

the duty cycle of the switch to be D, the

average load voltage across the load RL

becomes

a. E

b. DE

c. E/(1-D)

d. E(1-D)

32. Fig. II.32 shows a switched capacitor where

the switches S1 and S2 are alternatively closed

and opened at a frequency of 1 kHz.

equivalent resistance becomes

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33. A 400 V, 60 Hz, 3 phase induction motor is

drawing 60 A at 0.85 pf lagging. The stator

and the rotor copper losses are 2 kW and 1

kW, respectively. If the core losses are 1.5 kW

then the air gap power is

a. 30.83 kW

b. 31.83 kW

c. 37.44 kW

d. 57.69 kW

34. A 500 kVA, 11000/400 V tap changing

transformer is used to regulate the voltage in a

distribution network. The voltage ratio of this

transformer at 2% tap change is

a. 11220/408

b. 11220/400

c. 220/8

d. 10780/392

35. A long shunt DC compound generator drives

parallelly connected 20 lamps, each having a

shunt resistance, armature resistance and series

generated emf is

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a. 505 V

b. 502.5 V

c. 497.5 V

d. 495 V

36. A 250 V DC shunt motor has armature

resistance of

develops a back emf of 242 V at 1500 rpm.

The armature current at the time of starting is

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a. 80 A

b. 250 A

c. 2500 A

d. 2525 A

37. A 220 V DC series motor running at 800 rpm

takes a current of 20 A and develops a back

emf of 200 V. The motor has armature

same current of 20 A, the external resistance to

be connected in series with the armature is

38. An induction motor operating at 0.8 pf lagging

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is consuming 300 kW. A zero real power

consuming synchronous motor is connected

across the induction motor to raise the pf to

0.92 lagging. The reactive power drawn by the

synchronous motor is

a. - 352 kVAR

b. - 225 kVAR

c. - 127.8 kVAR

d. - 97.2 kVAR

39. An interconnector cable having a reactance of

j0.05 pu links two generating stations G1 and

G2 as shown in Fig. II.39 where |V1| = |V2| = 1

pu. The load demands at two buses are SD1 =

15 + j5 pu and SD2 = 25 + j15 pu. The total

reactive power (in pu) at the generating station

a. 25.68

b. 25

c. 5.68

d. 5

40. A 10 MW generator is connected to load

through a transmission line. If the incremental

cost of production is dF 0.1P 3

dP

and loss in transmission line is 1 MW, the

incremental cost of received power in

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Rs./MWhr is

a. 5.44

b. 5

c. 4.44

d. 4

41. An IDMT relay of rating 5A, 2.2s and having

a relay setting of 125% is connected to a

supply circuit through a CT having a ratio of

400/5. The plug setting multiplier of IDMT

relay in the event of fault current of 4000 A

will be

a. 5

b. 8

c. 10

d. 125

42. A 2.5 kVA, 100/400 V single phase

transforme

measured from the primary side. The leakage

reactance (in pu) measured from the secondary

side of the transformer is

a. 0.96

b. 0.9

c. 0.015

d. 0.1

43. A single phase 50 Hz generator supplies an

inductive load of 5000 kW by means of a 20

km long overhead transmission line whose

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is required to be kept constant at 10 kV. The

efficiency of transmission line when pf of load

is improved to 0.9 lagging is

a. 98.08%

b. 97.64%

c. 82.1%

d. 78.83%

44. Two generating stations G1 and G2 of ratings

10 MVA and 8 MVA respectively are linked

by a line rated at 5 MVA, 0.1 Pu reactance.

Each station has a reactance of 0.5 pu. If the

base MVA is 10 MVA, short-circuit MVA of

G1 is

a. 36.6

b. 34.28

c. 32.15

d. 10

45. If a bias voltage of VT (in V) is applied to a

forward-biased silicon p-n junction diode with

a non-ideality coefficient of 2, the diode

current (in A) shall be

a. 0 I

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c. 0 eI

46. Assuming the forward diode drop as 0V, the

output voltage V0, as shown in Fig. II.46, is

a. 0 V

b. 5 V

c. 3.5 V

d. 6.5 V

47. Two two-port networks are connected in

cascade. The combination is to be represented

as a single two-port network. The parameters

of the network are obtained by multiplying the

individual

a. z-parameter matrix

b. h-parameter matrix

c. y-parameter matrix

d. ABCD-parameter matrix

48. For the ideal OP-AMP shown in Fig. II.48, the

output voltage V0 is

a. 2 V

b. 6 V

c. 10 V

d. 20 V

49. How many minimum number of NOR gates

are required to realize a two-input X-OR gate?

a. 2

b. 3

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c. 4

d. 5

50. The sequential circuit shown in Fig. II.50 will

act as a

a. Mod—1 counter

b. Mod—2 counter

c. Mod—3 counter

d. Mod—4 counter

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1. Chandrayaan-I, India’s first mission to the

moon, has 11 scientific instruments that are

being released on the surface of the moon.

These instruments are together known as

a. Moon Impact Probes

b. Terrain Mapping Cameras

c. Scientific Payloads

d. Spectrometers

2. The World Wide Web was invented by

a. Tim Berners-Lee

b. Narayanmurthy

c. Sabeer Bhatia

d. Charles Babbage

3. How many diagonals does a quadrilateral

have?

a. one

b. two

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c. four

d. eight

4. ISO 14000 standards deal with

a. quality management

b. production management

c. human resource management

d. environmental management

5. Which Indian politician’s autobiography is

titled The Story of My Life?

a. Morarji Desai

b. Mahatma Gandhi

c. Lal Krishna Advani

d. Atal Behari Vajpayee

6. The phrase ‘through thick and thin’ means

a. big and small

b. thin and fat

c. large object

d. under all conditions

7. Picturesque means

a. photogenic

b. simple

c. stimulating

d. ugly

8. Diligent means

a. intelligent

b. energetic

c. modest

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d. industrious

9. The opposite of miserly is

a. spendthrift

b. generous

c. liberal

d. charitable

10. The opposite of ingratitude is

a. sympathy

b. reward

c. thankfulness

d. stimulation

11. The appropriate missing word in the blank

space in the sentence “I prefer coffee _____

tea.” is

a. than

b. over

c. for

d. to

12. The appropriate missing word in the blank

space in the sentence “Many relatives attended

_________ him during his illness.”

a. of

b. on

c. for

d. with

13. The article required before the word “oneeyed”

in the sentence “There was ________

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one-eyed beggar by the multiplex.” is

a. the

b. a

c. an

d. nil

14. The article required before the word

University in the sentence “She met Professor

Shah at ________________University.” is

a. a

b. an

c. the

d. nil

15. Which one is the correct sentence amongst the

following sentences?

SECTION - III

ALL QUESTIONS CARRY

1 MARK EACH

a. Mr. Gupta, accompanied by his friends,

were assembled on the lawns.

b. Mr. Gupta, accompanied by his friends,

are assembled on the lawns.

c. Mr. Gupta, accompanied by his friends,

assembled on the lawns.

d. Mr. Gupta, accompanied by his friends,

have assembled on the lawns.

16. Who was the first woman to be elected as the

President of the Indian National Congress?

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a. Sarojini Naidu

b. Sonia Gandhi

c. Indira Gandhi

d. Annie Besant

17. Which political leader delivered the famous ‘I

have a dream’ speech?

a. Jawaharlal Nehru

b. Winston Churchill

c. Martin Luther King

d. Rabindranath Tagore

18. Who established the organization ‘Khudai

Khdmatgar’?

a. Hyder Ali

b. Gopal Krishna Gokhale

c. Maulana Abul Kalam Azad

d. Khan Abdul Ghaffar Khan

19. Analgesics are drugs used to prevent or relieve

a. aches and pain

b. fever and high body temperature

c. hormone deficiency

d. stress and anxiety

20. The abbreviation CD stands for

a. Circular Disc

b. Computer Device

c. Compact Disc

d. Code-Demodulator

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1. Q-meter works on the principle of

a. series resonance

b. parallel resonance

c. mutual inductance

d. self inductance

2. The bridge circuit shown in Fig. Q2-I

a. cannot be balanced

b. can be balanced but the frequency of

excitation must be known

c. can be balanced for only one frequency

d. can be balanced at any frequency

3. Which one of the following statements is

TRUE for an ‘ideal’ power diode?

a. Forward voltage drop is zero and reverse

saturation current is non-zero.

b. Reverse recovery time is non-zero and

reverse saturation current is zero.

c. Forward voltage drop is zero and reverse

recovery time is zero.

d. Forward voltage drop is non-zero and

reverse recovery time is zero.

4. In a MOSFET, the pinch-off voltage refers to

a. drain-to-source voltage at which drain-tosource

current is zero

b. gate-to-source voltage at which gate-tosource

current is zero

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c. drain-to-source voltage at which gate-tosource

current is zero

d. gate-to-source voltage at which drain-tosource

current is zero

5. Which of the following statements is TRUE

for DC switched mode power supply?

a. It cannot provide isolation between input

and output as in rectifiers.

b. It cannot remove ripple as in DC

switching mode regulators.

c. It has two stage conversions: dc-ac and acdc.

d. It is a type of chopper circuit.

6. Which one of the following is a ceramic

insulator?

a. Mica

b. Porcelain

c. Liquid crystal

d. Synthetic fiber

7. Which one of the following represents a direct

band-gap material?

a. Si

b. Ge

c. GaP

d. GaAs

8. Which one of the following statements is NOT

true?

a. Rochelle salt exhibits ferroelectric

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property.

b. Spontaneous polarization is a

characteristic property of ferroelectric

material.

c. Spontaneous polarization of ferroelectric

materials usually vanishes below

ferroelectric Curie temperature.

d. Ferroelectric materials exhibit hysteresis

effect.

9. Which one of the following diodes contains a

metal-semiconductor junction?

a. Tunnel diode

b. Zener diode

c. Schottky diode

d. Gunn diode

10. Which one of the following statements is NOT

true?

a. Ferrites can be used in transformer cores

only at very low frequencies.

b. Ferrites are ferrimagnetic material.

c. Ferrites show spontaneous magnetization

below certain temperature.

d. DC resistivity of ferrites is many orders of

ten higher than that of iron.

11. Which one of the following statements is NOT

true?

Set-D TELECOM

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BSNL JTO (TC) 2009

SECTION - I

QUESTION NUMBER 1- 20

CARRY 1 MARK EACH

a. In an intrinsic semiconductor,

concentration of electrons in the

conduction band is same as the

concentration of holes in the valance band.

b. The probability of an energy state at the

Fermi level being occupied by an electron

is 1/2.

c. Mobility of electrons is higher than that of

holes.

d. In an n-type semiconductor, concentration

of holes is equal to that of the intrinsic

concentration.

12. ABCD parameters of a two-port network is

defined as 1 2

1 2

.

V A B V

I C D I

If the port-2 is

terminated by a resistance RL, the admittance

looking into the port-1 is

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13. The phenomenon of injection electroluminescence

is the basis of working of

a. photodiodes

b. light emitting diodes

c. phototransistors

d. solar cells

14. A parallel combination of N resistances is

connected across an ideal current source of I

Amperes. The expression for the current in the

kth resistor Rk is

15. In the circuit shown in Fig. Q15-I, the voltage

across the terminals AB (in Volt) is

a. 5/30°

b. 12.5/30°

c. 17/30°

d. 25/30°

line of characteristic impedance Z0 is

terminated to a load of impedance ZL as shown

in the Fig. Q16-I. The input impedance as seen

at the other end is

a.

0

L Z

Z

b. ZL

c. ZLZ0

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d.

2

0

L Z

Z

17. A microstrip line has a strip width W and a

grounded dielectric substrate of thickness d

following statements is NOT true?

function of W

d

c. The characteristic impedance of the line is

a function of W

d

d. The line can support pure TEM mode of

wave propagation.

18. For a rectangular waveguide of internal

wave propagation with the lowest cut off

frequency is

a. TE01

b. TE10

c. TE11

d. TM11

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19. The mo

radiation resistance of a quarter wave

monopole antenna is

a. 36.5

b. 50

c. 73

d. 120

20. Which one of the following is an active

transducer?

a. Photo-voltaic cell

b. Strain gauge

c. Photo-emissive cell

d. Synchro

is to be converted to a 1 A ammeter by using a

shunt resistance. Which one of the followings

is the most appropriate shunt resistance?

22. The forward voltage drop of a power diode is

VD = 1.0 V at the diode current ID = 200 A.

thermal voltage VT = 25.7 mV, the reverse

saturation current Is (approximate) is

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23. In the circuit shown in Fig. Q23-I, the voltage

magnitude of percentage error in the

measurement is

a. 10

b. 20

c. 30

d. 40

24. Fig. Q24-I shows some load voltage versus

load current plots. Which one of them is NOT

valid for the classification of dc-dc converters?

a. P

b. Q

c. R

d. S

25. Two single phase inverters, one half-bridge

and the other full-bridge, operating with equal

inputs delivering power to identical loads. The

ratio of, the power delivered, the first

harmonic voltage and the total harmonic

distortion, for full-bridge inverter to halfbridge

inverter, respectively, are

a. 4, 2, 1

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b. 4, 2, 2

c. 4, 1, 1

d. 2, 1, 1

26. The correct match between Column A and

Column B is

Column A

1. DC Switch

2. Regulated DC-DC

3. AC-to-AC

4. DC-to-AC

Column B

R. Inverter

S. MOSFET

P. Boost Converter

Q. Cycloconverter

a. 1-R, 2-Q, 3-P, 4-S

b. 1-S, 2-P, 3-Q, 4-R

c. 1-P, 2-R, 3-Q, 4-S

d. 1-S, 2-Q, 3-P, 4-R

27. For the power transistor circuit shown in Fig.

Q27-

With an overdrive factor of 2.5, the required

resistance RB for saturation is

QUESTION NUMBER 21-50

CARRY 2 MARKS EACH

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28. For a lossless air-filled cubical cavity of

internal dimension 5 cm on each sides, the

resonant frequency for the TE101 mode is

a. 5 2 GHz

b. 5 GHz

c. 3 2 GHz

d. 3 GHz

29. Which one of the following statements is NOT

true?

a. For SCRs to be in the conduction state, the

forward anode current must be greater

than the latching current.

b. For SCRs to be in the forward blocking

state, the forward anode current must be

lower than the holding current.

c. When SCRs are in the conduction state,

they can be turned off by applying suitable

gate pulses.

d. When avalanche breakdown takes place,

SCRs enter into the conduction state.

30. Consider two metallic wires W1 and W2. They

are made up of same material and each has

circular cross section. The diameter of W2 is

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twice that of W1 and the length of W2 is four

times that of W1. Which one of the following

statements is TRUE?

a. Resistance of W1 is half that of W2

b. Resistance of W1 is equal to that of W2

c. Resistance of W1 is twice that of W2

d. Resistance of W1 is eight times that of W2

31. A current of 1 A flows through a circular loop

of superconducting wire having mean diameter

of 1 m, cross section area of 1 mm2 and self

-7 H. The current reduces

to 0.99 A after 1 year. The resistivity of the

wire is

a. 1.275 x 10-

b. 1.275 x 10-

c. 1.275 x 10-

d. 1.275 x 10-

32. An npn transistor is operating in CE mode and

carries a collector current Ic = 1 mA when the

collector to emitter voltage VCE = 1 V. If the

early voltage for the transistor is 74 V and

base to emitter voltage VBE is kept constant, at

VCE = 11 V the collector current is

a. 15/19 mA

b. 1 mA

c. 19/15 mA

d. 19/12 mA

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33. Two parallel plate capacitors shown in Fig.

Q33-I (a) and Fig. Q33-I (b) have capacitances

C1 and C2, respectively. If C2 = 2 C1, which

one of the following relations is TRUE?

(Neglect fringing effect)

a.

4

b.

2

c.

3

d. 2

3

34. A doped semiconductor specimen has Hall

coefficient 3.6 x 10-4 m3C-1 and the resistivity

9 x 10-

conduction, the mobility and density of

carriers in the specimen, respectively, are

(approximately)

a. 0.04 m2 V-1 s-1 and 1.74 x 1022 m-3

b. 0.4 m2 V-1 s-1 and 1.74 x 1022 m-3

c. 0.04 m2 V-1 s-1 and 1.74 x 1018 m-3

d. 4.0 m2 V-1 s-1 and 1.74x10-8 m-3

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concentration, intrinsic concentration, mobility

of electrons and mobility of holes, the

minimum conductivity of a semiconductor

sample occurs at

a. p

i

n

n n

b. n

i

p

n n

36. GaAs has bandgap energy of 1.42 eV. The

material would produce photon output at a

wavelength of (Planck s constant = 6.625 x 10-

34 J-s, q = 1.6 x 10-19 C)

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37. At a frequency of 1 GHz, the equivalent

represents wavelength) short-circuited lossless

38. For the circuit shown in Fig. Q38-I, the

If VC is to be set at 7.5 V, the required value

s

a. 172

b. 136

c. 100

d. 82

39. A quarter wave matching transformer is used

characteristic impedance of the quarter wave

matching section is

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40. If the average power delivered to a load

terminated to a lossless transmission line is

75% of that of the incident power, the VSWR

on the line is

a. 1/3

b. 1

c. 2

d. 3

41. For the circuit shown in Fig. Q41-I, a value of

ource would

deliver 50% of the maximum deliverable

power, is

a. 1

b. 0.5

c. 0.25

42. In the circuit shown in Fig. Q42-I (a), the

current I1 = 2 A. The current I2 in Fig. Q42-I

(b) is

a. -6A

b. -4A

c. 4A

d. 6A

43. In the circuit shown in Fig. Q43-I, the current I

a. -94.34 mA

b. -70.34 mA

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c. 70.34 mA

d. 94.34 mA

44. For the circuit shown in Fig. Q44-I, the

Thevenin’s voltage and resistance at terminals

A and B, respectively, are

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45. In the circuit shown in Fig. Q45-I, the switch

closes at t = 0. Assuming steady state

condition for t = 0-, the current iL at t = 0.15

sec is (approximately)

a. 0.04 A

b. 0.5 A

c. 0.76 A

d. 1.60 A

46. A PMMC instrument has a coil of dimensions

10 mm x 10 mm and the flux density in the air

gap is 2 mW/m2. The coil has 100 turns. If a

current of 5 mA produces an angular

deflection of 90°, the spring constant of the

instrument is

a. 2 10 8

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-m/rad

b. 10 8

2

-m/rad

-m/rad

d. 1 10 8

-m/rad

47. In the circuit shown in Fig. Q47-I, assume the

diodes are ideal and the ammeter is an average

indicating meter with zero internal resistance.

The ammeter reading is

a. 0.4 mA

b. 0.8 mA

c. 0.4

2

mA

d. 0.8

2

mA

48. A capacitive transducer uses two quartz

diaphragms of area 550 mm2 each separated

by a distance of 3.7 mm. A pressure of 750

kN/m2 applied to the top diaphragm produces

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a displacement of 0.7 mm. The capacity is 390

pF when no pressure is applied to the

diaphragm. The value of the capacitance after

the application of pressure of 750 kN/m2 is

a. 400 pF

b. 451 pF

c. 481 pF

d. 500 pF

and has a temperature coefficient of -

This thermistor is used to measure the

temperature of a system by the arrangement

shown in Fig. Q49-I. If the system temperature

falls to 20°C, the VAB measured by the

voltmeter is

a. -10/29 V

b. -15/29V

c. 10/29 V

d. 15/29 V

50. For the circuit shown in Fig. Q50-I, if the

current I = 3 A, then the voltage V2 is

a. 2.5 V

b. 5 V

c. 8 V

d. 10 V

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1. Which one of the following statements is NOT

true for a TWT?

a. The interaction region usually consists of a

slow wave helix structure.

b. A static axial magnetic field keeps the

electron beam focused.

c. Continued interaction takes place between

the waves on a traveling wave structure

and the electron beam.

d. TWT amplifiers are suitable only for

narrowband microwave communication

systems.

2. The minimized form of the Boolean

3. Number of address lines required to address 8

k bytes of memory is

a. 13

b. 14

c. 15

d. 16

4. The standard binary code for alpha numeric

characters is

a. ASCII

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b. GRAY

c. BCD

d. Excess-3

5. The 2’s complement of the binary number

1101100 in BCD is

a. 12

b. 13

c. 14

d. 15

6. In the op-amp circuit shown in Fig. Q6-II, the

voltage ratio V0/Vi is

a. - 2

b. - 1

c. - 0.5

d. 0.5

7. For the Schmitt trigger circuit shown in Fig.

Q7-II, assuming diodes and op-amp are ideal,

the values of lower and upper threshold points

of voltage transfer characteristics, respectively,

are

a. - 8V, + 5V

b. - 5V, + 5V

c. - 5V, + 8V

d. - 8V, + 8V

8. Which one of the following Boolean

expressions is NOT correct?

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9. A Boolean function can be expressed

a. as sum of maxterms or product of

minterms

b. as product of maxterms or sum of

minterms

c. partly as product of maxterms and partly

as sum of minterms

d. partly as sum of maxterms and partly as

product of minterms

10. Among the following logic families, the one

having the lowest power dissipation and

highest noise margin is

a. Schottky TTL

b. TTL

c. ECL

d. CMOS

11. The characteristic equation of a level triggered

T flip-flop, with T as input and Q as output is

loop control system encloses the point (-1, j0)

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in GH-plane. The gain margin of the system in

dB, is

SECTION- II

QUESTION NUBER 1-20

CARRY 1 MARK EACH

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a. greater than zero

b. less than zero

c. zero

d. infinite

13. For the LTI system described by

2

2 2 3 4 2 1

d y t dy t

y t r t r t

dt dt

having zero initial conditions, the transfer

Y s

R s

is

14. An amplitude modulated double sideband

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suppressed carrier signal is given by

the frequency of the carrier signal. The

modulating signal is

f t

15. Which one of the following expressions

represents a frequency modulated signal?

16. A binary pulse communication system

transmits a normalized pulse p(t) over bit

duration Tb. If the pulse p(t) has Fourier

transform P(f), the condition for zero

intersymbol interference in the absence of

noise is

ans:-??

17. The magnitude response of an ideal equalizer

for rectifying a distortion characterized by

18. If the minimum sampling frequency required

to reconstruct a band limited analog signal

from its samples is 8 kHz, the maximum

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frequency present in the signal is

a. 16 kHz

c. 4 kHz

d. > 4 kHz

19. Which one of the following statements is NOT

true?

a. The two cavity klystron tube is used as an

amplifier.

b. A reflex klystron uses only a single cavity

and operates as an oscillator.

c. In klystron tubes, the bunching of

electrons is caused by velocity

modulation.

d. Klystrons belong to the category of

crossed-field tubes.

20. In a microprocessor, the program counter

points to the address location from where the

a. current byte is to be fetched

b. next byte is to be fetched

c. next byte is to be stored

d. current byte is to be added

21. A microwave link operates under free space

conditions at a frequency of 1 GHz and uses

identical antennas at the transmitter and the

receiver ends. The transmitter and the receiver

are separated by a distance of 30 km. If -30

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dBm power is to be received when the

transmitted power is 1 W, the antenna gain

should be

22. In connection with memory mapped 110

which one of the following statements is NOT

true?

a. The processor treats an interface register

as a part of the memory system.

b. It reduces the memory space available.

c. The processor cannot manipulate I/O data

residing in interface registers with the

QUESTION NUMBER 21-50

CARRY 2 MARKS EACH

same instructions that are used to

manipulate memory location.

d. Arithmetic or logical operation can be

directly performed with I/O data.

23. After execution of the following C program,

the value of the sum printed is

a. 68

b. 20

c. 16

d. 4

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24. If selection sort takes 3 ms to run an array of

200 elements, for a similar array of 4000

elements the selection sort is expected to take

a. 1.2 s

b. 600 ms

c. 300 ms

d. 60 ms

25. In a stack based processor organization,

postfix notation is used for evaluating

arithmetic expressions. The postfix expression

ABC*/D-EF/+ for A = 6, B = 2, C = 3, D = 3,

E = 4 and F = 2 evaluates to

a. 0

b. 1

c. 2

d. 3

26. In a 8085 microprocessor system, the active

low chip select (CS) signal is generated by

passing address lines A15, ...., A10 through a 6

inputs NAND gate. For selecting the address

range CC00 to CFFF, the inputs to the NAND

gate are

a. A10 , A11, A12 , A13 , A14 , A15

b. 10 11 12 13 14 15 A , A , A , A , A , A

c. 10 11 12 13 14 15 A , A , A , A , A , A

d. 10 11 12 13 14 15 A , A , A , A , A , A

27. in the context of 8085 microprocessor, the

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correct matching combination between

Column A and Column B is

Column A

P. ALE

Q. PSW

R. CMA

S. RLC

Column B

1. Rotate accumulator left

2. Compare with accumulator

3. Program status word

4. Address latch enable

5. Program stack word

6. Arithmetic logic enabled

7. Complement accumulator

8. Rotate accumulator left through carry

a. P-6, Q-5, R-2, S-8

b. P-4, Q-3, R-2, S-8

c. P-4, Q-3, R-7, S-1

d. P-6, Q-5, R-7, S-1

28. The content of the memory location 2070 H

after the execution of the following 8085

program is

LXIB 2070H

MVI A, 8FH

MVI C, 68H

SUB C

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ANI OFH

STAX B

HLT

a. 04 H

b. 07 H

c. 09 H

d. 0F H

29. A 8085 microprocessor program uses all

available Jump instructions, each only once.

For this program, the total memory (in Bytes)

occupied by the Jump instructions is

a. 30

b. 27

c. 24

d. 18

30. The circuit shown in Fig. Q30-II oscillates at

respectively, are

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a. 105 and 20

b. 2 × 105 and 20

c. 2 × 105 and 10

d. 105 and 10

31. A combinational circuit accepts a 2 bit binary

number and outputs its square in binary. To

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design this circuit using a ROM, the minimum

size of ROM required is

a. 2 × 2

b. 4 × 2

c. 4 × 4

d. 8 × 4

32. In the op-amp circuit shown in Fig. Q32-II,

assume the diode current follows the

equation V /VT

relation between 01 02 V and V is

b. 2 1

2

33. In the 2-stage amplifier circuit shown in Fig.

Q33-II, if the transconductances of transistor

Q1 and transistor Q2 are gm1 and gm2,

respectively, the overall transconductance gm0

= i0/vi of the amplifier is

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4

1

K s

G s H s

s s

, the

breakaway points in the root-loci plot

approximately are

a. – 7.46, – 1

b. – 0.54, – 1

c. – 7.46, – 0.54

d. 7.46, 0.54

35. For the circuit shown in Fig. Q35-II, the pchannel

JFET transistor parameters are IDSS =

6 mA and VP = 4 V. The source-to-drain

voltage VSD and the region of operation of the

transistor, respectively, are

a. 2.09 V and active region

b. 2.09 V and saturation region

c. 2.47 V and active region

d. 2.47 V and saturation region

36. For the truth table given in Fig. Q36-II, the

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minimized Boolean expression is

Input Output

x y z p

0 0 0 1

0 0 1 0

0 1 0 0

0 1 1 1

1 0 0 0

1 0 1 1

1 1 0 1

1 1 1 0

Fig. Q36-II

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37. For a linear system having the characteristic

equation s4 + s3 + 2s2 + 2s + 3 = 0, the number

of roots in the right-half of s-plane is

a. 4

b. 3

c. 2

d. 1

7) is to be implemented using a 4 × 1

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multiplexer shown in Fig. Q.38-II. Which one

of the following choices of inputs to

multiplexer will realize the Boolean function?

,0, A, A,C, B

39. An edge triggered synchronous binary counter

is provided with a clock (CLK) and control

load (L) and active high count (C). The correct

matching combination between Column A and

Column B is

Column A

where X = don’t care.

Column B

1. No change

2. Load inputs

3. Count next binary state

4. Clear outputs

A B C D

a. 2 3 4 1

b. 1 2 3 4

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c. 2 3 1 4

d. 1 2 4 3

40. A 5-bit serial adder is implemented using two

5-bit shift registers, a full adder and a D flipflop.

The two binary words to be added are

11011 and 11011. The sum of the two

numbers is stored in one of the shift registers

and the carry in the D flip-flop. Assuming that

the D flip-flop is set initially, the content of

the sum shift register and the D flip-flop,

respectively, are

a. 10111 and 0

b. 11011 and 1

c. 11101 and 0

d. 10111 and 1

41. For the flow diagram shown in Fig. Q41-II,

the transfer function

Y s

R s

is

a. 2

3

b. 2

3

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c. 2

3

d. 2

3

s 6s 11

42. The compensated system shown in Fig. Q42-

II, has a phase margin of 60o at the crossover

frequency of 1 rad/sec. The value of K is

a. 0.366

b. 0.732

c. 1.366

d. 2.732

43. A time division multiplex system samples 96

voice channels at a rate of 8 kHz and encodes

into 8 bits per sample. If one synchronization

bit per frame is added, the transmitted data rate

(Mbps) is

a. 6.208

b. 6.152

c. 6.144

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d. 0.768

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44. A geostationary satellite located at 36,000 km

from the surface of the earth. The uplink free

space loss is 1.583 dB higher than the

downlink free space loss. If the downlink

frequency is 10 GHz, the uplink free space

loss (in dB) is

a. 10.25

b. 20.5

c. 102.5

d. 205

45. In a uniform quantizer, the quantization noise

is

a. independent of the number of levels of the

quantizer

b. proportional to square of the peak-to-peak voltage range of the quantizer

c. independent of the peak-to-peak voltage

range of the quantizer

d. proportional to square of the number of

levels of the quantizer

46. In a digital communication system, the

transmitted pulse is shown in Fig. Q46-II. The

matched filter output at the sampling instant

(i.e., t = 1 sec) is

a.32

b. 1

c.12

d.16

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47. An optical link uses a fiber having a power

loss of 1 dB/km. A typical photo detector has

responsively 0.5 A/W. If the link is 3 km long

and the detector is required to produce a

power is

a. 0 dBm

b. – 10 dBm

c. – 30 dBm

d. – 50 dBm

48. For the directional coupler shown in Fig. Q48-

II, the coupling is 20 dB and the directivity is

30 dB. If 10 W power is incident in port-1,

power out of port-4 is

a. 0.1 mW

b. 1 mW

c. 0.01 W

d. 0.1 W

49. In a microwave measurement with slotted

rectangular waveguides, the distance between

successive minima is found to be 2.5 cm. If the

measurement has been carried out at a

frequency of 10 GHz and the guide operates in

TE10 mode, the cut off frequency fc10 for the

guide is

a. 6 GHz

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b. 8 GHz

c. 10 GHz

d. 12 GHz

50. An antenna having a directivity of 2 at a

frequency of 300 MHz will have a maximum

effective aperture of

a. 1 2 8 m

b. 2 14m

c. 1 22m

d. 2 1 m

1. Chandrayaan-I, India’s first mission to the

moon, has 11 scientific instruments that are

being released on the surface of the moon.

These instruments are together known as

a. Moon Impact Probes

b. Terrain Mapping Cameras

c. Scientific Payloads

d. Spectrometers

2. The World Wide Web was invented by

a. Tim Berners-Lee

b. Narayanmurthy

c. Sabeer Bhatia

d. Charles Babbage

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3. How many diagonals does a quadrilateral

have?

a. one

b. two

c. four

d. four

4. ISO 14000 standards deal with

a. quality management

b. production management

c. human resource management

d. environmental management

5. Which Indian politician’s autobiography is

titled The Story of My Life?

a. Morarji Desai

b. Mahatma Gandhi

c. Lal Krishna Advani

d. Atal Behari Vajpayee

6. The phrase ‘through thick and thin’ means

a. big and small

b. thin and fat

c. large object

d. under all conditions

7. Picturesque means

a. Photogenic

b. Simple

c. Stimulating

d. Ugly

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8. Diligent means

a. intelligent

b. energetic

c. modest

d. industrious

9. The opposite of miserly is

a. spendthrift

b. generous

c. liberal

d. charitable

10. The opposite of ingratitude is

a. sympathy

b. reward

c. thankfulness

d. stimulation

11. The appropriate missing word in the blank

space in the sentence “I prefer coffee

___________________ tea.” is

a. than

b. over

c. for

d. to

12. The appropriate missing word in the blank

space in the sentence “Many relatives attended

him during his illness.”

a. of

b. on

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c. for

d. with

13. The article required before the word “oneeyed”

in the sentence “There was

_____________ one-eyed beggar by the

multiplex.” Is

a. the

b. a

c. an

d. nil

14. The article required before the word

University in the sentence “She met Professor

Shah at __________ University” is

a. a

b. an

c. the

d. nil

SECTION - III

ALL QUESTIONS CARRY

1 MARK EACH

15. ‘Which one is the correct sentence amongst

the following sentences?

a. Mr. Gupta, accompanied by his friends,

were assembled on the lawns.

b. Mr. Gupta, accompanied by his friends,

are assembled on the lawns.

c. Mr. Gupta, accompanied by his friends,

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assembled on the lawns.

d. Mr. Gupta, accompanied by his friends,

have assembled on the lawns.

16. Who was the first woman to be elected as the

President of the Indian National Congress?

a. Sarojini Naidu

b. Sonia Gandhi

c. Indira Gandhi

d. Annie Besant

17. Which political leader delivered the famous ‘I

have a dream’ speech?

a. Jawaharlal Nehru

b. Winston Churchill

c. Martin Luther King

d. Rabindranath Tagore

18. Who established the organization ‘Khudai

Khidmatgar’?

a. Hyder Ali

b. Gopal Krishna Gokhale

c. Maulana Abul Kalam Azad

d. Khan Abdul Ghaffar Khan

19. Analgesics are drugs used to prevent or relieve

a. aches and pain

b. fever and high body temperature

c. hormone deficiency

d. stress and anxiety

20. The abbreviation CD stands for

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a. Circular Disc

b. Computer Device

c. Compact Disc

d. Code-Demodulator