electrical engineering materials MCQs – Page 4

Practise focused electrical engineering materials questions with marked answers for exam preparation and subject revision.

electrical engineering materials Mcqs
61. Thermonic emission occurs in______________?
comments icon0
A. vacuum tubes

B. transistors

C. ferrite cores

D. copper conductors

62. By increasing impurity content in the metal alloy the residual resistivity always_____________?
comments icon0

A. decreases

B. remains constant

C. increases

D. becomes temperature independent

63. The converse of hardness is known as______________?
comments icon0
A. softness

B. toughness

C. none of the above

D. malleability

64. The kinetic energy of a bounded electron is______________?
comments icon0

A. infinite

B. none of the above

C. greater than that of unbounded electron

D. less than that of unbounded electron

E. equal to that of unbounded electron

65. Non-linear resistors______________?
comments icon0
A. produce harmonic distortion

B. none of the above

C. follows Ohms law at low temperatures only

D. result in non-uniform heating

66. The photo-electric effect occurs only when the incident light has more than a certain critical____________?
comments icon0

A. speed

B. wave length

C. frequency

D. intensity

67. The resistivity of a metal is a function of temperature because_____________?
comments icon0

A. the electron density varies with temperature

B. the amplitude of vibration of the atoms varies with temperature

C. the electron gas density varies with temperature

68. In conductors conduction of electricity takes place due to movement of_______________?
comments icon0

A. negative ions only

B. electrons only

C. none of the above

D. positive and negative ions

E. positive ions only

69. Piezoelectric materials serve as a source of ____________ ?
comments icon0

A. resonant waves

B. ultrasonic waves

C. musical waves

D. microwaves

70. Which of the following high resistance materials has the highest operating temperature ?
comments icon0
A. Kanthal

B. Eureka

C. Nichrome

D. Manganin

71. The transition temperature of mercury is____________?
comments icon0
A. 4.12K

B. 9.22K

C. 1.14K

D. 18.0K

72. Overhead telephone wires are made of_____________?
comments icon0
A. steel

B. ACSR conductors

C. aluminium

D. copper

73. Which of the following variety of copper has the best conductivity ?
comments icon0
A. Pure annealed copper

B. Hard drawn copper

C. Induction hardened copper

D. Copper containing traces of silicon

74. Constantan contains_______________?
comments icon0
A. copper and nickel

B. tungsten and silver

C. copper and tungsten

D. silver and tin

75. The tiny block formed by the arrangement of a small group of atoms is called the____________?
comments icon0

A. either A. or (b)

B. none of the above

C. space lattice

D. unit cell
76. The conductivity of an extrinsic semiconductor with temperature________________?
comments icon0

A. increases

B. decreases

C. remains constant
77. The structure sensitive property of a super conductor is______________?
comments icon0

A. transition temperature

B. critical current density

C. none of the above

D. critical magnetic field

78. The coils of D.C. motor starter are wound with wire of_______________?
comments icon0

A. kanthal

B. copper

C. nichrome

D. manganin
79. Which of the following factors affect resistivity of metals ?
comments icon0

A. Age hardening

B. Alloying

C. All of the above

D. Temperature

E. Cold work

80. In a superconductor the value of critical density depends upon______________?
comments icon0

A. magnetic field strength

B. temperature

C. either (A) or (B)

D. both (A) and (B)