# ELECTRICAL ENGINEERING IMPORTANT 80 MCQ PDF FOR VIZAG MT EXAM 2017

1-The power consumed by an electrical device is
1000W at 250V. What is the resistance in the device?
(A) 60 ohm
(B) 250000 ohm
(C) 4 ohm
(D) 62.5 ohm
2-The capacitance of a parallel plate capacitor
increases with
(A) larger plate area and shorter distance
between plates
(B) smaller plate area and shorter distance
between plates
(C) smaller plate area and higher applied voltage
(D) larger plate area, larger distance between
plates and higher applied voltages
3-Two heaters of rating 1KW, 250V are connected
in series across 250V supply, the power taken by the heaters will be
(A) 2 KW
(B) ¼ KW
(C) ½ KW
(D) 1 KW
4-If V=a+jb and I=c+jd, then power is given by
(B) ac+bd
5-The ratio of charge stand by two metallic
spheres raised to the same potential is 6. The ratio of the surfaces areas of
the spheres is
(A) 6
(B) 1/6
(C) 1/√6
(D) 36
6-.B is based on
(A) Ampere’s law
(B) Ohm’s law
(D) Gauss’s law
7-The following law is synonymous to the
occurrence of diamagnetism
(A) Gauss’s law
(B) Lenz’s law
(C) Maxwell’s law
(D) Kirchoff’s law
8-The transfer function of an integral
compensator is given by
(A) 1/s
(B) 1/s2
(C) k/s
(D) None of the above
9-The following is the range of power consumption
in PMMC instrument.
(A) 0.25W to 2W
(B) 0.25mW to 2mW
(C) 25μW to 200μW
(D) 2W to 3W
10-Frequency can be measured by using
(A) Maxwell’s Bridge
(B) Schering Bridge
(C) Heaviside Campbell bridge
(D) Wein’s bridge
11-Maxwell’s inductance capacitance bridge is
used for measurement of inductance of
(A) low Q coils
(B) medium Q coils
(C) high Q coils
(D) low and medium Q coils
12-The following amplifier configuration yields
the largest power gain of all transistor amplifier configurations.
(A) Common base
(B) Common emitter
(C) Common collector
(D) Emitter base
13-Which family of logic circuits used FETs?
(A) TTL
(B) CMOS
(C) Both TTL and CMOS
(D) None of the above
14-Common Mode Rejection ratio (CMRR) for a
differential amplifier is the ratio of
(A) Differential gain / Common mode gain
(B) Differential gain / Integrated gain
(C) Integrated gain / Differential gain
(D) Common mode gain / Differential gain
15-Which of the following is the most stable
oscillator?
(A) Wein’s bridge oscillator
(B) Hartley’s oscillator
(C) Colpitt’s oscillator
(D) Crystal oscillator
16-The number of bits needed to address 4kb
memory is
(A) 6
(B) 8
(C) 12
(D) 16
17-The generation of harmonics in transformer is
mainly due to
(B) Poor insulation
(C) Mechanical vibrations
(D) Saturation of core
18-If the capacitor of a single phase motor is
short circuited
(A) The motor will not start
(B) The motor will run
(C) The motor will run in reverse direction
(D) The motor will run in the same direction at
reduced RPM
19-A chopper can be used on
(A) Pulse width modulation only
(B) Frequency modulation only
(C) Amplitude modulation only
(D) both (A) and (C)
20-The steady-state error of a feedback control
system with an acceleration input becomes finite in a
1. Type
0 system.
2. Type
I system.
3. Type
2 system.
4. Type
3 system.
(Ans: c)
21-A good control system has all the following
features except
1. Good
stability
2. Slow
response
3. Good
accuracy
4. Sufficient
power handling capacity
(Ans: b)
22-Which of the following is the best method for
determining the stability and transient response?
1. Root
locus
2. Bode
Plot
3. Nyquist
plot
4. None
of the above
(Ans: a)
23-Addition of zeros in transfer function causes
which of the following?
2. Lag-compensation
compensation
4. None
of the above
(Ans: b)
24-The control system design specification for a
chemical process is described as short settling time, improved damping and zero
steady state error. What control do we choose?
1. P
2. PI
3. ID
4. PID
(Ans: d)
25-Maxwell’s equations involve ________.
1. Charge
density
2. Current
density
3. Magnetic
intensity
4. All
of these
(Ans: d)
26-Which of the following is a low-gain antenna?
1. Dish
antenna on a space craft
2. Wi-Fi
antenna
3. Both
a. and b.
4. None
of the above
(Ans: b)
27-Gold and silver are
1. Dielectric
materials
2. Low
resistivity conducting materials
3. Magnetic
materials
4. Insulating
materials
(Ans: b)
28-Hall effect may be used for which of the
following
1. Determining
whether the semiconductor is p or n type
2. Determining
the carrier concentration
3. Calculating
the mobility
4. Al
of the above
(Ans:d )
29-The property due to which the resistance of
some metal or compound vanishes under certain conditions is known as
1. Semi
conductivity.
2. Magnetostriction.
3. Curie
point.
4. Super
conductivity.
(Ans: d)
30-A 32 to 1 multiplexer has the following
features.
1. 32
inputs, one output and 5 control signals
2. 32
outputs, one input and 5 control signals
3. 5
inputs, one control signal and 32 outputs
4. 5
inputs 32 control signals and one output
(Ans: a)
31-How many comparators would a 12-bit flash ADC
require?
1. 4095
2. 3095
3. 4000
4. 2512
(Ans: a)
32-In a sample and hold circuit the following
statement is false:
1. Sample
time is much smaller than hold time.
2. Aperture
time is the delay between the time that the pulse is applied to the switch
and the actual time the switch closes.
3. Acquisition
time is the tin-re it takes for the capacitor to charge from one voltage
to another voltage.
4. The
voltage across the hold capacitor changes by 50% during hold time.
(Ans: a)
33-The fastest switching logic family is
1. CMOS
2. TTL
3. DTL
4. ECL
(Ans: d)
34-A bridge rectifier provides 50mA current at
150V, the average current and PIV rating of each diode, respectively are:
1. 79mA,
l67V
2. 25mA,
236V
3. 12.5mA,
l67V
4. 25mA,
l20V
(Ans: b)
35-Compared to bipolar transistor, a JFET has
1. Lower
input impedance
2. Higher
voltage gain –
3. Higher
input impedance and high voltage gain
4. Higher
input impedance and low voltage gain
(Ans: d)
36-Input impedance of MOSSFET is
1. less
than of FET but more than BJT
2. More
than that of FET and BJT
3. more
than that of FET but less than BJT
4. less
than that of FET and BJT
(Ans: b)
37-A 3 x 8 decoder with two enable inputs is to
be used to address 8 blocks of memory. What will be the size of each memory
block when addressed from a sixteen bit bus with two MSBs used to enable the
decoder?
1. 2K
2. 4K
3. l6K
4. 64K
(Ans: c)
38-The decimal value for the BCD coded number
000100l0 is
1. 6
2. 10
3. 12
4. 18
(Ans: c)
39-In a DMA write operation the data is
transferred
1. From
I/O to memory.
2. From
memory to I/O.
3. from
memory to memory.
4. from
I/O to I/O.
(Ans: a)
40-The following magnet is used in large machines
to create magnetic flux
1. Permanent
magnet
2. Electro
magnet
3. Temporary
magnet
4. Any
of the above
(Ans: b)
41-The special device which converts AC into DC
and vice versa is known as
1. Armature
2. Slip
rings
3. Split
rings
4. Field
magnets
(Ans: c)
42-The following is (are) the part(s) of a field
magnet.
1. Yoke
2. Pole
cores
3. Pole
shoes
4. All
of the above
(Ans: d)
43-Function of _____ is to collect current from
the commutator and supply it to the external load.
1. Field
magnet
2. Armature
3. Brushes
4. Yoke
(Ans: c)
44-The brushes are ____ in shape.
1. Triangular
2. Rectangular
3. Cylindrical
4. Square
(Ans: b)
45-For larger machines
1. Ball
bearings are used at both driving and non driving ends.
2. Ball
bearings are used at driving end and roller bearings are used at non
driving end.
3. Roller
bearings are used at driving end and ball bearings are used at non driving
end.
4.  Roller
bearings are used at both driving and non driving ends.
(Ans: c)
46-The following is (are) keyed to the shaft
1. Armature
core
2. Commutator
3. Cooling
fan
4. All
of the above
(Ans: d)
47-Which of the following generators have two
field windings?
1. Series
wound generator
2. Shunt
wound generator
3. Compound
wound generator
4. All
of the above
(Ans: c)
48-A motor converts
1. Mechanical
energy into electrical energy
2. Chemical
energy into electrical energy
3. Electrical
energy into Mechanical energy
4. Electrical
energy into chemical energy
(Ans: c)
49-To produce dynamically induced emf, the
following is (are) necessary
1. A
magnetic field
2. A
conductor
3. Motion
of conductor with respect to the field
4. All
of the above
(Ans: d)
50-Which of the following is also called ‘motor
rule’?
1. Fleming’s
right hand rule
2. Fleming’s
left hand rule
3. All
of the above
(Ans: b)
51-Shaft torque equals to
1. Net
torque
2. Friction
torque
3. Net
torque + Friction torque + Torque lost
4. Net
torque – (Friction torque + Torque lost)
(Ans: d)
52-Iron or magnetic losses are also called
1. Core
losses
2. Field
losses
3. Copper
losses
4. Armature
losses
(Ans: a)
53-The mechanical losses are about _____ % of
1. 0
to 10
2. 10
to 20
3. 20
to 30
4. 30
to 40
(Ans: b)
54-The nucleus of an atom consists of
1. Protons
2. Neutrons
3. Protons
and Neutrons
4. Electrons
and Protons
(Ans: c)
55-A body contains electrons more than its normal
number has
1. +ve
charge
2. –ve
charge
3. No
charge
4. None
of the above
(Ans: b)
56-The SI unit for measurement of electric charge
is
1. volt
2. columb
3. ohm
(Ans: b)
57-One columb is approximately equal to
1. 624
x 10^12
2. 624
x 10^14
3. 624
x 10^16
4. 624
x 10^18
(Ans: c)
58-The ____ is responsible for the current to
flow in a closed circuit.
1. Electric
charge
2. Potential
difference
3. Resistance
4. All
of the above
(Ans: b)
electricity from the earth, when connected to it, is said to be
1. Zero
potential
2. –ve
potential
3. +ve
potential
4. None
of the above
(Ans: b)
60-Resistance of a wire is directly proportional
to its
1. Length
2. Diameter
3. Area
of cross section
4. All
of the above
(Ans: a)
61-Reciprocal of resistance is called
1. Resistivity
2. Conductance
3. Resonance
4. None
of the above
(Ans: b)
62-A coil consists of 8 turns of copper wire have
cross section area of 1mm^2. The resistance of the coil, when mean length per
turn is 0.02μΩm, is
1. 0.96
ohm
2. 0.48
ohm
3. 1.82
ohm
4. 1.44
ohm
(Ans: a)
63-The following is (are) the semiconductor(s)
1. Silicon
2. Germanium
3. Carbon
4. All
of the above
(Ans: d)
64-The resistance of pure metallic conductor
_____ with the _______ in temperature.
1. increases,
increase
2. increases,
decrease
3. remains
same, increase
4. remains
same, decrease
(Ans: a)
64-One kilowatt equals to _____ horse power.
1. 1.26
2. 1.36
3. 1.46
4. 1.56
(Ans: b)
66-The output of motor in watts when it takes a
power of 3kw and its efficiency is 75%, is
1. 2000
2. 2250
3. 2500
4. 2750
(Ans: b)
67-If three resistance (R1, R2 & R3) are
connected in series then
1. V
= IR1 + IR2 + IR3
2. V
= I/R1 + I/R2 + I/R3
3. I
= VR1 + VR2 + VR3
4. I
= V/R1 + V/R2 + V/R3
Where V=Potential difference, I=Current
(Ans: a)
68-When the resistances are connected in parallel
circuit then
1. branch
2. conductances
3. powers
4. All
of the above
(Ans: d)
69-In superconductivity the conductivity of a
material becomes
1. Zero
2. Finite
3. Infinite
4. None
of the above
(Ans:c)
70-In superconductivity, the electrical
resistance of material becomes
1. Zero
2. Infinite
3. Finite
4. All
of the above
(Ans:a)
71-The temperature at which conductivity of a
material becomes infinite is called
1. Critical
temperature
2. Absolute
temperature
3. Mean
temperature
4. Crystallization
temperature
(Ans:a)
72-In superconductors, the Fermi energy level is
1. Below
the ground state
2. Midway
between the ground state and first excited state
3. Above
first excited state
4. At
first excited state
(Ans:b)
73-The superconducting state is perfectly _____
in nature.
1. Diamagnetic
2. Paramagnetic
3. Ferromagnetic
4. Ferromagnetic
(Ans:a)
74-Which of the following are the properties of
superconductors?
1. They
are diamagnetic in nature
2. They
have zero resistivity
3. They
have infinite conductivity
4. All
of the above
(Ans:d)
75-The minimum amount of current passed through
the body of superconductor in order to destroy the superconductivity is called
1. Induced
current
2. Critical
current
3. Eddy
current
4. Hall
current
(Ans:b)
76-The energy required to break a cooper pair is
___ of the energy gap of superconductor.
1. One
half
2. Equal
to
3. Twice
4. Thrice
(Ans:b)
77-The binding energy for a cooper pair is
1. 10^-2
eV
2. 10^-4
eV
3. 10^-6
eV
4. 10^-8
eV
(Ans:b)
78-There are three important lengths which enter
the theory of superconductivity except
1. London
penetration length
2. Intrinsic
coherence length
3. Normal
electron mean free length
4. Mean
path length
(Ans:d)
79.The magnetic lines of force cannot penetrate
the body of a superconductor, a phenomenon is known as
1. Isotopic
effect
2. BCS
theory
3. Meissner
effect
4. London
theory
(Ans:c)
80-Which of the following conductor has highest
critical temperature?
1. Aluminium
2. Zinc
3. Molybdenium
4. Tin
(Ans:d)

1. Umar rashid