Category: Electrical Engineering Multiple Choice Questions

CABLES Multiple Choice Questions :-

1. The insulating material for a cable should have
A. low cost
B. high dielectric strength
C. high mechanical strength
D. all of the above
Answer: D

2. Which of the following protects a cable against mechanical injury ?
A. Bedding
B. Sheath
C. Armouring
D. None of the above
Answer: C

3. Which of the following insulation is used in cables ?
A. Varnished cambric
B. Rubber
C. Paper
D. Any of the above
Answer: D

4. Empire tape is
A. varnished cambric
B. vulcanised rubber
C. impregnated paper
D. none of the above
Answer: A

5. The thickness of the layer of insulation on the conductor, in cables, depends upon
A. reactive power
B. power factor
C. voltage
D. current carrying capacity
Answer: C

6. The bedding on a cable consists of
A. hessian cloth
B. jute
C. any of the above
D. none of the above
Answer: C

7. The insulating material for cables should
A. be acid proof
B. be non-inflammable
C. be non-hygroscopic
D. have all above properties
Answer: D

8. In a cable immediately above metallic sheath _____ is provided.
A. earthing connection
B. bedding
C. armouring
D. none of the above
Answer: B

9. The current carrying capacity of cables in D.C. is more thanthat in A.C. mainly due to
A. absence of harmonics
B. non-existence of any stability limit
C. smaller dielectric loss
D. absence of ripples
(e) none of the above
Answer: C

10. In case of three core flexible cable the colour of the neutral is
A. blue
B. black
C. brown
D. none of the above
Answer: A

11. cables are used for 132 kV lines.
A. High tension
B. Super tension
C. Extra high tension
D. Extra super voltage
Answer: D

12. Conduit pipes are normally used to protect _____ cables.
A. unsheathed cables
B. armoured
C. PVC sheathed cables
D. all of the above
Answer: A

13. The minimum dielectric stress in a cable is at
A. armour
B. bedding
C. conductor surface
D. lead sheath
Answer: D

14. In single core cables armouring is not done to
A. avoid excessive sheath losses
B. make it flexible
C. either of the above
D. none of the above
Answer: A

15. Dielectric strength of rubber is around
A. 5 kV/mm
B. 15 kV/mm
C. 30 kV/mm
D. 200 kV/mm
Answer: C

16. Low tension cables are generally used up to
A. 200 V
B. 500 V
C. 700 V
D. 1000 V
Answer: D

17. In a cable, the maximum stress under operating conditions is at
A. insulation layer
B. sheath
C. armour
D. conductor surface
Answer: D

18. High tension cables are generally used up to
A. 11kV
B. 33kV
C. 66 kV
D. 132 kV
Answer: A

19. The surge resistance of cable is
A. 5 ohms
B. 20 ohms
C. 50 ohms
D. 100 ohms
Answer: C

20. PVC stands for
A. polyvinyl chloride
B. post varnish conductor
C. pressed and varnished cloth
D. positive voltage conductor
(e) none of the above
Answer: A

In the cables, the location of fault is usually found out by comparing
A. the resistance of the conductor
B. the inductance of conductors
C. the capacitances of insulated conductors
D. all above parameters
Answer: C

22. In capacitance grading of cables we use a ______ dielectric.
A. composite
B. porous
C. homogeneous
D. hygroscopic
Answer: A

23. Pressure cables are generally not used beyond
A. 11 kV
B. 33 kV
C. 66 kV
D. 132 kV
Answer: C

24. The material for armouring on cable is usually
A. steel tape
B. galvanised steel wire
C. any of the above
D. none of the above
Answer: C

25. Cables, generally used beyond 66 kV are
A. oil filled
B. S.L. type
C. belted
D. armoured
Answer: A

26. The relative permittivity of rubber is
A. between 2 and 3
B. between 5 and 6
C. between 8 and 10
D. between 12 and 14
Answer: A

27. Solid type cables are considered unreliable beyond 66 kV because
A. insulation may melt due to higher temperature
B. skin effect dominates on the conductor
C. of corona loss between conductor and sheath material
D. there is a danger of breakdown of insulation due to the presence of voids
Answer: D

28. If the length of a cable is doubled, its capacitance
A. becomes one-fourth
B. becomes one-half
C. becomes double
D. remains unchanged
Answer: C

29. In cables the charging current
A. lags the voltage by 90°
B. leads the voltage by 90°
C. lags the voltage by 180°
D. leads the voltage by 180°
Answer: B

30. A certain cable has an insulation of relative permittivity 4. If the insulation is replaced by one of relative permittivity 2, the capacitance of the cable will become
A. one half
(6) double
C. four times
D. none of the above
Answer: A

31. If a cable of homogeneous insulation has a maximum stress of 10 kV/mm, then the dielectric strength of insulation should be
A. 5 kV/mm
B. 10 kV/mm
A. 15 kV/mm
D. 30 kV/mm
Answer: B

32. In the cables, sheaths are used to
A. prevent the moisture from entering the cable
B. provide enough strength
(e) provide proper insulation
D. none of the above
Answer: A

33. The intersheaths in the cables are used to
A. minimize the stress
B. avoid the requirement of good insulation
C. provide proper stress distribution
D. none of the above
Answer: C

34. The electrostatic stress in underground cables is
A. same at the conductor and the sheath
B. minimum at the conductor and maximum at the sheath
C. maximum at the conductor and minimum at the sheath
D. zero at the conductor as well as on the sheath
(e) none of the above
Answer: C

35. The breakdown of insulation of the cable can be avoided economically by the use of
A. inter-sheaths
B. insulating materials with different dielectric constants
C. both A. and B.
D. none of the above
Answer: C

36. The insulation of the cable decreases with
A. the increase in length of the insulation
B. the decrease in the length of the insulation
C. either A. or B.
D. none of the above
Answer: A

37. A cable carrying alternating current has
A. hysteresis losses only
B. hysteresis and leakage losses only
C. hysteresis, leakage and copper losses only
D. hysteresis, leakage, copper and friction losses
Answer: B

38. In a cable the voltage stress is maximum at
A. sheath
(6) insulator
(e) surface of the conductor
D. core of the conductor
Answer: D

39. Capacitance grading of cable implies
A. use of dielectrics of different permeabilities
B. grading according to capacitance of cables per km length
C. cables using single dielectric in different concentrations
D. capacitance required to be introduced at different lengths to counter the effect of inductance
(e) none of the above
Answer: A

40. Underground cables are laid at sufficient depth
A. to minimise temperature stresses
B. to avoid being unearthed easily due to removal of soil
C. to minimise the effect of shocks and vibrations due to gassing vehicles, etc.
D. for all of the above reasons
Answer: C

41. The advantage of cables over overhead transmission lines is
A. easy maintenance
B. low cost
C. can be used in congested areas
D. can be used in high voltage circuits
Answer: C

42. The thickness of metallic shielding on cables is usually
A. 0.04 mm
B. 0.2 to 0.4 mm
(e) 3 to 5 mm
D. 40 to 60 mm
Answer: A

43. Cables for 220 kV lines are invariably
A. mica insulated
B. paper insulated
C. compressed oil or compressed gas insulated
D. rubber insulated
(e) none of the above
Answer: C

44. Is a cable is to be designed for use on 1000 kV, which insulation would you prefer ?
A. Polyvinyle chloride
B. Vulcanised rubber
C. Impregnated paper
D. Compressed SFe gas
(e) none of the above
Answer: D

45. If a power cable and a communication cable are to run parallel the minimum distance between the two, to avoid interference, should be
A. 2 cm
B. 10 cm
C. 50 cm
D. 400 cm
Answer: C

46. Copper as conductor for cables is used as
A. annealed
B. hardened and tempered
C. hard drawn
D. alloy with chromium
Answer: A

47. The insulating material should have
A. low permittivity
B. high resistivity
C. high dielectric strength
D. all of the above
Answer: D

48. The advantage of oil filled cables is
A. more perfect impregnation
B. smaller overall size
C. no ionisation, oxidation and formation of voids
D. all of the above
Answer: D

49. The disadvantage with paper as insulating material is
A. it is hygroscopic
(6) it has high capacitance
C. it is an organic material
D. none of the above
Answer: A

50. The breakdown voltage of a cable depends on
A. presence of moisture
B. working temperature
C. time of application of the voltage
D. all of the above
Answer: D

51. It is difficult to maintain oil filled cables.
A. Yes
B. No
Answer: A

51. In capacitance grading a homogeneous dielectric is used.
A. Yes
B. No
Answer: B

52. In congested areas where excavation is expensive and inconvenient ‘draw in system’ of laying of underground cables is often adopted.
A. Yes
B. No
Answer: A

53. Natural rubber is obtained from milky sap of tropical trees.
A. Yes
B. No
Answer: A

54. Rubber is most commonly used insulation in cables.
A. Yes
B. No
Answer: A

59. Polyethylene has very poor dielectric and ageing properties.
A. Yes
B. No
Answer: B

60. The metallic sheath may be made of lead or lead alloy or of aluminium.
A. Yes
B. No
Answer: B

Cables MCQ questions with answers pdf download online exam test

Electrical Engineering Materials Objective Type Questions :-

1. The converse of hardness is known as
(a) malleability
(b) toughness
(c) softness
(d) none of the above
Ans: c

2. On which of the following factors does the resistivity of a material depend ?
(a) Resistance of the conductor
(b) Area of the conductor section
(c) Length of the conductor
(d) All of the above
Ans: d

3. is a negatively charged particle present in an atom.
(a) Proton
(b) Neutron
(c) Electron
(d) None of the above
Ans: c

4. The formula ____ determines the number of electrons that can be accommodated in any level.
(a) 2n2
(6) 4n2
(c) 2n3
(d) 4ns
Ans: a

5. The tiny block formed by the arrangement of a small group of atoms is called the
(a) unit cell
(b) space lattice
(c) either (a) or (b)
(d) none of the above
Ans: a

6. The co-ordination number of a simple cubic structure is
(a) 2
(b) 4
(c) 6
(d) 8
Ans: c

7. The covalent bond is formed by
(a) transfer of electrons between atoms
(b) sharing of electrons between atoms
(e) sharing of variable number of electrons by a variable number of atoms
(d) none of the above
Ans: b

8. A perfect conductor has
(a) zero conductivity
(b) unity conductivity
(c) infinite conductivity
(d) none of the above
Ans: c

9. The metal having the lowest temperature coefficient of resistance is
(a) gold
(b) copper
(c) aluminium
(d) kanthal
Ans: a

10. Commonly used conducting materials are
(a) copper
(b) aluminium
(c) both (a) and (b)
(d) copper and silver
(e) platinum and gold
Ans: c

11. 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
Ans: d

12. The kinetic energy of a bounded electron is
(a) less than that of unbounded electron
(6) greater than that of unbounded electron
(c) equal to that of unbounded electron
(d) infinite
(e) none of the above
Ans: a

13. A highly conductive material must have
(a) highest conductivity
(b) lowest temperature co-efficient
(c) good mechanical strength
(d) good corrosion resistance
(e) easy solderable and drawable quality
(f) all of the above
Ans: f

14. 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
Ans: a

15. 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
Ans: b

16. 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
Ans: a

17. The value of critical field below the transition temperature will
(a) increase
(b) decrease
(c) remain unchanged
(d) any of the above
Ans: a

18. 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)
Ans: d

19. 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
Ans: a

20. High resistivity materials are used in
(a) precision instruments
(6) heating elements
(c) motor starters
(d) incandescent lamps
(e) all of the above
Ans: e

21. Mercury as an electric contact material is
(a) a liquid
(b) a metal
(c) a metal liquid
(d) a gas
Ans: c

22. An H.R.C. fuse is
(a) a ceramic body having metal and caps
(b) a wire of platinum
(c) a heavy cross-section of copper or aluminium
(d) a ceramic tube having carbon rod inside it
Ans: a

23. Which of the following resistive materials has the lowest temperature co-efficient of resistance ?
(a) Nichrome
(b) Constantan
(c) Kanthal
(d) Molybdenum
Ans: a

24. The coils of D.C. motor starter are wound with wire of
(a) copper
(b) kanthal
(c) manganin
(d) nichrome
Ans: c

25. The conductors have transport phenomena of electrons due to
(a) electric field
(b) magnetic field
(c) electromagnetic field
(d) none of the above
Ans: a

26. The transition temperature of mercury is
(a) 18.0°K
(6) 9.22°K
(c) 4.12°K
(d) 1.14’K
Ans: c

27. By increasing impurity content in the metal alloy the residual resistivity always
(a) decreases
(b) increases
(c) remains constant
(d) becomes temperature independent
Ans: b

28. 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
Ans: c

29. At transition temperature the value of critical field is
(a) zero
(6) negative real value
(c) positive real value
(d) complex value
Ans: a

30. Which of the following variety of copper has the best conductivity ?
(a) Induction hardened copper
(b) Hard drawn copper
(c) Pure annealed copper
(d) Copper containing traces of silicon
Ans: c

31. Constantan contains
(a) silver and tin
(b) copper and tungsten
(c) tungsten and silver
(d) copper and nickel
Ans: d

32. Which of the following is the poorest conductor of electricity ?
(a) Carbon
(b) Steel
(c) Silver
(d) Aluminium
Ans: a

33 ______ has zero temperature co-efficient of resistance.
(a) Aluminium
(b) Carbon
(c) Porcelain
(d) Manganin
Ans: d

34. Piezoelectric materials serve as a source of _____ .
(a) resonant waves
(b) musical waves
(c) microwaves
(d) ultrasonic waves
Ans: d

35. In thermocouples which of the following pairs is commonly used ?
(a) Copper-constantan
(b) Aluminium-tin
(c) Silver-German silver
(d) Iron-steel
Ans: a

36. is viscoelastic.
(a) Cast-iron
(6) Graphite
(c) Rubber
(d) Glass
Ans: c

37. Carbon electrodes are not used in
(a) GLS lamps
(b) electric arc furnace
(c) dry cells
(d) cinema projectors
Ans: a

38. Solder is an alloy of
(a) copper and aluminium
(b) tin and lead
(c) nickel, copper and zinc
(d) silver, copper and lead
Ans: b

39 ______ is most commonly used for making magnetic recording tape
(a) Silver nitrate
(b) Ferric oxide
(c) Small particles of iron
(d) Silicon-iron
Ans: b

40. Overhead telephone wires are made of
(a) aluminium
(b) steel
(c) ACSR conductors
(d) copper
Ans: b

41. ______ is an example of piezoelectric material.
(a) Glass
(b) Quartz
(c) Corrundum
(d) Neoprene
Ans: b

42. _____ is the main constituent of glass
(a) Fe203
(b) Si02
(c) AI2O3
(d) B2O3
Ans: b

43. A good electric contact material should have all of the following properties except
(a) high resistivity
(b) high resistance to corrosion
(c) good thermal conductivity
(d) high melting point
Ans: a

44. Most of the common metals have _____ structure.
(a) linear
(b) hexagonal
(c) orthorhombic
(d) cubic
Ans: d

45. Which of the following affect greatly the resistivity of electrical conductors ?
(a) Composition
(b) Pressure
(c) Size
(d) Temperature
Ans: a

46. Thermonic emission occurs in
(a) vacuum tubes
(b) copper conductors
(c) ferrite cores
(d) transistors
Ans: a

47. _____ is a hard solder.
(a) Tin-lead
(6) Tin-silver-lead
(c) Copper-zinc
(d) None of the above
Ans: c

48. Addition of 0.3 to 4.5% silicon to iron _____ the electrical resistivity of iron.
(a) increases
(b) decreases
(c) does not change
Ans: a

49. Super conductivity can be destroyed by
(a) adding impurities
(b) reducing temperatures
(c) application of magnetic field
(d) any of the above
Ans: c

50. 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
Ans: a

51. A carbon resistor contains
(a) carbon crystals
(b) solid carbon granules
(c) pulverized coal
(d) finely divided carbon black.
Ans: d

52. Which of the following materials does not have covalent bonds ?
(a) Organic polymers
(b) Silicon
(c) Metals
Ans: c

53. In graphite, bonding is
(a) covalent
(b) metallic
(c) Vander Waals
(d) Vander Waals and covalent
Ans: d

54. Total number of crystal systems is
(a) 2
(b) 4
(c) 7
(d) 12
Ans: c

55. The number of atoms per unit cell in B.C.C. structure is
(a) 1
(b) 2
(c) 4
(d) 8
Ans: b

56. The conductivity of a metal is determined by
(a) the electronic concentration and the mobility of the free electrons
(6) the number of valence electrons per atom
(c) either (a) or (b)
(d) none of the above
Ans: a

57. 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
Ans: a

58. 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
Ans: c

59. 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
Ans: b

60. The impurity atoms is semiconductors
(a) inject more charge carriers
(6) reduce the energy gap
(c) increase the kinetic energy of valence electrons
(d) all of the above
Ans: b

61. Which of the following material is not a semiconductor ?
(a) Silica
(b) Germanium
(c) Selenium
(d) Gallium-arsenide
Ans: a

62. Carbon resistors are used extensively because they are
(a) easy to make
(b) compact
(c) inexpensive
(d) all of the above reasons
Ans: d

63. 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)
Ans: c

64. 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
Ans: e

65. Which of the following are non-conductors of electricity?
(a) Non-metal solids except carbon
(b) Air and most other gases
(c) Pure water and liquids in general except mercury
(d) All of the above
Ans: d

66. 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
Ans: d

67. Which of the following high resistance materials has the highest operating temperature ?
(a) Kanthal
(b) Manganin
(c) Nichrome
(d) Eureka
Ans: a

68. Steel wire is used as
(a) overhead telephone wire
(b) earth wire
(c) core wire of ACSR
(d) all of the above
Ans: d

69. Low resistivity materials are used in
(a) transformer, motor and generator windings
(b) transmission and distribution lines
(c) house wiring
(d) all above applications
Ans: d

70. 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
Ans: e

71. 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
Ans: d

72. 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
Ans: d

73. 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
(e) copper windings are less bulky and the machines become compact
(d) all of the above
Ans: d

74. Which of the following materials is used for making coils of standard resistances ?
(a) Copper
(b) Nichrome
(c) Platinum
(d) Manganin
Ans: d

75. Substances whose specific resistance abruptly decreases at very low temperature are called
(a) insulators
(b) conductors
(c) semiconductors
(d) superconductors
Ans: d

76. Which of the following materials is the best conductor of electricity ?
(a) Tungsten
(b) Aluminium
(c) Copper
(d) Carbon
Ans: c

77. is the property of absorbing moisture from atmosphere.
(a) Solubility
(b) Viscosity
(c) Porosity
(d) Hygroscopicity
Ans: d

78. Thermocouples are mainly used for the measurement of
(a) temperature
(b) resistance
(c) eddy currents
(d) coupling co-efficient
Ans: a

79. Due to which of the following fact, in India, aluminium is replacing copper ?
(a) Aluminium is more ductile and malleable than copper
(6) Aluminium is available in plenty, cheaper and lighter than copper
(c) Aluminium has lower resistivity than that of copper
(d) Aluminium has less temperature co-efficient than copper
Ans: b

80. 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
Ans: d

81. Which of the following is a semiconductor material ?
(a) Phosphorous
(b) Rubber
(c) Silicon
(d) Aluminium
Ans: c

82. Selenium is _____ semiconductor.
(a) extrnisic
(b) intmisic
(c) N-type
(d) P-type
Ans: b

83. ________ has the best damping properties.
(a) Diamond
(b) High speed steel
(c) Mild steel
(d) Cast iron
Ans: d

84. The photo-electric effect occurs only when the incident light has more than a certain critical
(a) intensity
(b) speed
(c) frequency
(d) wave length
Ans: c

85. If the resistance of a conductor does not vary in accordance with Ohm’s law it is known as
(a) non-linear conductor
(b) reverse conductor
(c) bad-conductor
(d) non-conductor
Ans: a

86. Spark plug makes use of which of the following materials for insulation ?
(a) Porcelain
(b) Slate
(c) Asbestos
(d) Glass
Ans: a

87. The forbidden gap in an insulator is
(a) large
(b) small
(c) nil
(d) any of the above
Ans: a

88. Which of the following factors affect resistivity of metals ?
(a) Age hardening
(b) Alloying
(c) Temperature
(d) Cold work
(e) All of the above
Ans: e

89. 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
Ans: e

90. 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)
Ans: c

91. Superconducting metal in super conducting state has relative permeability of
(a) zero
(b) one
(c) negative
(d) more than one
Ans: a

92. In conductors conduction of electricity takes place due to movement of
(a) electrons only
(b) positive ions only
(c) negative ions only
(d) positive and negative ions
(e) none of the above
Ans: a

93. The carbon percentage is least in
(a) low carbon steel
(b) wrought iron
(c) cast iron
(d) malleable iron
Ans: b

94. For a particular material the Hall coefficient was found to be zero. The material is
(a) insulator
(6) metal
(c) intrinsic semiconductor
(d) none of the above
Ans: b

95. The conductivity of an extrinsic semiconductor with temperature
(a) decreases
(b) increases
(c) remains constant
Ans: c

96. 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
Ans: c

97. For a hole which of the following statements is incorrect ?
(a) Holes can exist in certain semiconductors only
(b) Holes can exist in any material including conductors
(c) Holes may constitute an electric current
(d) Holes can be considered as a net positive charge
Ans: b

98. is an element used in semiconductors whose atoms have three valence electrons.
(a) An acceptor
(b) A donor
(c) Germanium
(d) Silicon
Ans: a

99. The minority carrier concentration is largely a function of
(a) forward biasing voltage
(b) reverse biasing voltage
(c) temperature
(d) the amount of doping
Ans: c

100. For germanium the forbidden energy gap is
(a) 0.15 eV
(b) 0.25 eV
(C) 0.5eV
(d) 0.7eV
Ans: d