Explore topic-wise MCQs in Electrical Engineering Questions.

This section includes 99 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering Questions knowledge and support exam preparation. Choose a topic below to get started.

51.

At transition temperature the value of critical field is____________?
A. zero
B. negative real value
C. positive real value
D. complex value
Answer» B. negative real value
Discussion
52.

Copper, even though costly, finds use in the windings of electrical machines because_____________?
A. copper points offer low contact resistance
B. copper can be easily soldered and welded
C. copper windings are less bulky and the machines become compact
D. all of the above
Answer» E.
Discussion
53.

Which of the following materials is used for making coils of standard resistances ?
A. Copper
B. Nichrome
C. Platinum
D. Manganin
Answer» E.
Discussion
54.

Which of the following is an advantage of stranded conductor over equivalent single conductor ?
A. Less liability to kink
B. Greater flexibility
C. Less liability to break
D. All of the above
Answer» E.
Discussion
55.

is the property of absorbing moisture from atmosphere_____________?
A. Solubility
B. Viscosity
C. Porosity
D. Hygroscopicity
Answer» E.
Discussion
56.

Substances whose specific resistance abruptly decreases at very low temperature are called___________?
A. insulators
B. conductors
C. semiconductors
D. superconductors
Answer» E.
Discussion
57.

Due to which of the following factors the brush wear rate is altered ?
A. Speed of the machine
B. Contact pressure
C. Surface conditions of brush and commutator
D. Excessive sparking
E. All of the above
Answer» F.
Discussion
58.

The conduction of electricity, in semiconductors, takes place due to movement of______________?
A. positive ions only
B. negative ions only
C. positive and negative ions
D. electrons and holes
Answer» E.
Discussion
59.

Carbon rods are used in wet and dry cells because_____________?
A. carbon rod serves as conductor
B. carbon can resist the attack of battery acid
C. both (A) and (B)
D. either (A) or (B)
Answer» D. either (A) or (B)
Discussion
60.

Carbon resistors are used extensively because they are____________?
A. easy to make
B. compact
C. inexpensive
D. all of the above reasons
Answer» E.
Discussion
61.

Thermocouples are mainly used for the measurement of_____________?
A. temperature
B. resistance
C. eddy currents
D. coupling co-efficient
Answer» B. resistance
Discussion
62.

Steel wire is used as____________?
A. overhead telephone wire
B. earth wire
C. core wire of ACSR
D. all of the above
Answer» E.
Discussion
63.

Which of the following high resistance materials has the highest operating temperature ?
A. Kanthal
B. Manganin
C. Nichrome
D. Eureka
Answer» B. Manganin
Discussion
64.

Carbon bearings are used under which of the following conditions ?
A. Where lubrication is difficult or im-possible
B. Where corrosive chemical action exists
C. Where high temperature exists
D. All of the above
Answer» E.
Discussion
65.

Platinum is used in_____________?
A. electrical contacts
B. thermocouple
C. heating element in high temperature furnace
D. grids of special purpose vacuum tubes
E. all of the above
Answer» F.
Discussion
66.

In a crystal, an atom vibrates at a frequency determined by_______________?
A. the heat content of the crystal
B. the temperature of the crystal
C. the stiffness of the bonds it makes with neighbors
Answer» D.
Discussion
67.

Which of the following materials is preferred for transmitting electrical energy over long distance ?
A. Copper
B. Aluminium
C. Steel reinforced copper
D. Steel reinforced aluminium
Answer» E.
Discussion
68.

The superconductivity is due to____________?
A. the crystal structure having no atomic vibration at 0°K
B. all electrons interact in the super-conducting state
C. the electrons jump into nucleus at 0°K
D. none of the above
Answer» B. all electrons interact in the super-conducting state
Discussion
69.

Superconductors are becoming popular for use in________________?
A. generating very strong magnetic field
B. manufacture of bubble memories
C. generating electrostatic field
D. generating regions free from magnetic field
Answer» B. manufacture of bubble memories
Discussion
70.

A highly conductive material must have___________?
A. highest conductivity
B. lowest temperature co-efficient
C. good mechanical strength
D. good corrosion resistance
E. all of the above
Answer» F.
Discussion
71.

In a superconductor the value of critical density depends upon______________?
A. magnetic field strength
B. temperature
C. either (A) or (B)
D. both (A) and (B)
Answer» E.
Discussion
72.

Non-linear resistors______________?
A. produce harmonic distortion
B. follows Ohm’s law at low temperatures only
C. result in non-uniform heating
D. none of the above
Answer» B. follows Ohm’s law at low temperatures only
Discussion
73.

The conductivity of a conductor can be increased by_______________?
A. decreasing its temperature
B. increasing its temperature
C. decreasing its vibration
D. increasing its vibration
Answer» B. increasing its temperature
Discussion
74.

A carbon resistor contains_____________?
A. carbon crystals
B. solid carbon granules
C. pulverized coal
D. finely divided carbon black
Answer» E.
Discussion
75.

Total number of crystal systems is____________?
A. 2
B. 4
C. 7
D. 12
Answer» D. 12
Discussion
76.

In graphite, bonding is____________?
A. covalent
B. metallic
C. Vander Waals
D. Vander Waals and covalent
Answer» E.
Discussion
77.

Which of the following is a semiconductor material ?
A. Phosphorous
B. Rubber
C. Silicon
D. Aluminium
Answer» D. Aluminium
Discussion
78.

The conductivity of a metal is determined by____________?
A. the electronic concentration and the mobility of the free electrons
B. the number of valence electrons per atom
C. either (A) or (B)
D. none of the above
Answer» B. the number of valence electrons per atom
Discussion
79.

The structure sensitive property of a super conductor is______________?
A. critical magnetic field
B. transition temperature
C. critical current density
D. none of the above
Answer» D. none of the above
Discussion
80.

The resistivity of a metal is a function of temperature because_____________?
A. the amplitude of vibration of the atoms varies with temperature
B. the electron density varies with temperature
C. the electron gas density varies with temperature
Answer» B. the electron density varies with temperature
Discussion
81.

Due to which of the following reasons aluminium does not corrode in atmosphere ?
A. Aluminium is a noble metal
B. Atmospheric oxygen can only diffuse very slowly through the oxide layer which is formed on the surface of aluminium
C. No reaction with oxygen occurs ft Any of the above
Answer» C. No reaction with oxygen occurs ft Any of the above
Discussion
82.

The conductivity of an extrinsic semiconductor with temperature________________?
A. decreases
B. increases
C. remains constant
Answer» D.
Discussion
83.

The current due to electron flow in conduction band is the hole current in valence band?
A. equal to
B. less than
C. greater than
D. any of the above
Answer» D. any of the above
Discussion
84.

The number of atoms per unit cell in B.C.C. structure is_____________?
A. 1
B. 2
C. 4
D. 8
Answer» C. 4
Discussion
85.

is an element used in semiconductors whose atoms have three valence electrons?
A. An acceptor
B. A donor
C. Germanium
D. Silicon
Answer» B. A donor
Discussion
86.

The minority carrier concentration is largely a function of_____________?
A. forward biasing voltage
B. reverse biasing voltage
C. temperature
D. the amount of doping
Answer» D. the amount of doping
Discussion
87.

Which of the following material is not a semiconductor ?
A. Silica
B. Germanium
C. Selenium
D. Gallium-arsenide
Answer» B. Germanium
Discussion
88.

For germanium the forbidden energy gap is_______________?
A. 0.15 eV
B. 0.25 eV
C. 0.5eV
D. 0.7eV
Answer» E.
Discussion
89.

highest conductivity_____________?
A. lowest temperature co-efficient
B. good mechanical strength
C. good corrosion resistance
D. easy solderable and drawable quality
E. all of the above
Answer» F.
Discussion
90.

High resistivity materials are used in_____________?
A. precision instruments
B. heating elements
C. motor starters
D. incandescent lamps
E. all of the above
Answer» F.
Discussion
91.

Superconductivity is observed for____________?
A. infrared frequencies
B. d.c. and low frequency
C. a.c. and high frequency
D. frequencies having no effect
E. none of the above
Answer» C. a.c. and high frequency
Discussion
92.

The carbon percentage is least in__________________?
A. low carbon steel
B. wrought iron
C. cast iron
D. malleable iron
Answer» C. cast iron
Discussion
93.

Which of the following materials is the best conductor of electricity ?
A. Tungsten
B. Aluminium
C. Copper
D. Carbon
Answer» D. Carbon
Discussion
94.

The value of critical field below the transition temperature will_______________?
A. increase
B. decrease
C. remain unchanged
D. any of the above
Answer» B. decrease
Discussion
95.

The transition temperature of mercury is____________?
A. 18.0°K
B. 9.22°K
C. 4.12°K
D. 1.14’K
Answer» D. 1.14’K
Discussion
96.

Due to which of the following reasons copper and aluminium are not used for heating elements ?
A. Both have great tendency for oxidation
B. Both have low melting point
C. Very large length of wires will be required
D. All of the above
Answer» E.
Discussion
97.

Effect of moisture on the insulating materials is to________________?
A. decrease dielectric constant
B. decrease dielectric strength
C. decrease insulation resistance
D. increase dielectric loss
E. all of the above
Answer» F.
Discussion
98.

_____________is viscoelastic?
A. Cast-iron
B. Graphite
C. Rubber
D. Glass
Answer» D. Glass
Discussion
99.

Surface resistance of an insulating material is reduced due to the______________?
A. smoky and dirty atmosphere
B. humidity in the atmosphere
C. both (A) and (b)
D. neither (A) nor (b)
Answer» D. neither (A) nor (b)
Discussion