Both natural forces and deliberate measures can close the inflationary gap created by excess expenditures, but the latter are considered more reliable and certain than the former.
The inflationary gap causes the prices to rise, but the price rise does nothing directly to eliminate the gap. However, there are a number of indirect effects of the price rise which tend to reduce the gap.
1.Keynes’ Effect:
When money supply is constant or rises in small proportions than prices, rate of interest will rise, tending to reduce the investment expenditure.
2.Wealth Effect:
Higher prices may reduce consumption expenditure by reducing real wealth held in the form of government money and government debt.
3.Balance-of-Trade Effect:
Higher prices will lead to encourage imports and reduce exports.
4. Fiscal Effect:
(i) If tax collections rise faster than prices, this will shift the consumption downward by reducing the real disposable income.
(ii) Transfer payments fixed in money terms become less significant in real terms, thus reducing consumption expenditure.
(iii) Real government purchase will also be reduced if budgets are fixed in money terms.
5.Price Expectation Effect:
If the current rise in prices is expected to be temporary and to be followed by later reduction in prices, consumer buying of durables and investment in plant and equipment may be delayed and inventories reduced, thus narrowing the inflationary gap.
6.Redistribution Effect:
If money wage rates are fixed (or wage- adjustment gap exists), higher prices will go entirely to profits. Assuming the marginal propensity to consume of the profit earners less than that of the wage earners, a redistribution of income towards profits will tend to reduce aggregate demand and to narrow the inflationary gap.
7.Money illusion Effect:
If some spenders suffer from money illusion and at least a part of their expenditure is fixed in money terms, inflation will reduce the real value of such expenditure and close the inflationary gap.
Rather than waiting for the natural forces to close the inflationary gap, fiscal policy can be used to reduce government expenditure and to increase taxes, thus to reduce the total expenditure in the economy.
In other words, government should incur a budget surplus. Monetary policy can also be directed towards decreasing the money supply. The Keynesians, however, doubt efficacy of monetary policy to deal with both inflationary and deflationary situations.
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
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
Inflation is a dynamic phenomenon, but the analysis of inflationary gap, being static in nature, has the following limitations.
1.Time Lags:
There are time lags between the receipt of income and its expenditure and between the adjustment of wages and prices. But for these time lags, inflation during and after war periods would have been much more serious and disastrous.
Larger these lags, milder will be the effect of inflation and vice versa. As Keynes remarked in his How to Pay for the War, “It is these time-lags and other impediments that come to our rescue. Wars do not last for ever.”
2.Current Flows:
Inflationary gap deals with current flows of income, spending, consumption, investment, saving, etc. But, inflation being a dynamic phenomenon, the increase in price and the expectations of price rise do not affect the current output alone.
They also affect the output which has been previously produced and is still available in the market.
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
The monetarist theory of demand-pull inflation is based on the quantity theory of money. According to the quantity theory of money, increases in the supply of money, given its velocity, lead to increases in the total money expenditure.
Assuming full employment, the increased demand will pull prices higher. Thus, according to the monetarists, inflation is a monetary phenomenon.
The monetarist theory can be studied with respect to static and dynamic conditions:
(i) In a static economy, with a given level of output, according to the equation of exchange: MV = PT, increases in the supply of money (M) alone are responsible for increases in the price level (P), assuming the velocity of money (V) constant ; P increases in the same proportion as M increases. Thus, the rate of inflation is given by
P = M
That is, the rate of change of prices (P) is proportionate to the rate of change of money supply (M). Since M is a policy variable, the rate of inflation also becomes policy determined.
(ii) In a growing economy, real national income (Y) is increasing over time due to the operation of various growth factors. Again, in such an economy, the real demand for money will also be growing over time.
According to the Cambridge equation of the quantity theory of money (i.e., M = KPY), the rate of growth of real demand for money will be equal to the rate of growth of real national income because the income elasticity of demand for money is necessarily unity.
The growth rate of real demand for money tells us the rate at which new money can be absorbed in the economy at constant prices.
The excess increases in the stock of money will lead to increase in prices and will become inflationary. Thus, for a growing economy, the rate of inflation is given by P = M – Y
That is, the rate of increase in prices (P) is proportionate to the excess rate of increase in the supply of money (M – Y).
1. The main function of a fuse is to
(a) protect the line
(b) open the circuit
(c) protect the appliance
(d) prevent excessive currents
(e) none of the above
Ans: d
2. On which of the following routine tests are conducted ?
(a) Oil circuit breakers
(b) Air blast circuit breakers
(c) Minimum oil circuit breakers
(d) All of the above
Ans: d
3. SF6 gas
(a) is yellow in colour
(b) is lighter than air
(c) is nontoxic
(d) has pungent small
(e) none of the above
Ans: c
4. The arcing contacts in a circuit breaker are made of
(a) copper tungsten alloy
(b) porcelain
(c) electrolytic copper
(d) aluminium alloy
Ans: a
5. Which of the following medium is employed for extinction of arc in air circuit breaker ?
(a) Water
(b) Oil
(c) Air
(d) SF6
Ans: c
6. With which of the following, a circuit breaker must be equipped for remote operation ?
(a) Inverse time trip
(b) Time-delay trip
(c) Shunt trip
(d) None of the above
(e) All of the above
Ans: c
7. Fault diverters are basically
(a) fuses
(b) relays
(c) fast switches
(d) circuit breakers
Ans: c
8. A thermal protection switch can protect against
(a) short-circuit
(b) temperature
(c) overload
(d) over voltage
Ans: c
9. Arc in a circuit behaves as
(a) a capackive reactance
(b) an inductive reactance
(c) a resistance increasing with voltage rise across the arc
(d) a resistance decreasing with voltage rise across the arc
Ans: d
10. Thermal circuit breaker has
(a) delayed trip action
(b) instantaneous trip action
(c) both of the above
(d) none of the above
Ans: a
SWITCHGEAR & PROTECTION Mcqs
11. Relays can be designed to respond to changes in
(a) resistance, reactance or impedance
(b) voltage and current
(c) light intensity
(d) temperature
(e) all above
Ans: e
12. Overload relays are of…… type.
(a) induction
(b) solid state
(c) thermal
(d) electromagnetic
(e) all above
Ans: e
13. Thermal overload relays are used to protect the motor against over current due to
(a) short-circuits
(b) heavy loads
(c) grounds
(d) all of the above
Ans: b
14. Magnetic circuit breaker has ______ trip action.
(a) delayed
(b) instantaneous
(c) both of the above
(d) none of the above
Ans: b
15. D.C. shunt relays are made of
(a) few turns of thin wire
(b) few turns of thick wire
(c) many turns of thin wire
(d) many turns of thick wire
Ans: c
16. The relay operating speed depends upon
(a) the spring tension
(b) the rate of flux built up
(c) armature core air gap
(d) all of the above
Ans: d
17. In order that current should flow without causing excessive heating or voltage drop, the relay contacts should
(a) have low contact resistance
(b) be clean and smooth
(c) be of sufficient size and proper shape
(d) have all above properties
Ans: d
18. Circuit breakers usually operate under
(a) transient state of short-circuit current
(b) sub-transient state of short-circuit current
(c) steady state of short-circuit current
(d) after D.C. component has ceased
Ans: a
19. Circuit breakers are essentially
(a) current carrying contacts called electrodes
(b) arc extinguishers
(c) circuits to break the system
(d) transformers to isolate the two systems
(e) any of the above
Ans: a
20. The current zero interruption, in oil and air blast circuit breakers, is achieved by
(a) lengthening of the gap
(b) cooling and blast effect
(c) both (a) and (b)
(d) deionizing the oil with forced air
(e) none of the above
Ans: c
21. Air blast circuit breaker is used for
(a) over currents
(b) short duty
(c) intermittant duty
(d) repeated duty
Ans: d
22. An efficient and a well designed protective relaying should have
(a) good selectivity and reliability
(b) economy and simplicity
(c) high speed and selectivity
(d) all of the above
Ans: d
23. Burden of a protective relay is the power
(a) required to operate the circuit breaker
(b) absorbed by the circuit of relay
(c) developed by the relay circuit
(d) none of the above
Ans: b
24. Directional relays are based on flow of
(a) power
(b) current
(c) voltage wave
(d) all of the above
Ans: a
25. A differential relay measures the vector difference between
(a) two currents
(b) two voltages
(c) two or more similar electrical quantities
(d) none of the above
Ans: c
26. A transmission line is protected by
(a) inrush protection
(b) distance protection
(c) time graded and current graded over current protection
(d) both (b) and (c)
(e) none of the above
Ans: d
27. Large internal faults are protected by
(a) merz price percentage differential protection
(b) mho and ohm relays
(c) horn gaps and temperature relays
(d) earth fault and positive sequence relays
Ans: a
28. When a transmission line is energized, the wave that propagates on it is
(a) current wave only
(b) voltage wave only
(c) both (a) and (b)
(d) power factor wave only
Ans: c
29. Protective relays are devices that detect abnormal conditions in electrical circuits by measuring
(a) current during abnormal condition
(b) voltage during abnormal condition
(c) constantly the electrical quantities which differ during normal and abnormal conditions
(d) none of the above
Ans: c
30. The voltage appearing across the contacts after opening of the circuit breaker is called______voltage.
(a) recovery
(b) surge
(c) operating
(d) arc
(e) none of the above
Ans: a
31. Ionization in circuit breaker is facilitated by
(a) high temperature
(b) increase of mean free path
(c) increasing field strength
(d) all of the above
Ans: d
32. In a circuit breaker the basic problem is to
(a) maintain the arc
(b) extinguish the arc
(c) transmit large power
(d) emit the ionizing electrons
Ans: c
33. Overheating of relay contacts or contact born out is due to
(a) slow making and breaking of load circuit contacts
(b) foreign matter on the contact surface
(c) too low contact pressure
(d) all of the above
Ans: d
34. Interruption of large currents by relay requires
(a) arc suppressing blow out coils
(b) wide separation of the opened contacts
(c) high speed opening of contacts
(d) all of the above
Ans: d
35. Shunt capacitance is neglected while considering
(a) short transmission line
(b) medium transmission line
(c) long transmission line
(d) medium and long transmission lines
Ans: a
36. The arc voltage produced in A.C. circuit breaker is always
(a) in phase with the arc current
(b) lagging the arc current by 90″
(c) leading the arc current by 90°
(d) none of the above
Ans: a
37. The time of closing the cycle, in modern circuit breakers is
(a) 0.003 sec
(b) 0.001 sec
(c) 0.01 sec
(d) 0.10 sec
(e) none of the above
Ans: a
38. Insulation resistance of high voltage circuit breakers is more than
(a) 1 mega ohms
(b) 10 mega ohms
(c) 100 mega ohms
(d) 500 mega ohms
Ans: c
39. H.R.C. fuses provide best protection against
(a) overload
(b) reverse current
(c) open-circuits
(d) short-circuits
Ans: d
40. The ground wire should not be smaller than No ______ copper.
(a) 2
(b) 4
(c) 6
(d) 10
Ans: d
41. The delay fuses are used for the protection of ________ .
(a) motors
(b) power outlet circuits
(c) fluorescent lamps
(d) light circuits
Ans: a
42. Which of the following is the least expensive protection for overcurrent is low voltage system ?
(a) Rewireable fuse
(b) Isolator
(c) Oil circuit breaker
(d) Air break circuit breaker
(e) None of the above
Ans: a
43. Resistance grounding is used for voltage between
(a) 33kVto66kV
(b) HkVto33kV
(c) 3.3kVandllkV
(d) none of the above
Ans: c
44. The contacts of high voltage switches used in power system are submerged in oil. The main purpose of the oil is to
(a) lubricate the contacts
(b) insulate the contacts from switch body
(c) extinguish the arc
(d) all of the above
(e) none of the above
Ans: c
45. In Railway applications ______ circuit breaker is used.
(a) SFe
(b) bulk oil
(c) minimum oil
(d) air break
Ans:
46. To protect most of the electrical equipment handling low power, the types of relays used are
(a) thermocouple
(b) electronic and bimetallic
(c) both (a) and (b)
(d) none of the above
Ans: c
47. Wave trap is used to trap waves of
(a) power frequencies
(b) higher frequencies entering generator or transformer units
(c) either of the above
(d) none of the above
Ans: b
48. Ungrounded neutral transmission system is not recommended because of system
(a) insulation being overstressed due to over voltages
(b) insulation overstress may lead to failure and subsequent phase to phase faults
(c) being inadequately protected against ground fault
(d) all of the above
Ans: d
49. The reflection co-efficient at the open circuited end of a transmission line.
(a) zero
(b) infinity
(c) unity
(d) none of the above
Ans: c
50. For the protection of power station buildings against direct strokes the requirements are
(a) interception
(b) interception and conduction
(c) interception, conduction and dissipation
(d) interception, conduction, dissipation and reflection
(e) none of the above
Ans: c
51. The line insulation is the insulation level of the station equipment.
(a) less than
(b) same as
(c) more than
(d) proportional to
(e) not directly related with
Ans: e
52. The interaction between a transmission line and communication line is minimized by
(a) transposing transmission as well as communication lines
(b) increasing the height of the trans-mission line tower
(c) increasing the distance between the two lines
(d) all of the above
Ans: d
53. When a wave propagates on a transmission line, it suffers reflection several times at
(a) tapping
(b) load end
(c) sending end
(d) sending and other end
(e) all of the above
Ans: d
54. Which of the following statements is incorrect?
(a) Station batteries are used to operate relay only
(b) The lightning arresters are basically surge diverters
(c) An impedance relay has maximum fault current when fault occurs near the relay
(d) A high speed relay has an operation of 1 to 2 cycles
Ans: a
55. Discrimination between main and back up protection is provided by the use of relays which are
(a) fact
(b) sensitive
(c) slow
(d) none of the above
Ans: c
56. Induction cup relay is operated due to changes in
(a) current
(b) voltage
(c) impedance
(d) all of the above
Ans: d
57. A.C. network analyser is used to solve problems of
(a) load flow
(b) load flow and short-circuit
(c) load flow and stability
(d) load flow, short-circuit and stability
(e) none of the above
Ans: d
58. Which of the following statements is incorrect ?
(a) Lightning arrestors are used before the switchgear
(b) Shunt reactors are used as compensation reactors
(c) The peak short current is (1.8 xV2) times the A.C. component
(d) The MVA at fault is equal to base MVA divided by per unit equivalent fault reactance
Ans: a
59. Short-circuit currents are due to
(a) single phase to ground faults
(b) phase to phase faults
(c) two phase to ground faults
(d) three phase faults
(e) any of these
Ans: e
60. To reduce short circuit fault currents are used.
(a) reactors
(b) resistors
(c) capacitors
(d) none of the above
Ans: a
61. Bus coupler is very essential in arrangement
(a) single bus
(b) double bus, double breaker
(c) main and transfer bus
(d) all of the above
Ans: c
62. For cost and safety, the outdoor substations are installed for voltages above
(a) 11 kV
(b) 33 kV
(c) 60kV
(d) 110kV
Ans: b
63. The short circuit in any winding of the transformer is the result of
(a) mechanical vibration
(b) insulation failure
(c) loose connection
(d) impulse voltage
Ans: d
64. relays are used for phase faults on long line.
(a) Impedance
(b) Reactance
(c) Either of the above
(d) None of the above
Ans: a
65. For which of the following protection from negative sequence currents is provided ?
(a) Generators
(b) Motors
(c) Transmission line
(d) Transformers
Ans: a
66. relay is preferred for phase fault on short transmission line.
(a) Induction type
(b) Reactance
(c) Impedance
(d) None of the above
Ans: b
67. Distance relays are generally
(a) split-phase relays
(b) reactance relays
(c) impedance relays
(d) none of the above
Ans: d
68. For which of the following ratings of the transformer differential protection is recommended ?
(a) above 30 kVA.
(b) equal to and above 5 MVA
(c) equal to and above 25 MVA
(d) none of the above
Ans: b
69. A _______ is used to measure the stator % winding temperature of the generator.
(a) thermocouple
(b) pyrometer
(c) resistance thermometer
(d) thermometer
Ans: c
70. The under voltage relay can be used for
(a) generators
(b) busbars
(c) transformers
(d) motors
(e) all of the above
Ans: e
71. The relay with inverse time characteristic will operate within
(a) 1.5 sec
(b) 5 to 10 sec
(c) 5 to 20 sec
(d) 20 to 30 sec
(e) none of the above
Ans: b
72. The single phasing relays are used for the protection of
(a) single phase motors only
(b) two phase motors only
(c) two single phase motors running in parallel
(d) three phase motors
Ans: d
73. Which of the following devices will receive voltage surge first travelling on the transmission line ?
(a) Lightning arresters
(b) Relays
(c) Step-down transformer
(d) Switchgear
Ans: a
74. Which of the following parameter can be neglected for a short line ?
(a) Inductance
(b) Capacitance
(c) Resistance
(d) Reactance
Ans: b
75. Series reactors should have
(a) low resistance
(b) high resistance
(c) low impedance
(d) high impedance
Ans: a
76. Which of the following circuit breakers has high reliability and minimum maintenance ?
(a) Air blast circuit breakers
(b) Circuit breaker with SF6 gas
(c) Vacuum circuit breakers
(d) Oil circuit breakers
Ans: b
77. Arc in a circuit breaker is interrupted at
(a) zero current
(b) maximum current
(c) minimum voltage
(d) maximum voltage
Ans: a
78. transmission line has reflection coefficient as one.
(a) Open circuit
(b) Short-circuit
(e) Long
(d) None of the above
Ans: a
79. What will be the reflection co-efficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ?
(a) Zero
(b) Unity
(c) Infinity
(d) None of the above
Ans: a
80. The inverse definite mean time relays are used for over current and earth fault protection of transformer against
(a) heavy loads
(b) internal short-circuits
(c) external short-circuits
(d) all of the above
Ans: b
81. Over voltage protection is recommended for
(a) hydro-electric generators
(b) steam turbine generators
(c) gas turbine generators
(d) all of the above
(e) none of the above
Ans: d
82. Air blast circuit breakers for 400 kV power system are designed to operate in
(a) 100 microsecond
(b) 50 millisecond
(c) 0.5 sec
(d) 0.1 sec
Ans: b
83. Overfluxing protection is recommended for
(a) distribution transformer
(b) generator transformer of the power plant
(c) auto-transformer of the power plant
(d) station transformer of the power plant
Ans: b
84. Series capacitors are used to
(a) compensate for line inductive reactance
(b) compensate for line capacitive reactance
(c) improve line voltage
(d) none of the above
Ans: a
85. Admittance relay is _______ relay.
(a) impedance
(b) directional
(c) non-directional
(d) none of the above
Ans: b
86. The material used for fuse must have
(a) low melting point and high specific resistance
(b) low melting point and -low specific resistance
(c) high melting point and low specific resistance
(d) low melting point and any specific resistance
Ans: a
87. If the fault occurs near the impedance relay, the VII ratio will be
(a) constant for all distances
(b) lower than that of if fault occurs away from the relay
(c) higher than that of if fault occurs away from the relay
(d) none of the above
Ans: b
88. The torque produced in induction type relay (shaded pole structure) is
(a) inversely proportional to the current
(b) inversely proportional to the square of the current
(c) proportional to the current
(d) proportional to square of the current
Ans: b
89. The steady state stability of the power system can be increased by
(a) connecting lines in parallel
(b) connecting lines in series
(e) using machines of high impedance
(d) reducing the excitation of machines
(e) none of the above
Ans: a
90. The inductive interference between power and communication line can be minimized by
(a) transposition of the power line
(b) transposition of the communication line
(c) both (a) and (b)
(d) increasing the distance between the conductors
Ans: c
91. The power loss is an important factor for the design of
(a) transmission line
(b) motor
(c) generator
(d) feeder
Ans: a
92. A fuse is connected
(a) in series with circuit
(b) in parallel with circuit
(c) either in series or in parallel with circuit
(d) none of the above
Ans: a
93. H.R.C. fuse, as compared to a rewirable fuse, has
(a) no ageing effect
(b) high speed of operation
(c) high rupturing capacity
(d) all of the above
Ans: d
94. The fuse rating is expressed in terms of
(a) current
(b) voltage
(c) VAR
(d) kVA
Ans: a
95. The fuse blows off by
(a) burning
(b) arcing
(c) melting
(d) none of the above
Ans: c
96. On which of the following effects of electric current a fuse operates ?
(a) Photoelectric effect
(b) Electrostatic effect
(c) Heating effect
(d) Magnetic effect
Ans: c
97. An isolator is installed
(a) to operate the relay of circuit breaker
(b) as a substitute for circuit breaker
(c) always independent of the position of circuit breaker
(d) generally on both sides of a circuit breaker
Ans: d
98. A fuse in a motor circuit provides protection against
(a) overload
(b) short-circuit and overload
(c) open circuit, short-circuit and overload
(d) none of the above
Ans: b
99. Protection by fuses is generally not used beyond
(a) 20 A
(b) 50 A
(c) 100 A
(d) 200 A
Ans: c
100. A fuse is never inserted in
(a) neutral wire
(b) negative of D.C. circuit
(c) positive of D.C. circuit
(d) phase dine
Ans: a
101. Oil switches are employed for
(a) low currents circuits
(b) low voltages circuits
(c) high voltages and large currents circuits
(d) all circuits
Ans: c
102. A switchgear is device used for
(a) interrupting an electrical circuit
(b) switching an electrical circuit 111.
(c) switching and controlling an electrical circuit
(d) switching, controlling and protecting the electrical circuit and equipment
Ans: d
103. The fuse wire, in D.C. circuits, is inserted in
(a) negative circuit only
(b) positive circuit only
(c) both (a) and (b)
(d) either (a) or (b)
Ans: c
104. By which of the following methods major portion of the heat generated in a H.R.C. fuse is dissipated ?
(a) Radiation
(b) Convection
(c) Conduction
(d) All of the above
Ans: c
105. A short-circuit is identified by
(a) no current flow
(b) heavy current flow
(c) voltage drop
(d) voltage rise
Ans: b
106. The information to the circuit breaker under fault conditions is provided by
(a) relay
(b) rewirable fuse
(c) H.R.C. only
(d) all of the above
Ans: a
107. To limit short-circuit current in a power system are used.
(a) earth wires
(b) isolators
(c) H.R.C. fuses
(d) reactors
Ans: d
109. A balanced 3-phase system consists of
(a) zero sequence currents only
(b) positive sequence currents only
(c) negative and zero sequence currents
(d) zero, negative and positive sequence currents
Ans: b
110. In a single bus-bar system there will be complete shut down when
(a) fault occurs on the bus itself
(b) fault occurs on neutral line
(c) two or more faults occur simultaneously
(d) fault occurs with respect to earthing
Ans: a
SWITCHGEAR & PROTECTION Questions and Answers Pdf Download
