*NEW! *** The Gist (JULY-24) | E-BOOKS**

# (Paper) MPPSC: Online Examination of State Engineering Service (Pre.) Exam - 2014 Second Paper (Electrical Engineering)

## (Paper) MPPSC: Online Examination of State Engineering Service (Pre.) Exam - 2014 Second Paper (Electrical Engineering )

## Electrical Engineering

**Q1 : The unit step sequence u[n] and impulse response [n] are related as -**

**Answer Key: D**

**Q2 : The system given as y(t)=x(t-8) is invertible then inverse system
will be as**

A y(t+8)

B y(t-8)

C y(2t+8)

D y(t-2)

**Answer Key: A**

**Q3 : **

A F(s)

B sF(s)–f(0)

C s^{2}F(s)

D s^{3}F(s)- f(0)

**Answer Key: B**

**Answer Key: A**

**Q5 : The discrete-time system denoted by y[n]=x[n ^{3}] is**

A Linear, time-varying and causal system

B Nonlinear, time-varying and causal system

C Linear, time-invariant and non-causal system

D Linear, time-variant and non-causal system

**Answer Key: D**

**Q6 : If the voltage gain |V _{0}/V_{i}| of an amplifier is
1/
, its value in dB is -**

A +10 dB

B -6.93 dB

C -3 dB

D +3 dB

**Answer Key: C**

**Q7 : The trigonometric Fourier series representation of an even signal
does not have the following type of functions **

ADC

B Cosine functions

C Sine functions

D Odd harmonic functions

**Answer Key: C**

**Q8 : The impulse response of a linear time invariant system is given by
h(t) =
(t-2)
+
(t-3). The step response of this system at t=1 will be -**

A 0

B 1

C 2

D 3

**Answer Key: A**

**Q9 : The power spectral density and the autocorrelation function of an
periodic signal are related by -**

A The Fourier transformation

B The Laplace transformationC Both are same

D None of these is correct

**Answer Key: A**

**Q10 : The power of a sinusoid signal x(t) = A/2 Cos(t)
is given by -**

A A^{2}/4

B A^{2}/2

C A^{2}

D A^{2}/8

**Answer Key: D**

**Q11 : Assume that F1 and F2 denote the lower and upper half power
frequencies of a series RLC circuit respectively and F0 denotes the resonance
frequency. The selectivity of this RLC circuit is given by**

**Answer Key: B**

**Q12 : If eight resistors of 8 Ohm resistance of each are connected in
parallel then the net resistance will be:**

A 1

B 64

C 4

D 8

**Answer Key: A**

**Q13 :**

A 0,0

B 0,2

C 5,0

D 0,5

**Answer Key: B**

**Q14 : The plot of the signal x(t) in the below figure represents:**

A Energy signal

B Power signal

C Energy signal and Power signal

D None of these is correct

**Answer Key: D**

**Q15 : Following is the magnitude of the impedance of the series RLC
circuit running at angular frequency : **

**Answer Key: D**

**Q16 : In the given circuit in the below Figure, the value of V will be as
follows:**

A 80

B 70

C 20

D 10

**Answer Key: A**

**Q17 : The superposition principle can not be applied for:**

A voltage computation

B current computation

C power computation

D bilateral components

**Answer Key: C**

**Q18 : If unit step current is applied to an initially relaxed capacitor,
then the voltage across the capacitor will be- A Unit step function**

B Ramp function

C Impulse function

D None of these is correct

**Answer Key: B**

**Q19 : The mathematical expression for the velocity for travelling
electromagnetic wave in free-space can be given as:**

**Answer Key: D**

**Q20 : The energy density corresponding to static magnetic field is as**

**Answer Key: B**

**Q21 : The SI unit of electrostatic field strength is**

A volt-meter

B volt2

/meter

C volt/meter

D volt/meter2

**Answer Key: C**

**Q22 : The equation
is**

A Maxwell’s equation

B Laplace’s equation

C Fourier equation

D Poisson’s equation

**Answer Key: D**

**Q23 : Poynting vector represents:**

A power density vector which produces electrostatic field

B current density vector which produces electrostatic field

C current density vector which produces electromagnetic field

D power density vector which produces electromagnetic field

**Answer Key: D**

**Q24 The distance between adjacent maxima and minima in a standing
wave of a transmission line is given by**

A
/4

B
/2

C
/8

D

**Answer Key: A**

**Q25 : The intrinsic impedance of free space is given by:**

A 20 Ohm

B 277 Ohm

C 177 Ohm

D 377 Ohm

**Answer Key: D**

**Q26 : The divergence of electric flux density
at origin is**

A 2

B 4

C -2

D 0

**Answer Key: A**

**Q27 : The input signal for the A.C. bridges is applied from**

A Oscillator system

B Amplifier system

C Regulated power supply system

D D.C. battery system

**Answer Key: A**

**Q28 : The internal resistance of the ammeter should be very low so that**

A It will have high sensitivity

B It will provide high accuracy

C It will provide maximum voltage drop across the meter

D It will provide minimum effect of the current in the circuit

**Answer Key: D**

**Q29 : The Wien bridge can be used for the following**

A Measurement of resistance

B Measurement of frequency

C Measurement of harmonic distortion

D Measurement of frequency and harmonic distortion

**Answer Key: D**

**Q30 : The application of thermocouple transducer is **

A Measurement of temperature B Measurement of velocity and vibration

C Measurement of pressure

D Measurement of gas flow

**Answer Key: A**

**Q31 : A varactor can be defined as**

A A diode which is used for variable capacitor

B A diode which is used for high speed switching

C A diode which is used for variable inductor

D A diode which is used for variable resistor

**Answer Key: A**

**Q32 : Measurement of dielectric loss of capacitor can be performed by**

A Using Wein bridge

B Using Owen bridge

C Using Schering bridge

D Using Maxwell bridge

**Answer Key: C**

**Q33 : Siemens can be used as a unit for**

A Measurement of conductance

B Measurement of resistance

C Measurement of flux density

D Measurement of electric field

**Answer Key: A**

**Q34 : A cathode ray oscilloscope works based on the following - **

A Electrostatic based focusing technique

B Electromagnetic based focusing technique

C Electrostatic and Electromagnetic based focusing technique

D None of these is correct

**Answer Key: A**

**Q35 : Regenerative feedback means the following**

A Feedback with step input

B Feedback with oscillations

C Feedback with positive sign

D Feedback with negative sign

**Answer Key: C**

**Q36 : Laplace transform is not useful for analysis of the following
control systems**

A Linear systems

B Discrete- time systems

C Time- invariant systems

D Unstable continuous –time systems

**Answer Key: B**

**Q37 : The transfer function of the following state model of an LTI system
with zero initial condition is**

**Answer Key: A**

**Q38 : The time period of a square ware of frequency 1kHz is**

A1 s

B 10 s

C 10^{-3} s

D 0.1 s

**Answer Key: C**

**Q39 : If the state space representation of an LTI system is known then the
transfer function of this system**

A Can be partially determined

B Can be completely determined

C Cannot be completely determined

D None of these is correct

**Answer Key: B**

**Q40 : What number of nybbles can make one byte**

A1

B 2

C 4

D 8

**Answer Key: B**

**Q41 : In a microprocessor, the data bus has 16 lines and address bus has
12 lines. What will be the number of bytes in the memory**

A 4k

B 2k

C 8k

D 24k

**Answer Key: A**

**Q42 : In Intel 8085 microprocessor, the address bus is 16 bit wide. The
memory which can be accessed by this address bus will be**

A 64 k bytes

B 2 k bytes

C 8 k bytes

D 12 k bytes

**Answer Key: A**

**Q43 : The following memory is a permanent memory**

A ROM

B RAM

C ROM AND RAM

D None of these is correct

**Answer Key: A**

**Q44 : The assumption of ergodic process in communication system means -**

A The random signals have identical time averages

B The random signals have identical ensemble averages

C The random signals have the identical time and ensemble averages

D None of these is correct

**Answer Key: C **

**Q45 : The power spectral density of the stationary noise whose
autocorrelation is R( )=e-3 | | , will be**

**Answer Key: D**

**Q46 : Entropy commonly measures :\**

A The average informtion

B The rate of information

C The probability of information

D The loss of information

**Answer Key: A**

**Q47 : The autocorrelation function of a signal at zero -lag will be :**

A Mean value of signal

B Average power of signal

C Average voltage of signal

D Zero

**Answer Key: B**

**Q48 : In DSB-SC system, at the receiver the detection process is expensive
because :**

A It requires synchronous detection

B Generation of local carrier is difficult at the receiver

C Power level of received signal is very low

D All options are correct

**Answer Key: A**

**Q49 : In a PCM system, the signal to quantization error ratio for 8-bit
words will be :**

A 54 dB

B 30 dB

C 40 dB

D 64 dB

**Answer Key: A**

**Q50 : Companding operation is useful because :**

A It overcomes quantization noise in PCM

B It protects small signals in PCM from quantizing noise

C It reduces impulse noise in PWM receivers

D None of these is correct

**Answer Key: B**

**Q51 : Which of the following pulse modulation technique is analog:**

A Differential PCM

B PCM

C PWM

D Delta

**Answer Key: C**

**Q52 : Frequency shift keying can be considered as a method for
introducing:**

A Frequency modulation

B Amplitude modulation

C Phase modulation

D None of these is correct

**Answer Key: A**

**Q53 : In a first order passive low-pass fifteen (R-C) circuit, the input
voltage square wave is fed. The output voltage, with respect to ground, is
measured across :**

A Supply

B Resister

C Capacitor

D Ground

**Answer Key: C**

**Q54 : The main disadvantage of CW Doppler radar is :**

A It does not provide the target velocity

B It does not provide target range

C It requires a transponder at the target

D It does not provide the target position

**Answer Key: B**

**Q55 : In an R-L series circuit, the ratio of inductive impedance to
resistance is 1/√3. The power factor of the A.C. circuit at steady state is:**

A 0.87 lag

B 0.87 lead

C 0.5 lag

D 0.5 lead

**Answer Key: A**

**Q56 : In television, we use interlacing for the following purpose:**

A To provide the illusion of motion

B To ensure that all lines on the screen are scanned

C To simplify the vertical sync pulse train

D To avoid flicker

**Answer Key: D**

**Q57 : Which statement is not true :**

A The phase array radar has very fast scanning compared to other types of
radar

B The phase array radar has ability to track and scan simultaneously compared to
other types of radar

C The phase array radar has circuit simplicity compared to other types of radar

D The phased array radar has the ability to track many targets simultaneously as
compared to other types of radar

**Answer Key: C**

**Q58 : The satellites used for the purpose of intercontinental
communications are called as: **

A Intelsat

B Damsat

C Comsat

D Marisat

**Answer Key: A **

**Q59 : A waveguide can be treated as a :**

A Low pass filter

B High pass filter

C Band pass filter

D Band stop filter

**Answer Key: B**

**Q60 : The radiation power of an antenna which has radiation resistance
equal to 500 ohm and fed by 20 A current, will be:**

A 100 kW

B 150 kW

C 200 kW

D 250 kW

**Answer Key: C**

**Q61 : What is the magnitude of the attractive force (in vacuum) between
the charge Q1 =3x10-4 C at location (1,2,3) and the charge Q2=-10-4 C at
location (2,0,5) ?**

A 120 N

B 60 N

C 40 N

D 30 N

**Answer Key: D**

**Q62 : A full- wave diode bridge rectifier circuit has : **

A 3 diodes

B 2 diodes

C 4 diodes

D 8 diodes

**Answer Key: C**

**Q63 : Which is not an Omni-directional antenna:**

A Marconi antenna

B Discone antenna

C Log-periodic antenna

D Half-wave dipole antenna

**Answer Key: C**

**Q64 : In order to separate the channels in an TDM receiver, we need to use
following :**

A Band pass filters

B And gates

C Differentiator

D Integrator

**Answer Key: B**

**Q65 : Which statement is not true ?**

A Losses in optical fibers can caused by impurities

B Losses in optical fibers can caused by microbending

C Losses in optical fibers can caused by attenuation in the glass

D Losses in optical fibers can caused by stepped index operation

**Answer Key: D**

**Q66 : Laser light is:**

A Coherent emission

B Stimulated emission

C Spontaneous emission

D Coherent and stimulated emissions

**Answer Key: D **

**Q67 : The core in optical fiber has following :**

A Less refractive index than the air

B Less refractive index than the cladding

C More refractive index than the cladding

D Same refractive index like cladding

**Answer Key: C **

**Q68 : The electrical torque in terms of supply voltage V in a 3-phase
induction motor, is proportional to the following?**

A V 2

B V-1

C V1/2

D V

**Answer Key: A**

**Q69 : The following motor is used for the compressors.**

A Reluctance motor

B DC series motor

C Shaded pole motor

D Capacitor-start capacitor-run motor

**Answer Key: D**

**Q70 : Which of the following statement is true ?**

A Single-phase induction motor requires only one winding

B Single-phase induction motor can rotate in one direction only

C Single-phase induction motor is self starting

D Single-phase induction motor is not self-starting

**Answer Key: D**

**Q71 : Which distortion is least significant for the audio amplifiers?**

A Frequency

B Phase

C Intermodulation

D Harmonic

**Answer Key: B**

**Q72 : The following relay is used for protection of motors against
overload?**

A Thermal relay

B Buchholz relay

C Impedance relay

D Electromagnetic attraction type

**Answer Key: A**

**Q73 : To charge a feeder cable the following sequence of operation is true
:**

A Make the isolator followed by make the switch gear

B Make the switch gear followed by make the isolator

C Simultaneously make the isolator and switch gear

D Break the isolator followed by make the switch gear

**Answer Key: A**

**Q74 : The fuse rating is given in terms of the following :**

A kVA

B VAR

C Voltage

D Current

**Answer Key: D**

**Q75 : Oil switches are applied :**

A For low current circuits

B For low voltage circuits

C For high voltages and large current circuits

D For all circuits

**Answer Key: C**

**Q76 : Which statement is true :**

A Reluctance motor can be considered as a variable torque motor

B Reluctance motor can be considered as low torque variable speed motor

C Reluctance motor can be considered as self starting type synchronous motor

D Reluctance motor can be considered as a low noise and slow speed motor

**Answer Key: C**

**Q77 : Which motor has series characteristics :**

A Shaded pole motor

B Capacitor start motor

C Repulsion motor

D None of these is correct

**Answer Key: C**

**Q78 : The variable speed operation is desired for the following
application :**

A Water pump

B Refrigerator

C Ceiling fan

D Exhaust fan

**Answer Key: C**

**Q79 : Given that X and Y are two independent Gaussian random variables,
each one has average value=0, and variance = , then the joint density function
can be defined as :**

A f(x,y) = (f(x))/(f(y))

B f(x,y) = f(x) f (y)

C f(x,y) = f(x) -f (y)

D f(x,y) = f(x) +f (y)

**Answer Key: B**

**Q80 : The material used for insulating in a cable should have the
following property :**

A Low cost

B High dielectric strength

C High mechanical strength

D All options are correct

**Answer Key: D**

**Q81 : If the length of a cable is doubled then its capacitance will be :**

A One-fourth

B One-half

C Double

D Remain unchanged

**Answer Key: C**

**Q82 : Which transmission system has skin effect absence, less line cost,
low corona effect?**

A HVDC

B EHV-AC

C UHB-AC

D HVDC and EHV-AC

**Answer Key: A**

**Q83 : The load curve is used for**

A Deciding schedule of generating units

B Deciding sizes of generating units

C Deciding total installed capacity of the plant

D Deciding schedule and sizes of the generating units and capacity of the plant

**Answer Key: D**

**Q84 : The circuit given below shows :**

A A logarithmic amplifier

B An integrator

C A differentiator

D A clamper

**Answer Key: A**

**Q85 : An ideal voltage amplifier has :**

A Input resistance = 0, Output resistance =

B Input resistance = 0, Output resistance = 0

C Input resistance = , Output resistance = 0

D Input resistance = , Output resistance =

**Answer Key: C **

**Q86 : Which statement is true :**

A A clipper circuit may generate harmonics B A clipper circuit increases the
RMS value of the signal

C A clipper circuit improves the power factor of the linear passive load

D A clipper circuit increases the load VA rating of the linear passive load

**Answer Key: A**

**Q87 : In order to sustain the oscillations, the Barkhausen criteria states
that :**

A The loop gain of the circuit should be negligible

B The loop gain of the circuit should be equal to 1 with phase shift 180 degree
lagging

C The phase shift around the circuit should be 90 degree lag

D None of these is correct

**Answer Key: B**

**Q88 : **

A T = XZ+X

B T= Z+XY

C T=X +XY

D T=X +X

**Answer Key: A**

**Q89 : Which interrupt is unmaskable interrupt ?**

A INTR

B RST 7.5

C TRAP

D RST 5.5

**Answer Key: C**

**Q90 : Gray code for number 4 is given by, **

A 0111

B 0110

C 0101

D 0100

**Answer Key: B**

**Q91 : Which relation is not true in Boolean algebra ?**

A A(BC) = (AB)C

B A(B + C) = AB + AC

C A + AC = A

D A(A + C) = 1

**Answer Key: D**

**Q92 : The value of **
**
of a BJT is : **

A >1

B about 0.1

C about 10-3

D about 10-5

**Answer Key: A**

**Q93 : The enhancement type MOSFET is known as : **

A N-type MOSFET

B P-type MOSFET

C Normally off MOSFET

D Normally on MOSFET

**Answer Key: C**

**Q94 : The following circuit is a sequential circuit :**

A AND gate

B NAND gate

C Bistable multivibrator

D EX-OR gate

**Answer Key: C**

**Q95 : The nature of transconductance curve of a JFET is :**

A Straight line

B Parabolic

C Hyperbolic

D Inverted V-type

**Answer Key: B**

**Q96 : Which diode works under forward-biased condition :**

A Photo diode

B Zener diode

C Light emitting diode

D Varactor diode

**Answer Key: C**

**Q97 : Which statement is true ?**

A Hall effect can be used to measure magnetic field intensity

B Hall effect can be used to measure electric field intensity

C Hall effect can be used to measure electric and magnetic field intensities

D Hall effect can be used to measure carrier concentration

**Answer Key: A **

**Q98 : The most heavily doped region of a transistor is :**

A Base

B Collector

C Emitter

D None of these is correct

**Answer Key: C**

**Q99 : Which is true statement ?**

A A bistable multivibrator is a free-running oscillator

B A bistable multivibrator is a triggered oscillator

C A bistable multivibrator is a saw tooth wave generator

D A bistable multivibrator is a crystal oscillator

**Answer Key: B **

**Q100 : BJT is considered better than MOSFET when :**

A There is a requirement of low cost

B There is a requirement of low power dissipation

C There is a requirement of high noise margin

D None of these is correct

**Answer Key: A **

## Printed Study Material for MPPSC

Courtesy : MPPSC