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1. Switchgear & Protection 1. Relay contacts are normally made up of: a) Silver contacts b) Copper contacts c) Aluminum contacts d) Lead contacts A 2. The most efficient torque-producing actuating structure for induction type relays is: a) Shaded pole structure b) Watt-hour meter structure c) Induction cup structure d) Single induction cup structure C 3. Impedance relays can be used for: a) Phase faults only b) Earth faults only c) Both earth and phase faults d) None of the above C 4. Sparking between the contacts can be reduced by inserting: a) A capacitor in parallel with the contacts b) A capacitor in series with the contacts c) A resistor in the line d) A reactor in the line A 5. The contact resistance is least affected by: a) Shape of the contact faces b) Ambient temperature c) Mechanical forces applied d) Amount of surface commutation B 6. The arc voltage produced in an ac circuit breaker is always:

a) In phase with the arc current b) Lagging the arc current by 90 deg c) Leading the arc current by 90 deg d) In phase opposition with the arc current A 7. Breaking capacity of the circuit breaker is usually expressed in: a) MVA b) MW c) Kilo-amperes d) kV A 8. Which of the following circuit breakers produce least arc energy: a) Plain oil b) Minimum oil c) Air blast d) Air break C 9. Arc chutes are used in: a) Oil circuit breaker b) Vacuum circuit breakers c) SF6 circuit breakers d) Air blast circuit breakers D 10. A thermal protection switch is used to provide protection against: a) Over load b) Temperature c) Short circuit d) Over voltage A

11. Mho relay have an R-X characteristics depicted by: a) A straight line passing through origin b) A straight line parallel to X-axis c) A straight line parallel to R-axis d) A circle passing through the origin D

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12. Any winding of a power transformer develops short circuit owing to: a) Loose connections b) Insulation failure c) Impulse voltage d) Mechanical vibration C 13. The relay used for the feeder protection is: a) Under-voltage relay b) Translay relay c) Thermal relay d) Buchholz relay B 14. The relay best suited for phase fault relaying for medium transmission lines is: a) Mho relay b) Reactance relay c) Impedance relay d) None of the above C 15. For ground fault, which of the relay is preferred: a) Plain impedance relay b) Directional relay c) Reactance relay d) Over-current relay C 16. The short circuit current of an alternator, inc case of line to line fault depends on its: a) Short circuit resistance b) Transient reactance c) Synchronous reactance d) None of the above C 17. Solid earthing is provided for the voltage below:

a) 100 kV b) 600 V c) 11 kV d) 66 kV B 18. A lightning arrester connected between the line and earth in a power system a) Protects the terminal equipment against travelling surges b) Protects the terminal equipment against lightning strokes c) Suppresses the high frequency oscillations in the line d) Reflects back the travelling waves approaching it A 19. Thermal relays are used for the protection of motors against over-current owing to: a) Short circuit b) Heavy loads c) Earth fault d) All the above B 20. Buchholz relay is: a) Located in the conservator tank b) Located in the transformer tank itself c) Connected in the pipe connecting main tank of transformer and conservator d) Installed in the circuit breaker C 21. Isolators are used for disconnecting a circuit when: a) Line is energised b) Line is on full load c) Line carries no current d) Can be operated under any condition C 22. Under-voltage relay is mostly used for:

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a) Transformer protection b) Bus-bar protection c) Motor protection d) Feeder protection C 23. Earth fault relays are: a) Directional relay b) Non-directional relay c) Short operate time relay d) Under voltage relay A 24. Differential relays are used for the protection of equipments against: a) Internal faults b) Over-current c) Reverse current d) Reverse power A 25. Admittance relay is: a) Non-directional relay b) Directional relay c) Differential relay d) None of the above B 26. The torque developed in Induction type relay is: a) Directly proportional to the current b) Directly proportional to the square of the current c) Directly proportional to square root of the current d) Inversely proportional to the current B 27. Buchholz relay is a: a) Oil actuating relay b) Current actuating relay c) Gas actuating relay d) Oil temperature-actuating relay C

28. The relay with inverse time characteristics will operate within: a) 10 msec b) 5 to 10 sec c) 10 to 20 sec d) above 25 sec B 29. The operation speed of a relay depends on: a) Rate of flux buildup b) Armature core air gap c) Spring tension d) All the above D 30. Which of the following relays has inherent directional characteristics: a) Mho relay b) Impedance relay c) Reactance relay d) Distance relay A

31. When D is the diameter of fuse wire, the fusing current will be proportional to (A) 1/D (B) 1/D2 (C) D3/2 (D) D1/2 . C 32. A material best suited for manufacturing of fuse wire is (A) Aluminium (B) Silver (C) Lead (D) Copper. B 33. In a circuit breaker the current which exists at the instant of contact separation is known as

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(A) re striking current (B) surge current (C) breaking current (D) recovery current. C 34. A Merz-price protection is suitable for (A) transformers (B) alternators (C) feeders (D) transmission lines. B 35. 'Kick fuse' has (A) square law characteristics (B) linear characteristics (C) inverse characteristics. C 36. Air blast circuit breakers for 400 kV. Power system are designed to operate in (A) 50 micro seconds (B) 50 milli seconds (C) 500 milli seconds (D) 50 seconds. B 37. Breaking capacity of a circuit breaker is usually expressed in terms of (A) Amperes (B) Volts (C) MW (D) MVA. D 38. Sulphur hexafluoride is a (A) Conductor of electricity (B) Semi-conductor (C) Inactive gas (D) Dielectric. D 39. The contact resistance is least affected by

(A) the mechanical force applied (B) the shape of the contact faces (C) the amount of surface contamination (D) the ambient temperature. D 40. The arc voltage produced in ac circuit breaker is (A) leading the arc current by 90° (B) lagging the arc current by 90° (C) In phase with the arc current (D) In phase opposition to the arc current. C 41. As the force on contact is increased, the contact resistance will (A) increase linearly (B) increase exponentially (C) remain unaltered (D) decrease. D

42. The heat produced at the contact point, due to passage of current, will least depend on (A) contact resistance (B) time during which the current flows (C) current flowing (D) temperature of the surrounding medium. D 43. For the contact and their material, which of the following should have low value (A) Contact resistance (B) Thermal capacity (C) Thermal conductivity (D) All of the above. A 44. Minimum arcing voltage will be least in case of (A) carbon

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(B) graphite (C) tungsten (D) silver. D 45. Minimum arcing voltage for platinum is 16 V. It can be therefore concluded that when the voltage is below 16 V (A) it will not be possible to interrupt the circuit (B) it will not be possible to pass the current (C) it will be possible to interrupt any value of current without arcing (D) it will be possible to interrupt any value of current without bringing contact closer to one another. C 46. Oil immersion of contacts is the method of (A) arc dispersion (B) arc prevention (C) de ionization (D) none of the above. A 47. Which of the following is not the method of arc dispersion ? (A) Oil immersion of contacts (B) Magnetic blow out of arc (C) Use of rectifiers (D) De ionization of arc path. C 48. Which of the following contact point metals has the highest melting point ? (A) Silver (B) Tungsten (C) Gold (D) Copper. B 49. The arc voltage produced in the circuit breaker is always

(A) in phase with arc current (B) leading the arc current by 90° (C) lagging the arc current by 90° . A 50. Ionization process during arc is generally accompanied by emission of (A) light (B) heat (C) sound (D) all of the above. D 51. Sparking between contacts can be reduced by ( A) inserting resistance in the line (B) inserting a capacitor in series with the contacts (C) inserting a capacitor in parallel with the contacts. C 52. For magnetic blow out of arc the magnetic field is produced (A) in the load circuit (B) parallel to the axis of the arc (C) at right angles to the axis of the arc. C 53. Cool gases are solids brought into the arc stream assist in quenching the arc mainly by (A) reducing current density (B) providing arc shield (C) De ionization (D) providing parallel paths. C 54. Sparking occurs when a load is switched off because the circuit has (A) high inductance (B) high capacitance (C) high resistance. A

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55. HRC fuses are (A) High resistance and Capacitance fuses (B) Heat reflecting cool fuses (C) Holding and Resisting current fuses (D) High rupturing capacity fuses. D 56. The following figure shows the voltage waveform across the pole of a circuit breaker; In this voltage R represents

(A) System voltage (B) Re striking voltage (C) Recovery voltage (D) Extinction of arc. B 57. In the above figure, D represents (A) Recovery voltage (B) Re striking voltage (C) System voltage (D) Extinction of arc. A 58. Best protection is provided by HRC fuses in case of (A) Open circuits (B) Short circuits (C) Overloads (D) None of the above. B 59. For motor circuit breakers, the time of closing the cycle is

(A) 0.001 sec (B) 0.01 sec (C) 0.10 sec (D) 0.003 sec. D 60. A relay used for protection of motors against overload is (A) Impedance relay (B) Electromagnetic attraction type (C) Thermal relay (D) Buchholz's relay. C 61. Fuse protection is used for current ratings up to (A) 10 A (B) 20 A (C) 50 A (D) 100 A. D 62. The fuse current in amperes is related with fuse wire diameter D as (A) I ∞ I/D (B) I ∞ D (C) I ∞ D3/2 (D) I ∞ D2. C 63. The acting contacts for a circuit breakers are made of (A) Stainless steel (B) Hard pressed carbon (C) Porcelain (D) Copper tungsten alloy. D 64. Ionization in a circuit breaker is not facilitated by (A) high temperature of surrounding medium (B) material of contacts (C) increase of field strength

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(D) increase of mean free path. B 65. Which circuit breaker is generally used in railway traction ? (A) SF6 gas circuit breaker (B) Air break circuit breaker (C) Vacuum circuit breaker (D) Minimum oil circuit breaker. B 66. A fuse wire should have (A) Low specific resistance and high melting point (B) Low specific resistance and low melting point (C) High specific resistance and high melting point (D) High specific resistance and low melting point. D 67. Fuse wire, protection, system is usually not used beyond (A) 10 A (B) 25 A (C) 50 A (D)100A. D 68. For extra high voltage lines which circuit breaker is preferred (A) Bulk oil circuit breaker (B) Vacuum circuit breaker (C) SF6 gas circuit breaker (D) Minimum oil circuit breaker. C 69. The number of cycles in which a high speed circuit breaker can complete its operation is (A) 3 to 8 (B) 10 to 18 (C) 20 to 30

(D) 40 to 50. A 70. Out of the following circuit breakers, which one has the lowest voltage range ? (A) Air-break circuit breaker (B) Tank type oil circuit breaker (C) Air-blast circuit breaker (D) SF6 circuit breaker. A 71. Which of the following circuit breaker can be installed on 400 kV line (A) Tank type oil circuit breaker (B) Miniature circuit breaker (C) Vacuum circuit breaker (D) Air blast circuit breaker. D 72. In a vacuum circuit breaker, the vacuum is of the order of (A) 10mm Hg (B)10-2mmHg (C) l0-6 mmHg (D)10-9mmHg. D 73. In modem EHV circuit breakers, the operating time between instant of receiving trip signal and final contact separation is, of the order of (A) 0.001 sec (B) 0.015 sec (C) 0.003 sec (D) 0.03 sec. D 74. In a HRC fuse the time between cut-off and final current zero, is known as (A) total operating time (B) arcing time (C) pre-arcing time (D) any of the above. B

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75. Fusing factor for a HRC fuse is (A) Minimum fusing current / Current rating (B) Minimum fusing current / Minimum rupturing time (C) Maximum fusing current / Minimum fusing current (D) Minimum fusing current / Prospective current of circuit. A 76. Which of the following circuit breakers does not use pneumatic operating mechanism (A) Air blast circuit breaker (B) SF6 blast circuit breaker (C) Air break circuit breaker (D) Bulk-oil circuit breaker. D 77. The contact resistance of a circuit breaker is. of the order of (A) 20 micro ohms ± 10 (B) 20milli ohms ± 10 (C) 20 ohms ± 10 (D) 200 ohms ± 10. A 78. The insulation resistance of high voltage circuit breaker is (A) 1k Ohm (B) 10 k Ohm (C) 20 Mega ohms (D) 2000 Mega ohm. D 79. There is definite objection to use of which of the following medium for extinguishing the arc in case of a circuit breaker ? (A) Air (B) SF6 gas (C) Vacuum (D) Water.

D 80. In a circuit breaker if the insulation resistance between phase terminal and earthed frame is less than the specified limit, the probable cause could be (A) moisture (B) dirty insulation surface (C) carbon or copper particles sticking to the internal surface (D) any of the above. D 81. If a circuit breaker does not operate on electrical compound, the probable reason could be (A) spring defective (B) trip circuit open (C) trip latch defective (D) any of the above. D 82. The normal frequency rms voltage that appears across the breaker poles after final arc extinction has occurred, is (A) recovery voltage (B) re striking voltage (C) supply voltage (D) peak voltage. A 83. The transient voltage that appears across the contacts at the instant of arc extinction is called (A) recovery voltage (B) re striking voltage (C) supply voltage (D) peak voltage. B 84. In a circuit breaker the active recovery voltage depends upon (A) power factor (B) armature reaction

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(C) circuit conditions (D) all of the above. D 85. A circuit breaker is (A) power factor correcting device (B) a device to neutralize the effect of transients (C) a waveform correcting device (D) a current interrupting device. D 86. The function of protective relay in a circuit breaker is (A) to each any stray voltages (B) to close the contacts when the actuating quantity reaches a certain predetermined value (C) to limit arcing current during the operation of circuit breaker (D) to provide additional safety in the operation of circuit breaker. B 87. Low voltage circuit breakers have rated voltage of less than (A) 220 V (B) 400V (C) 1000 V (D) 10,000 V. C 88. The fault clearing time of a circuit breaker is usually (A) few minutes (B) few seconds (C) one second (D) few cycles of supply voltage. D 89. The medium employed for extinction of arc in air circuit breaker is (A) SF6 (B) Oil

(C) Air (D) Water. C 90. Which of the following circuit breakers is preferred for EHT application (A) Air blast circuit breakers (B) Minimum oil circuit breakers (C) Bulk oil circuit breakers (D) SF6 oil circuit breakers. D 91. For high voltage, ac circuit breakers, the rated short circuit current is passed for (A) 0.01 sec (B) 0.1 sec (C) 3 seconds (D) 30 seconds. C 92. Which of the following is not a type of the contactor for circuit breakers ? (A) Electro-magnetic (B) Electro-pneumatic (C) Pneumatic (D) Vacuum. D 93. Interrupting medium in a contactor may be (A) air (B) oil (C) SF6 gas (D) any of the above. D 94. In air blast circuit breakers, the pressure of air is of the order of (A) 100 mm Hg (B) 1 kg/cm2 (C) 20 to 30 kg/cm2 (D) 200 to 300 kg/cm2 . C

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95. SF6 gas is (A) sulphur fluoride (B) sulphur difluoride (C) sulphurhexafluorine (D) sulphur hexafluoride. D 96. SF6 gas (A) is yellow in color (B) has pungent odor (C) is highly toxic (D) is non-inflammable. D 97. SF6 gas (A) is lighter than hydrogen (B) is lighter than air (C) has density 2-times as compared to that of air (D) has density 5 limes as compared to that of air. D 98. The pressure of SF6 gas in circuit breakers is of the order of (A) 100 mm Hg (B) 1 kg/cm2 (C) 3 to 5 kg/cm2 (D) 30 to 50 kg/cm2. C 99. While selecting a gas for circuit breaker, the property of gas that should be considered is (A) high dielectric strength (B) non-inflammability (C) non-toxicity (D) all of the above. D

2. Transmission & Distribution of Electrical

Power 1. Which of the following is not the trans-mission voltage in America? (A) 66 kV (B) l32 kV (C) 264 kV (D) 400 kV C 2. Which of the following is usually not the generating voltage ? (A) 6.6 kV (B) 9.9 kV (C) 11kV (D) 13.2 kV. B 3. Boosters are basically (A) inductors (B) capacitors (C) transformers (D) synchronous motors. C 4. Which of the following is not the distribution system normally used (A) 3 phase-4 wire (B) 3 phase-3 wire (C) Single phase - 3 wire (D) Single phase -4 wire. D 5. Conductors for high voltage transmission lines are suspended from towers (A) to reduce clearance from ground (B) to increase clearance from ground (C) to reduce wind and snow loads

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(D) to take care of extension in length during summer. B 6. Transmission efficiency increases as (A) voltage and power factor both increase (B) voltage and power factor both decrease (C) voltage increases but power factor decreases (D) voltage decreases but power factor increases. A 7. With same maximum voltage to earth, which ac system (with p.f. 0.8) will require more copper as compared to dc 2 wire system (A) single phase. 2 wire (mid point earthed) (B) single phase. 3 wire (neutral=1/2 outer) (C) three phase three wire (D) three phase-four wire (neutral = outer). D 8. When alternating current passes through a conductor (A) it remains uniformly distributed throughout the section of conductor (B) portion of conductor near the surface carries more current as compared to the core (C) portion of conductor near the surface carries less current as compared to the core (D) entire current passes through the core of the conductor. B 9. The fact that a conductor carries more current on the surface as compared to core, is known as (A) skin effect (B) corona (C) permeability (D) unsymmetrical fault. A

10. The effective resistance of a conductor will be the same as ohmic resistance when (A) current is in true sine wave form (B) voltage is low (C) power factor is unity (D) Current is uniformly distributed in the conductor cross-section. D 11. Skin effect results in (A) reduced effective resistance but increased effective internal reactance of the conductor (B) increased effective resistance but reduced effective internal reactance of. the conductor (C) reduced effective resistance as well as effective internal reactance (D) increased effective resistance as well as effective internal reactance. B 12. Skin effect depends on (A) size of the conductor (B) frequency of the current (C) resistivity of the conductor material (D) all of the above. D 13. The skin effect of a conductor will reduce as the (A) diameter increases (B) frequency increases (C) permeability of conductor material increases (D) resistivity of conductor material increases. D 14. Skin effect is proportional to (A) diameter of conductor (B) (diameter of conductor)1/2 (C) (diameter of conductor )2

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(D) (diameter of conductor )2. C 15. In overhead transmission lines the effect of capacitance can be neglected when the length of line is less than (A) 200 km (B) 160 km (C) 100 km (D) 80 km. D 16. For constant voltage transmission the voltage drop is compensated by installing (A) synchronous motors (B) capacitors (C) inductors (D) all of the above. A 17. The disadvantage of constant voltage transmission is (A) short circuit current of the system is increased (B) load power factor in heavy loads (C) large conductor area is required for same power transmission (D) air of the above. A 18. The surge impedance for over head line is taken as (A) 10-20 ohms (B) 50-60 ohms (C) 100-200 ohms (D) 1000-2000 ohms. C 19. Pin insulators are normally used up to voltage of about (A)100kV (B) 66 kV (C) 33 kV (D) 25 kV.

D 20. Strain type insulator arc used where the conductors arc (A) dead ended (B) at intermediate anchor towers (C) any of the above (D) none of the above. C 21. For 66 kV lines the number of insulator discs used are (A) 3 (B) 5 (C) 8 (D) 12. B 22. Ten discs usually suggest that the transmission line voltage is (A) 11 kV (B) 33 kV (C) 66 kV (D) 132 kV. D 23. The effect of corona is (A) increased energy loss (B) increased reactance (C) increased inductance (D) all of the above. A 24. Corona usually occurs when the electrostatic stress in the air around the conductor succeeds (A) 30 kV (maximum value)/cm (B) 22 kV (maximum value)/cm (C) 11 kV (rms value)/cm (D) 6.6 kv (rms value)/cm. A 25. Corona effect can be detected by (A) hissing sound

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(B) faint luminous flow of bluish color (C) presence of ozone detected by odor (D) all of the above. D 26. The current drawn by the line due to corona losses is (A) sinusoidal (B) square (C) non-sinusoidal C 27. Presence of ozone as a result of corona is harmful because (A) it gives bad odor (B) it corrodes the material (C) it transfers energy to the ground (D) reduces power factor. B 28. Between two supports, due to sag the conductor takes the form of (A) catenary (B) triangle (C) ellipse (D) semi-circle. A 29. The inductance of a single phase two wire line is given by (D is the distance between conductors and 2v is the diameter of conductor) (A) 0.4 loge (D/r) mH/km (B) 0.55 loge (D/r) mH/km (C) 0.4 loge (r/D) mH/km (D) 0.55 loge (r/D) mH/km. A 30. The effect of ice deposition on conductor is (A) increased skin effect (B) reduced corona losses (C) increased weight (D) reduced sag.

C 31. The effect of wind pressure is more predominant on (A) transmission lines (B) neutral wires (C) insulator (D) supporting towers. D 32. Which of the following statement is correct ? (A) Wind pressure reduces corona effects (B) Ice on conductors improves power factor (C) Wind pressure is taken to act in a direction at right angles to that for ice (D) Wind pressure and ice on conductors together improve regulation of power transmitted. C 33. Which of the following statements is incorrect ? (A) As the temperature rises the tension in the transmission line decreases (B) As temperature rises the sag in transmission lines reduces (C) Tension and sag in transmission lines are complementary to each other. C 34. Wooden poles for supporting transmission lines are used for voltages up to (A) 440 V (B)11 kV (C) 22 kV (D) 66 kV. C 35. If K is the volume of cable conductor material required to transmit power, then for the transmission of the same power,

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the volume of cable conductor required for single phase 2 wise AC system is (A) 2k (B) k cosφ (C) k/ cos2φ (D) 2k/ cos2p D 36. Maximum permissible span for wooden poles is (A) 10 meter (B) 20 meters (C) 60 meters (D) 200 meters. C 37. When transformers or switchgears are to be installed in a transmission line, the poles used are (A) I type (B) J type (C) H type (D) L type. C 38. For improving life, steel poles are galvanized. Galvanizing is the process of applying a layer of (A) paint (B) varnish (C) tar coal (D) zinc. D 39. The disadvantage of transmission lines as compared to cables is (A) exposure to lightening (B) exposure to atmospheric hazards like smoke, ice, etc. (C) inductive interference between power and communication circuits (D) all of the above. D

40. ACSR conductor implies (A) All conductors surface treated and realigned (B) Aluminum conductor steel reinforced (C) Anode current sinusoidally run (D) Anodized Core Smooth Run. B 41. The surge resistance of transmission lines is about (A) 50 ohms (B) 100 ohms (C) 250 ohms (D) 500 ohms. D 42. During storm the live conductor of public electric supply breaks down and touches the earth. The consequences will be (A) supply voltage will drop (B) supply voltage will increase (C) current will flow to earth (D) no current will flow in the conductor. C 43. In transmission system a feeder feeds power to (A) service mains (B) generating stations (C) distributors (D) all of the above. C 44. For transmission lines the standing wave ratio is the ratio of (A) maximum voltage to minimum voltage (B) maximum current to minimum voltage (C) peak voltage to rms voltage (D) maximum reactance to minimum reactance. A

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45. In a transmission line following arc the distributed constants (A) resistance and inductance only (B) resistance, inductance and capacitance (C) resistance, inductance, capacitance and short conductance. C 46. The bundling of conductors is done primarily to (A) reduce reactance (B) increase reactance (C) increase ratio interference (D) reduce radio interference. A 47. Which of the following regulation is considered to be the best (A) 2% (B) 30% (C)70% (D) 98%. A 48. The characteristic impedance of a transmission line depends upon (A) shape of the conductor (B) surface treatment of the conductors (C) conductivity of the material (D) geometrical configuration. of the conductors. D 49. For a distortion-less transmission line (G = shunt conductance between two wires) (A) R/L = G/C (B) RL=GC (C) RG=LC (D)RLGC=0 A 50. Guard ring transmission line (A) improves power factor

(B) reduces earth capacitance of the lowest unit (C) reduces transmission losses (D) improves regulation. B 51. When the power is to be transmitted over a distance of 500 km, the transmission voltage should be in the range (A) 33 kV - 66 kV (B) 66 kV - 100 kV (C) 110 kV - 150 kV (D) 150kV - 220kV. D 52. A relay used on long transmission lines is (A) mho's relay (B) reactance relay (C) impedance relay (D) no relay is used. A 53. Total load transmitted through a 3 phase transmission line is 10,000 kW at 0.8 power factor lagging. The I2R losses are 900 kW. The efficiency of transmission line is (A) 60% (B) 90% (C) 95% (D) 99%. B 54.Litz wires are used for intermediate frequencies.to overcome (A) corona effect (B) skin effect (C) radio interference (D) all of the above. B 55. In order to reduce skin effect at UHF (A) conductors are painted

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(B) conductors are anodized (C) copper lubes with silver plating are used (D) copper rods with silver plating are used. C 56. Shunt capacitance is usually neglected in the analysis of (A) Short transmission lines (B) Medium transmission lines (C) Long transmission lines (D) Medium as well as long transmission lines. A 57. The chances of corona are maximum during (A) summer heat (B) winter (C) dry weather (D) humid weather. D 58. The power transmitted will be maximum when (A) Sending end voltage is more (B) Receiving end voltage is more (C) Reactance is high (D) Corona losses are least. A 59. Neglecting losses in a transmission system, if the voltage is doubled, for the same power transmission, the weight of conductor material required will be (A) four times (B) double (C) half (D) one fourth. D 60. When two conductors each of radius r are at a distance D, the capacitance between the two is proportional to (A) loge (D/r)

(B) loge (r/D) (C) 1/loge (D/r) (D) 1/loge (r/D). C 61. In a transmission line having negligible resistance the surge impedance is (A) (L+C)1/2 (B) (C/L)1/2 (C) (1/LC)1/2 (D) (L/C)1/2 D 62. A relay used on short transmission lines is (A) Reactance relay (B) Mho's relay (C) Impedance relay (D) None of the above. A 63. In case the characteristic impedance of the line is equal to the load impedance (A) all the energy will pass to the earth (B) all the energy will be lost in transmission losses (C) the system will resonate badly (D) all the energy sent will be absorbed by the load. D 64. For a properly terminated line (A) ZR=ZO (B) Z/R > ZO (C) ZR < ZO (D) ZR =Z0 = 0. D 65. The dielectric strength of air at 250C and 76 cm/Hg is (A) 1 kV/cm (B) 1 kV/mm (C) 3 kV/cm (D) 30 kV/cm.

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D 66. The chances of corona are maximum in (A) domestic wiring (B) distribution lines (C) transmission lines (D) all of the above. C 67. Transmission lines link (A) service points to consumer premises (B) distribution transformer to consumer premises (C) receiving end station to distribution transformer (D) generating station to receiving end station. D 68. In case of open circuit transmission lines the reflection coefficient is (A) 1 (B) 0.5 (C) -1 (D) Zero. D 69. Impedance relay is used on (A) Short transmission lines (B) Medium transmission lines (C) Long transmission line (D) All the transmission lines. B 70. Which type of insulators are used on 132 kV transmission lines ? (A) Pin type (B) Disc type (C) Shackle type (D) Pin and shackle type. B 71. String efficiency can be improved by

(A) using Longer cross arm (B) grading the insulator (C) using a guard ring (D) any of the above. D 72. Minimum horizontal clearance of a low voltage transmission line from residential buildings must be (A) 11/2 feet (B) 3 feet (C) 4 feet (D) 8 feet. C 73. If a 66 kV lines passes over a residential building, the minimum vertical clearance from the roof of the building must be (A) 8 feet (B) 12 feet (C) 13 feet (D) 16 feet. C 74. Alternating current power is transmitted at high voltage (A) to safeguard against pilferage (B) to minimize transmission losses (C) to reduce cost of generation (D) to make the system reliable. B 75. Stranded conductors arc used for transmitting, power at high voltages because of (A) increased tensile strength (B) better wind resistance (C) ease-in handling (D) low cost. C 76. For the same resistance of line the ratio, weight of copper conductor/ weight of aluminium conductor , is

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(A) 0.50 (B) 0.75 (C) 1.50 (D) 2.0. D 77. The function of steel wire in a ACSR conductor is (A) to take care of surges (B) to prevent corona (C) to reduce inductance and hence improve power factor (D) to provide additional mechanical strength. D 78. In high voltage transmission lines the top most conductor is (A) R-phase conductor (B) Y- phase conductor (C) B-phase conductor (D) Earth conductor. D 79. For 11 kV line the inductance per km per phase will be of the order of (A) 1 H (B) 0.1 H (C) 1 mH (D) 0.1 mH. C 80. For 11 kV. line the capacitance per km per phase will be of the order of (A) 1 Farad (B) 0.1 Farad (C) 0.01 Farad (D) 0.01 microF. C 81. If 3000 kW power is to be transmitted over a distance of 30 km, the desirable transmission voltage will be (A) 11 kV

(B) 33 kV (C) 66 kV (D) 132 kV. B 82. The permissible voltage variation in transmission and distribution system is (A) ± 0.1% (B) ± 1% (C)±10% (D)± 25%. C 83. The voltage of transmission can be regulated by (A) use of tap changing transformers (B) switching in shunt capacitors at the receiving end during heavy loads (C) use of series capacitors to neutralize the effect of series reactance (D) any of the above methods. D 84. The most economic voltage for transmitting given power over a known distance by overhead transmission line is approximately (A) 3.6 kV/km (B) 1.6 kV/km (C) 2.6 kV/km (D) 3.6 kVkm. A 85. String efficiency is given by (A) (voltage across the string) / ((numbers of discs on the string) x (voltage across disc nearest to the conductor)) (B) ((voltage across the string) x (numbers of discs on the string)) / (voltage across disc nearest to the conductor) (C) ( (voltage across disc nearest to the conductor) x (numbers of discs on the string)) / (voltage across the string)

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(D) (voltage across disc nearest to the conductor))/ ((numbers of discs on the string) x (voltage across the string) A 86. For a 66 kV line having span of 200 meters between towers the approximate sag will be (A) 0.02 m (B) 0.2 m (C) 2 m (D) 20 m. C 87. In the above case if the span is doubled, the sag will be (A) 2 m (B) 4m (C) 8m (D) 1 m. C 88. The reflection coefficient for a short circuit line is (A) 1 (B) Zero (C) 0.5 (D) - 1. D 89. In case the height of transmission tower is increased (A) the line capacitance and inductance will not change (B) the line capacitance will decrease but line inductance will decrease (C) the line capacitance will decrease and line inductance will increase (D) the line capacitance will decrease but line inductance will remain unaltered. D

90. In a transmission line if booster transformer are to be used, preferred location will be (A) at the receiving end (B) at the sending end (C) at the intermediate point (D) any where in the line. C 91. A 70/6 ACSR conduction is an aluminium conductor steel reinforced, having (A) cross sectional area of aluminium as 70 mm2 and the cross-sectional area of steel as 6 mm2 (B) cross-sectional area of steel as 70 mm2

and the cross-sections area of aluminium as 6 mm2 (C) 70 aluminium conductors and 6 steel conductors (D) 80 steel conductors and 6 aluminium conductors. C 92. In aluminium conductors steel reinforced, the insulation between aluminium and steel conductors is (A) any insulator (B) bitumen (C) insulin (D) no insulation is required. D 93. Under no load conditions the current in a transmission line is due to (A) corona effects (B) capacitance of the line (C) back flow from earth (D) spinning reserve. B 94. Which distribution system is more reliable ? (A) Ring main system

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(B) Tree system (C) Radial system (D) All are equally reliable. A 95. Out of the following systems of distribution, which system offers the best economy ? (A) Direct current system (B) AC single phase system (C) AC 3 phase 3 wire system (D) AC 3 phase 4 wire system. A 96. What are the advantages of dc transmission system over ac transmission system ? (A) DC system is economical (B) There is no skin effect in dc system (C) Corona limits are highest for dc circuits as compared to ac circuits (D) All of the above. D 97. The main advantage of ac. transmission system over d.c. transmission system is (A) Easy transformation (B) Less losses in transmission over long distances (C) ) Less insulation problems (D) Less problem of instability. B 99. Step-up substations are associated with (A) distributors (B) consumer location (C) concentrated load (D) generating stations. D Questions 100 to 102 refer to figure given below :

100. A section of a single bus scheme is shown in the figure. In this figure B represents (A) Isolator (B) Circuit breaker (C) Current transformer (D) Inductance. C 101. An isolator is represented by (A) A (B) B (C) C (D) A and D. D 102. C represents (A) circuit breaker (B) Mho's relay (C) Earth switch (D) None of the above. A 103. When an alternator is connected to the infinite but bar and its excitation is gradually increased (A) the terminal voltage will rise (B) the terminal voltage will drop (C) the terminal voltage will remain unaltered (D) the terminal voltage will vary rapidly.

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C 104. Consumers having low power factor equipment are advised to install (A) tap changing transformer (B) capacitor bank (C) synchronous condensers (D) none of the above. B 105. A bus bar is rated by (A) current only (B) current and voltage only (C) current, voltage, frequency (D) current, voltage, frequency and short time current. D 106. Material generally used for bus bar is (A) copper (B) aluminium (C) steel (D) tungsten. B 107. Which of following properties has got higher value for aluminium as compared to copper? (A) Melting point (B) Specific gravity (C) Electrical resistivity (D) Thermal conductivity. C 108. For carrying a 100 A (rms) current the cross-sectional area of aluminium bus bar should be at least (A) 1 mm2 (B) 10 mm 2 (C) 25 mm 2 (D) 50 mm2 C

109. Isolators are used to disconnect a circuit when (A) line is on full load (B) line is energized (C) circuit breaker is not open (D) there is no current in the line. D 110. Tap changing transformers are used for (A) stepping up the voltage (B) stepping down the voltage (C) both stepping up and stepping down the voltage (D) supplying low voltage current for instruments. C 111. Which device automatically interrupts the supply in the event of surges (A) Earthing switch (B) Series reactor (C) Isolator (D) Circuit breaker. D 112. In a substation the equipment used to limit short circuit current level is (A) Series reactor (B) Coupling capacitor (C) Lightening switch (D) Isolator. A 113. Which of the following equipment is not installed in a substation ? (A) Shunt reactors (B) Exciters (C) Voltage transformers (D) Series capacitors. B 114. Which bus bar scheme offers the lowest cost ?

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(A) Single bus bar scheme (B) Ring bus bar scheme (C) Breaker and a half scheme (D) Main and transfer scheme. A 115. Which is the most expensive bus bar scheme ? (A) Single bus bar scheme (B) Ring bus bar scheme (C) Double bus bar double breaker (D) Main and transfer scheme. C 116. Current rating is not necessary in case of (A) Isolators (B) Circuit breakers (C) Load break switches (D) Circuit breakers and load break switches. A 117. Which of the following correctly represents the sequence of operations of isolator circuit breaker and earthing switch while opening a circuit (A) Close earthing switch - open circuit breaker open isolator (B) Open isolator - close circuit breaker - open earthing switch (C) Open circuit breaker - open isolator - close earthing switch (D) Close circuit breaker - close isolator - open earthing switch. C 118. Which of the following correctly presents the sequence of operations of isolator circuit breaker and earthing switch while closing a circuit (A) Ensure circuit breaker is closed - close isolator - open earthing switch

(B) Ensure circuit breaker is open - close isolator - open earthing switch if any close circuit breaker (C) Ensure circuit breaker is open - open isolator - open earthing switch if any - close circuit breaker. (D) None of the above. B 119. Which of the following type tests are conducted on isolators (A) Temperature rise test (B) Impulse stage with stand test (C) Short time current test (D) All of the above. D 120. In a balance 3 φ , 4 wire AC system, the phase sequence is RYB. If the voltage of R phase is. 230 < 0° V, then for Y phase (A) 230 < 0 V (B) 230 < 60° V (C) 230 < 90°V (D) 230 < 120° V. D 121. The relation between traveling voltage wave and current wave is (A) e = i (L/C) 1/2 (B) e = i (C/L) 1/2 (C) e = i (iL/C) 1/2 (D) (L/iC) 1/2 A 122. Steepness of the traveling waves is attenuated by (A) resistance of the line (B) inductance of the line (C) capacitance of the line (D) all of the above. A

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123. The protection against direct lightening strokes and high voltage steep waves is provided by (A) earthing of neutral (B) lightening arresters (C) ground wires (D) lightening arresters and ground wires. D 124. Voltages under Extra High Voltage are (A) 1 kV and above (B) 11 kV and above (C) 132 kV and above (D) 330 kV and above. D 125. In outdoor substation, the lightening arresters is placed nearer to (A) the isolator (B) the current transformer (C) the power transformer (D) the current breaker. C 126. Stability of a system is not affected by (A) Reactance of line (B) Losses (C) Reactance of generator (D) Output torque. B 127. A 10 MVA generator has power factor 0.866 lagging. The reactive power produced will be (A) 10 MVA (B) 8 MVA (C) 5 MVA (D) 1.34 MVA. C 128. In order to increase the limit of distance of transmission line (A) series resistances are used (B) synchronous condensers are used

(C) shunt capacitors and series reactors are used (D) series capacitors and shunt reactors are used. D 129. A 30 km transmission line carrying power at 33 kV is known as (A) short transmission line (B) long transmission line (C) high power line (D) ultra high voltage line. A 130. If K is the volume of conductor material required for 2 wire dc system with one conductor earthed, then the volume of cable conductor material required for transmission of same power in single phase 3 wire system is (A) K/3 cos φ (B) 5K cos2φ (C) K/ 5 cos2φ (D) 5K/ 8 cos2φ C 131. The permissible voltage variable in voltage in distribution is (A) 0.1% (B) 1% (C) 10% (D) 50%. C 132. Surge impedance of transmission line is given by (A) (L/C)1/2 (B) (C/L)1/2 (C) (CL)1/2 (D) 1/(CL)1/2 A 133. 750 kV is termed as (A) Medium high voltage

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(B) High voltage (C) Extra high voltage (D) Ultra high voltage. D 134. In case of transmission line conductors with the increase in atmospheric temperature (A) length increase but stress decreases (B) length increases and stress also increases (C) length decreases but stress increases (D) both length as well as stress decreases. A 135. If the height of transmission towers is increased, which of the following parameters is likely to change ? (A) Resistance (B) Inductance (C) Capacitance (D) None of the above. C 136. For increasing the capacity of a transmission line to transmit power which of the following must be decreased ? (A) Voltage (B) Capacitance (C) Line inductance (D) All of the above. C 137. In terms of constants A, B, C and D for short transmission lines, which of the following relation is valid ? (A) A = B = 1 (B) B = D = 0 (C) A = C = 1 (D) C=0. D 138.Which of the following is reduced due to the use of bundled conductors ?

(A) Capacitance of the circuit (B) lnductance of the circuit (C) Power loss due to corona (D) All of the above. C 139. The ratio of capacitance from line to line capacitance from line to neutral is nearly (A)1/4 (B) 1/2 (C) 1 (D) 2. A 140. Following effects are associated with transmission lines I. Corona effect II. Proximity effect III. Skin effect. The effect resistance of a conductor is increased by (A) I only (B) II and III only (C) I and III only (D) I. II and III. B 141. The sag of a transmission line is least affected by (A) self weight of conductors (B) temperature of surrounding air (C) current through conductor (D) ice deposited on conductor. C 142. The sag of the conductors of a transmission line is 1.5 m when the span is 100 m. Now if the height of supporting towers is increased by 20%, the sag will (A) increase by 20% (B) increase by 10% (C) reduced by 20% (D) remain unchanged.

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D 143. ACSR conductor having 7 steel stands surrounded by 25 aluminum conductor will be specified as (A) 7/25 (B) 7/32 (C) 25/7 (D) 25/32. C 144. The networks associated with transmission lines are I. T-network II. π network III. Tree net. A two terminal pair of network of a transmission line can be represented by (A) I only (B) II only (C) Either of I or II (D) Either of I, II or III. C 145. Which of the following relationships is not valid for short transmission lines ? (A) B = Z = C (B) A = D = 1 (C) Is = Ir (D) None of the above. A 146. In order to improve the steady state stability of an overhead transmission lines, which of the following methods can be adopted (A) Reducing impedance between the stations (B) Adopting quick response excitation systems (C) Using series capacitors to make X = (3 R)1/2 (D) Any of the above.

D 147. Transient disturbances arc due to (A) Switching operations (B) Load variations (C) Faults (D) Any of the above. D 148. Which of the following short circuit is the most dangerous ? (A) Line to line short circuit (B) Dead short circuit (C) Line to ground short circuit (D) Line to line and ground short circuit. B 149. In case line to line fault occurs, the short circuit current of an alternator will .depend on its (A) Synchronous reactance (B) Transient reactance (C) Short circuit resistance (D) All of the above. A 150. Transient state stability is generally improved by , (A) using high speed governors on machines by (B) using low inertia machines (C) dispensing with neutral grounding (D) any of the above. A 151. Aluminium is being favored as bus-bar material mainly because of (A) case of fabrication (B) low density (C) low cost (D) non availability of copper. C

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152. Which section can lie used for bus bar ? (A) bars (B) rods (C) tubes (D) any of the above. D 153. A string efficiency of 100% implies that (A) shunt capacitance is 1 MF (B) potential across each disc is same (C) potential across each disc is zero (D) one of the insulator disc is shorted. B 154. Steel poles for transmission lines need protection against (A) termites (B) borer (C) corrosion (D) all of the above. C 155. Which type of copper wire will have highest tensile strength ? (A) Soft drawn (B) Medium drawn (C) Hard drawn. C 156. Guy wire is used to (A) Support the pole (B) Provide protection against surges (C) Provide emergency earth route (D) Protect conductors against short circuiting. A 157. Which of the following is a leading power system ? (A) Underground cables (B) Reactors (C) Mercury arc rectifiers

(D)Transformers. A 158. Which of the following is a static exciter ? (A) dc separately excited generator (B) amplidyne (C) retool (D) rectifier. D 159. The service mains connect (A) distributor and consumer terminals (B) distributor and transformer (C) distributor and relay system (D) transformer and earth. A 160. System grounding is song (A) so that the floating potential on the lower voltage winding for a transformer is brought down to an insignificant value (B) so that arcing faults to earth would not set up dangerously high voltage on healthy phases (C) so that inductive interference between power and communication circuits can be controlled (D) for all above reasons. D 161. Hot template curves are plots of (A) conductor sage and span lengths (B) temperature and ground clearance curves (C) temperature and humidity (D) conductor weight and sag. A 169. In the analysis of short transmission lines which of the following is neglected ?

(A) I2 R loss (B) Shunt admittance (C) Series impedance

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(D) All of the above. B 170. In medium transmission lines the shunt capacitance is taken into account in (A) Tee method (B) Pie method (C) Steinmetz method (D) all of the above. D

3. Electric Traction

1. Overall efficiency of steam locomotive system is close to (A) 5 to 10% (B) 25 to 30% (C) 55 to 60% (D) 75 to 80%. A 2. In a steam locomotive electric power is provided through (A) battery system (B) diesel engine generator (C) overhead wire (D) small turbo generator. D 3. Maximum horse power of steam locomotive is (A) 100 (B) 500 (C) 1500 (D)2500. C 4. The pressure of steam in a locomotive is (A) 10-15 kg/cm2 (B) 20 - 30 kg/cm2 (C) 40 - 50 kg/cm2 (D) 80 - 90 kg/cm2.

A 5. The efficiency of diesel locomotives is nearly (A) 20 - 25 percent (B) 35 - 40 percent (C) 50 - 55 percent (D) 70 - 75 percent. A 6. The advantage of electric traction over other methods is (A) no pollution problems (B) faster acceleration (C) better braking action (D) all of the above. D 7. Suburban railways use (A) 1500 V DC (B) 440 V three phase AC (C) 660 V three phase AC (D) 3.3 kV three phase AC. A 8. Long distance railways use (A) 200 V DC (B) 25 kV Single phase AC (C) 25 kV Two phase AC (D) 25 kV Three phase AC. B 9. The range of horsepower for diesel locomotives is (A) 100 to 500 (B) 500 to 1000 (C) 1500 to 2500 (D) 4000 to 5500. C 10. Steam Engine provided on steam locomotives is (A) Single acting condensing type

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(B) double acting condensing type (C) double acting non - condensing type (D) single acting non condensing type. C 11. A submarine while moving under water, is provided driving power through (A) diesel engines (B) steam turbine (C) gas turbine (D) batteries. D 12. Overload capacity of diesel engines is usually restricted to (A) 1 % (B) 10% (C) 25% (D) 50%. B 13. Which locomotive has the highest operational availability (A) Diesel (B) Electric (C) Steam (D) All have same availability. B 14. Which motor is used in tramways (A) AC single phase capacitor start motor (B) AC three phase motor (C) DC series motor (D) DC shunt motor. C 15. A drive suitable for mines where explosive gas exist, is (A) Diesel engine (B) Steam engine (C) Battery locomotive (D) Any of the above. C

16. The advantage of electric braking is (A) is is instantaneous (B) more heat is generated during braking (C) it avoids wear of track (D) motor continue to remain loaded during braking. C 17. Which braking system on the locomotives is costly (A) Vacuum braking on steam locomotives (B) Vacuum braking on diesel locomotives (C) Regenerative breaking on electric locomotives (D) All breaking systems are equally costly. C 18. The acceleration rate of trains on suburban services is (A) 0.1 to 0.4 km phps (B) 0.8 to 1 km phps (C) 0.4 to 6.5 km phps (D) 10 to 26 km phps. C 19. The coasting retardation on trains is approximately (A) 0.16 km phps (B) 1.6 km phps (C) 16 km phps (D) 25 km phps. A 20. The coefficient of adhesion is (A) same on ac and dc traction systems (B) high in case of dc traction and low in ac traction (C) low in case of ac traction and high in dc traction. C 21. Braking retardation on suburban trains is

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(A) 0.3 to 0.5 km phps (B) 0.5 to 1 km phps (C) 3 to 5 km phps (D) 30 to 40 km phps. C 22. Power supply frequency for 25 kV single phase system is (A) 161 (B) 25 (C) 50 (D) 60. C 23. For supply on 25 kV, 50 Hz single phase, suitable motor for electric traction is (A) ac single phase split phase motor (B) ac single phase universal motor (C) dc shunt motor (D) dc series motor. D 24. Method of speed control used on 25 kV, 50 Hz single phase traction is (A) Tap changing control of transformer (B) Reduced current method (C) Series parallel operation of motors (D) Any of the above. A 25. The coefficient of adhesion is highest when (A) the rails are dry (B) the rails are oiled (C) the rails ark wet with dew (D) the rails are dusty. A 26. When the speed of the train is estimated taking into account the time of stop at a station in addition to the actual running time between stops, is known as (A) Average speed (B) Schedule speed

(C) Notching speed (D) Free running speed. B 27. A schedule speed of 45 km, per hour is required between two stops 1.5 km apart. The duration of stop is 20 seconds. The acceleration is 2.4 km phps and retardation is 3.2 km phps. For a simplified trapezoidal curve the maximum speed over the mil will be (A) 40 km per hour (B) 48 km per hour (C) 74 km per hour (D) 90 km per hour. C 28. Speed of locomotive is controlled by (A) gear box (B) flywheel (C) regulating steam to engine (D)applying brakes. C 29. The specific energy consumption for suburban services is usually (A) 18 to 25 watt-hours per tonne km (B) 50 to 75 watt-hours per tonne km (C) 125 to 150 watt-hours per tonne km (D) 155 to 200 watt-hours per tonne km. B 30. If the specific energy consumption for suburban services is 50 to 75 watts hours per tonne km, which of the following could be a representative figure for energy consumption on main line service (A) 150 to 200 watt-hours per tonne km (B) 100 to 125 watt-hours per tonne km (C) 50 to 75 watt-hours per tonne km (D) 20 to 30 watt-hours per tonne km. D 31. Specific energy consumption is least in

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(A) urban service (B) sub-urban service (C) main-line service (D) equal for all types of services. C 32. Bearings used to support axles of rolling stock are (A) Bush bearings (B) Journal bearings (C) Ball bearings (D) Roller bearings. D 33. If the coefficient of adhesion on dry rails 0.25. which of the following could be the value for wet rails ? (A) 0.32 (B) 0.25 (C)0.245 (D) 0.15. D 34. A train has a schedule speed of 36 km per hour on a level track. If the distance between the stations is 2 km and the stoppage is 30 seconds the actual time of run will be (A) 260 seconds (B) 230 seconds (C) 200 seconds (D) 170 seconds. D 35. B0B0 locomotives have two bogies with (A) four driving axles each with individual driving motors (B) three driving axles with group drives (C) two driving axles with group drives (D) two driving axles with individuals drive motor. D

36. A locomotive exerts a tractive effort of 30,000 Newtons in pulling a train at 50 km per hour on the level hack. It is to haul the same train at the same speed on a gradient and the tractive effort required is 45000 Nw. The horse power delivered by the motor will be more if it is driven by (A) dc series motors (B) induction motor (C) same in both cases. B 37. A composite system consists of (A) a combination of diesel engine and dc series motor (B) a combination of diesel engine and ac single phase motor (C) single phase power received is converted into dc or three phase power ac system (D) use of combination of dc and ac motors on the same locomotive. C 38. Horse power of steam locomotives is (A) Up to 1500 (B) 1500 to 2500 (C) 2500 to 4000 (D) more than 4000. A 39. Horse power of diesel locomotives is (A) 1000 to 1500 (B) 1500 to 2500 (C) 2500 to 5000 (D) 5000 to 10,000. B 40. Locomotives with manometer bogie have (A) lot of skidding (B) low coefficient of adhesion (C) uneven distribution of tractive effect

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(D) suitability for passenger as well as freight service. D 41. The speed time curve for a local train is shown in Figure. In this AB represents

(A) Coasting (B) Acceleration (C) Braking (D) Regeneration. A 42. The duration for braking is represented by the time (A) 0-t1 (B) 0-t2 (C)t1 - t2 (D)t2- t1 D 43. Area under the curve represents (A) average speed (B) average acceleration (C) net acceleration (D) distance traveled. D 44. From the figure it can be concluded that (A) rate of acceleration is the same as the rate of acceleration during braking (B) average acceleration is zero

(C) time taken during coasting is equal to the time during acceleration and braking (D) during coating the acceleration is negative. D 45. For tramways the return circuit is (A) through cables (B) through rails (C) through neutral wire (D) through common earthling. B 46. For 600 V dc line for tram cars (A) track is connected to negative of the supply (B) track is connected to positive of the supply (C) track is connected to mid voltage of 300 V (D) none of the above. A 47. Overhead lines for power supply to tramcars are at a minimum height of (A) 2 m (B) 5 m (C) 10 m (D) 15 m. C 48. Which of the following traction system is latest used in the world ? (A) 3 phase 3.7 kV (B) 20 kV, 50 Hz. single phase (C) 600 V, DC (D) 3 kV, DC. A 49. Which of the following frequencies not common in low frequency traction system ? (A) 161 Hz (B) 25 Hz

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(C) 40 Hz. C 50. In a long distance electric train, power for lighting in passenger coach is provided (A) through locomotive (B) directly through overhead electric line (C) through individual generator of bogie and batteries (D) through rails. C 51. In Kando system (A) single phase supply is converted into three phase system (B) single phase ac is converted into dc (C) three phase ac is converted into dc (D) dc supply is due to run dc motors. A 52. Free running and coasting periods arc generally long in ease if (A) urban service (B) sub-urban service (C) main-line service (D) all of the above. C 53. Which of the following factor affects specific energy consumption ? (A) Distance between stops (B) Gradient (C) retardation and acceleration values (D) All of the above. D 56. At an average the coal consumption per km in case of steam engine is nearly (A) 28 to 30 kg (B) 80 to 100 kg (C) 150 to 160 kg (D) 200 to 250 kg. A

57. Unbalanced forces are maximum in case of (A) electric locomotive (B) diesel locomotives (C) Petrol locomotives (D) steam locomotives. D 58. Maintenance requirements are least in case of (A) electric locomotives (B) diesel locomotives (C) steam locomotives. A 59. If the resistance to electric train is given by Fr = a + bv + cv2 In this equation constant c is likely to cover (A) air resistance (B) frictional resistance (C)flange resistance (D) track resistance. A 63. When a locomotive for Railways is designated as WAM1, in this the letter W indicates that (A) the locomotive is to run on broad guage track (B) the locomotive is to run on meter guage track (C) the locomotive is for shunting duty (D) the locomotive is for good train only A 64. An ideal traction system should have (A) high starting tractive effort (B) equipment capable of withstanding large temporary overloads (C) easy speed control (D) all of the above. D

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67. The main difference between speed-time curves of mainline service as compared to suburban services lies in (A) longer free running periods (B) longer coasting periods (C) shorter acceleration gand braking periods (D) all of the above. D 71. Energy consumption in propelling the train is required for (A) acceleration (B) work against gravity while moving up the gradient (C) work against the resistance to motion (D) all of the above. D 72. Quadrilateral speed-time curve is the closer approximation for (A) main line service (B) suburban service (C) urban service (D) urban and suburban service. D 73. Distance between the rails for meter gauge track is (A) 2' - 6 3/8" (B)3'-4 3/4" (C) 4' - 6 1/2" (D) One meter. D

4. Basic Electrical Engineering 1. Resistivity of a wire depends on (A) length (B) material (C) cross section area (D) none of the above. B 2. When n resistances each of value r are connected in parallel, then resultant resistance is x. When these n resistances are connected in series, total resistance is (A) nx (B) rnx (C) x / n (D) n2 x. D 3. Resistance of a wire is r ohms. The wire is stretched to double its length, then its resistance in ohms is (A) r / 2 (B) 4 r (C) 2 r (D) r / 4. B 4. Kirchhoff's second law is based on law of conservation of (A) charge (B) energy (C) momentum (D) mass. B 5. The diameter of the nucleus of an atom is of the order of (A) 10 -31 m (B) 10 -25 m (C) 10 -21 m (D) 10 -14m. D

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6. The mass of proton is roughly how many times the mass of an electron? (A) 184,000 (B) 184,00 (C) 1840 (D)184. C 7. The charge on an electron is known to be 1.6 x 10-19 coulomb. In a circuit the current flowing is 1 A. How many electrons will be flowing through the circuit in a second? (A) 1.6 x 1019 (B) 1.6 x 10-19 (C) 0.625 x 1019 (D) 0.625 x 1012. C 8. Two bulbs marked 200 watt-250 volts and 100 watt-250 volts are joined in series to 250 volts supply. Power consumed in circuit is (A) 33 watt (B) 67 watt (C) 100 watt (D) 300 watt. B 9. Ampere second could be the unit of (A) power (B) conductance (C) energy (D) charge. D 10. Which of the following is not the same as watt? (A) joule/sec (B) amperes/volt (C) amperes x volts (D) ( amperes )2 x ohm. B

11. One kilowatt hour of electrical energy is the same as (A) 36 x 105 watts (B) 36 x 10s ergs (C) 36 x 105 joules (D) 36 x 105 B.T.U. C 12. An electric current of 5 A is same as (A) 5 J / C (B) 5 V / C (C) 5 C / sec (D) 5 w / sec. C 13. An electron of mass m kg and having a charge of e coulombs travels from rest through a potential difference of V volts. Its kinetic energy will be (A) eV Joules (B) meV Joules (C)me / V Joules (D)V / me Joules. A 14. The value of the following is given by 100 (kilo ampere ) x ( micro ampere ) 100 milli ampere * 10 ampere (A) 0.001 A (B) 0.1 A (C) 1 A (D) 10A. B 15. A circuit contains two un-equal resistances in parallel (A) current is same in both (B) large current flows in larger resistor (C) potential difference across each is same (D) smaller resistance has smaller conductance. C

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16. Conductance is expressed in terms of (A) ohm / m (B) m / ohm (C) mho / m (D) mho. D 17. Which of the following could be the value of resistivity of copper? (A) 1.7 x 10-8 ohm-cm (B). 1.7 x 10-6 ohm-cm (C). 1.6 x 10-5 ohm-cm (D). 1.7 x 10-4 ohm-cm B 18. A copper wire of length l and diameter d has potential difference V applied at its two ends. The drift velocity is vd. If the diameter of wire is made d/3, then drift velocity becomes (A) 9 vd (B) vd / 9 (C)vd /3 (D)vd. D 19. Two resistances R1 and R2 give combined resistance of 4.5 ohms when in series and 1 ohm when in parallel. The resistances are (A)3 ohms and 6 ohms (B)3 ohms and 9 ohms (C)1.5 ohms and 3 ohms (D)1.5 ohms and 0.5 ohms. C 20. We have three resistances of values 2 Ω, 3 Ω and 6 Ω. Which of the following combination will give an effective resistance of 4 Ω? (A) All the three resistances in parallel (B) 2 Ω resistance in series with parallel combination of 3 Ω and 6 Ω resistance

(C) 3 Ω resistance in series with parallel combination of 2 Ω and 6 Ω resistance (D) 6 Ω resistance in series with parallel combination of 2 Ω and 3 Ω resistance. B 21. Three equal resistors connected in series across a source of emf together dissipate 10 watts of power. What would be the power dissipated in the same resistors when they are connected in parallel across the same source of emf? (A) 10 watts (B) 30 watts (C) 90 watts (D) 270 watts. C 22. Current I in the figure is

(A)1.5A (B)0.5A (C)3.5A (D)2.5A A 23. Four identical resistors are first connected in parallel and then in series. The resultant resistance of the first combination to the second will be (A) 1 / 16 times (B) 1 / 4 times (C) 4 times (D) 16 times.

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A 24. Twelve wires of same length and same cross-section are connected in the form of a cube as shown in figure below. If the resistance of each wire is R, then the effective resistance between P and Q will be

(A)R (B) 5 / 6 R (C) 3 / 4 R (D) 4 / 3 R. B 25. When P = Power, V = Voltage, I = Current, R = Resistance and G = Conductance, which of the following relation is incorrect? (A) V = √ (PR) (B). P= V2G (C) G= P / I2 (D) I =√ (P / R) C 26. The unit of electrical conductivity is (A) mho / metre (B) mho / sq. m (C) ohm / metre (D) ohm / sq. m. A

27. Which of the following bulbs will have the least resistance ? (A) 220 V, 60 W (B) 220 V, 100 W (C) 115 V, 60 W (D) 115 V, 100 W. D 28. The ratio of the resistance of a 100 W, 220 V lamp to that of a 100 W, 110 V lamp will be nearly (A) 4 (B)2 (C) 1 / 2 (D) 1 / 4 A 29. The resistance of a 100 W, 200 V lamp is (A) 100 ohm (B) 200 ohm (C) 400 ohm (D) 1600 ohm. C 30. Two 1 kilo ohm, 1/2 W resistors are connected in series. Their combined resistance value and wattage will be (A) 2 kΩ, 1/2 W (B) 2 kΩ, 1 W (C) 2 kΩ, 2 W (D) l kΩ, 1/2 W. B 31. Which method can be used for absolute measurement of resistances ? (A)Ohm's law method (B)Wheatstone bridge method (C)Releigh method (D) Lortentz method. B

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32. Three 3 ohm resistors are connected to form a triangle. What is the resistance between any two of the corners? (A) 3 / 4 ohms (B) 3 ohms (C) 2 ohms (D) 4/3 ohm. C 33. Five resistances are connected as shown in figure below. The equivalent resistance between the points A and B will be

(A) 35 ohms (B) 25 ohms (C) 15 ohms (D) 5 ohms. D 34. How many different combinations may be obtained with three resistors, each having the resistance R ? (A) 3 (B) 4 (C) 5 (D) 6. B 35. A wire of 0.14 mm diameter and specific resistance 9.6 micro ohm-cm is 440 cm long. The resistance of the wire will be (A) 9.6 ohm (B) 11.3 ohm

(C) 13.7 ohm (D) 27.4 ohm. D 36. Ohm's law is not applicable to (A) DC circuits (B) high currents (C) small resistors (D) semi-conductors. D 37. A metal resistor has resistance of 10 ohm at 0°C and 11 ohms at 160°C, the temperature coefficient is (A) 0.00625 / °C (B) 0.0625 /°C (C) 0.000625 /°C (D) 0.625 /°C. C Questions 38 to 40 refer to Figure given below.

Five resistances are connected as shown and the combination is connected to a 40 V supply. 38. Voltage between point P and Q will be (A) 40 V (B) 22.5 V (C) 20 V (D) 17.5 V. B 39. The current in 4 ohm resistor will be

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(A) 2.1 A (B) 2.7 A (C) 3.0 A (D) 3.5 A. D 40. Least current will flow through (A) 25 ohm resistor (B) 18 ohm resistor (C) 10 ohm resistor (D) 5 ohm resistor. A 41. Total power loss in the circuit is (A)10W (B) 50.2 W (C) 205 W (D) 410 W. C 42. A resistance of 5 ohms is further drawn so that its length becomes double. Its resistance will now be (A) 5 ohms (B) 7.5 ohms (C) 10 ohms (D) 20 ohms. D 43. Specific resistance of a substance is measured in (A) ohms (B) mhos (C) ohm-cm (D) cm/ohm. C 44. A wire of resistance R has it length and cross-section both doubled. Its resistance will become (A) 4 R (B)2 R (C) R (D) R / 4.

C 45. Ohm's law is not applicable in all the following cases except (A) Electrolytes (B) Arc lamps (E) Insulators (A) Vacuum ratio values. C 46. The element of electric heater is made of (A) copper (B) steel (C) carbon (D) nichrome. D 47. 5xl016 electrons pass across the section of a conductor in 1 minute 20 sec. The current flowing is (A) 1mA (B) 0.1 mA (C) 0.01mA (D) 10 mA. B 54. For the circuit shown below the current “I” flowing through the circuit will be

(A) 1 / 2 A (B) 1 A (C) 2 A (D) 4 A. C

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55. A cube of material of side 1 cm has a resistance of 0.002 ohm between its opposite faces. If the same volume of the material has a length of 8 cm and a uniform cross-section, the resistance of this length will be (A) 0.032 ohm (B) 0.064 ohm (C) 0.096 ohm (D) 0.128 ohm. D 56. A standard 60 W bulb is in series with a room heater and connected across the mains. If the 60 W bulb is replaced by 100 W bulb (A) the heater output will increase (B) the heater output will reduce (C) the heater output will remains unaltered. A 57. Two aluminium conductors have equal length. The cross-sectional area of one conductor is four times that of the other. If the conductor having smaller cross-sectional area has a resistance of 100 ohms the resistance of other conductor will be (A) 400 ohms (B) 100 ohms (C) 50 ohms (D) 25 ohms. D 58. A nichrome wire used as heater coil has the resistance of 1 ohm/m. For a heater of 1000 W at 200 V, the length of wire required will be (A) 10 m (B) 20 m (C) 40 m (D) 80 m. C

59. The hot resistance of a tungsten lamp is about 10 times the cold resistance. Accordingly, cold resistance of a 100 W, 200 V lamp will be (A) 4000 ohm (B)400 ohm (C)40 ohm (D)4 ohm. C 60. Variable resistors are (A)Wire wound resistors (B)Thin film resistors (C)Thick film resistors (D) All of the above. A 61. Low resistance can be accurately measured by (A) Kelvin bridge (B )Wheat stone bridge (C) Wein's bridge (D) None of the above. A 62. A heating element of a hot plate on an electric cooking range draws 12 amperes from 240 V mains. How many kWh of energy will be consumed in one hour and 15 minutes (A) 1.2 (B) 3.2 (C) 6.0 (D) 7.2. B 63. Temperature coefficient of resistance is expressed in terms of (A) ohms / ohms oC (B) mhos / ohm oC (C) mhos / oC (D) ohms / oC. A

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64. If R1 is the resistance of a coil of copper at t oC and RT is the resistance at T oC and also the resistance temperature coefficient of copper per degree centrigrade at 0oC is 1/234.45, then Rt/RT (A) (1+t) / (1+T) (B) (1+ 234.45t) / (1+234.45 T) (C) (234.45 + t) / (234.45 + T) (D) (234.45 + t2 ) / (234.45 + T 2). C 65. Resistivity is usually expressed in terms of (A) mho (B) ohm / oC (C) ohms/cm-square (D) ohms/cm-cube. D 66. Which material is expected to have least resistivity? (A) Copper (B) Lead (C) Mercury (D) Zinc. A 67. The shunt winding of a motor has a resistance of 85 ohm at 22oC. When the motor runs at full load, its resistance increases to 100 ohms. The resistance temperature coefficient of winding per 0oC is 0.004. The rise in temperature of the winding will be nearly (A) 20oC (B) 50oC (C)70oC (D) 100oC. C 68. The resistance temperature coefficient is defined as

(A) increase in resistance per degree centigrade (B) decrease in resistance per degree centigrade (C) the ratio of increase in resistance per degree centigrade to the resistance at 0oC (D) the ratio of increases in resistance per degree centigrade to the rate of rise of resistance at 0oC. C 69. Two coils connected in series have resistance of 600 ohm and 300 ohm and temperature coefficients of 0.1% and 0.4% respectively. The resistance of the combination at 50oC will be (A) 1050 ohm (B)1001 ohm (C)1600 ohm (D) 990 ohm. D 70. A 100 W, 200 V filament lamp has operating temperature of 2000oC. The filament material has resistance temperature coefficient of 0.005 at 0oC per oC. The current taken by the lamp at the instant of switching with 200 V supply with filament temperature of 20oC will be (A) 1 A (B) 3 A (C) 5 A (D) 10A. C 71. A fuse is always installed in a circuit is (A) Series (B) Parallel. A 72. The rating of fuse wire is expressed in terms of (A) Ohms (B) Mhos

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(C) Amperes (D) Watts. C 73. Which of the following material is not used as fuse material? (A) Silver (B) Copper (C) Aluminium (D) Carbon. D Questions 74 to 78 refer to Figure below.

74. The voltage drop across the resistor 9 ohm will be (A)18 V (B) 12 V (C) 9 V (D) 6 V. A 75. The voltage drop will be least in which resistor ? (A) 2 ohm (B) 3 ohm (C) 6 ohm (D) 3 ohm and 6 ohm. D 76. The current through 6 ohm resistor will be (A) 1 A (B) 2 A (C) 3 A (D) 4 A.

C 77. The ratio of power dissipated in circuit ADB to that in circuit ABC will be (A) 1 (B) 1.5 (C)0.67 (D) 2. B 78. Total power dissipated in the circuit is (A) 80 W (B)100 W (C)120 W (D) 150 W. C 79. The current carrying capacity of the fuse material depends on (A) cross-sectional area (B) length (C) material (D) all of the above. D 80. According to the fuse law, the current carrying capacity varies as (A) diameter (B) (diameter)3/2 (C) 1 / diameter (D)1 / (diameter)2. B Questions 81 to 83 refer to Figure given below.

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81. For the circuit shown in Figure above, the value of current I will be (A) 10A (B) 15A (C) 20A (D) 25A. D 82. The combined resistance of the circuit is (A) 10 ohms (B) 5 ohms (C) 4 ohms (D) 2 ohms. C 83. Total power dissipated in the circuit is (A) 2.5 kW (B) 5.0 kW (C) 7.5 kW (D)10 kW. A 84. A 100 W bulb is connected in series with a room heater of 750 W. What will happen if the bulb is replaced by a 60W bulb? (A) Heater output will increase (B) Heater output will decrease (C) Heater output will remain unchanged (D) Bulb will not glow. B 85. An immersion rod heats a bucket of water in 15 minutes. In order that the water should boil in 10 minutes (A) length of heating element of the rod should be increased (B) length of heating element of the rod should be reduced (C) supply voltage should be reduced (D) heating element of larger diameter should be used. B

86. A lamp of 100 W at 200 V is supplied current at 100 volts. It will be equivalent to the lamp of (A) 50 W (B) 40 W (C) 25 W (D) 10 W. C 87. Two electric bulbs of 100 W, 200 V are put in series and the combination is supplied 100 V. The power consumption of each bulb will be (A) 100 / 2 W (B) 100 / 4 W (C) 100 / 8 W (D) 100 / 16 W. D Questions 88 to 91 refer to Figure given below.

88. Three lamps are in circuit as shown in Figure given above. The lamp of 100 W will have maximum brightness when (A) key k1 is closed, k2 is open and k3 is closed (B) k1 is open, k2 is closed and k3 is open (C) k1 is open, k2 is closed and k3 is also closed

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(D) k1 is closed, k2 is open and k3 is also open. B 89. When switches k1 and k2 are open and k3 is closed (A) 100 W lamp will glow brighter than 40 W lamp (B) 40 W lamp will glow brighter than 100 W lamp (C) Both will glow at their full brightness (D) Both will glow at less than their full brightness. B 90. Which of the following statements is necessarily correct ? (A) 40 W bulbs will always glow at full brightness (B) 100 W bulb will always glows at full brightness (C) Whatever be the position of keys, at least one 40 W bulb will always glow (D) Whenever current flows through the circuit, 100 W bulb will always glow. D 91. 40 W bulb A will be least bright when (A) only keys k1 and k2 are open (B) only keys k2 is open (C) only keys k3 is open (D) all keys are closed. A 92. The power consumption of the circuit will be maximum when (A) key k1 and k3 are closed and k2 is open (B) key k1 is closed, k2 and k3 are open (C) key k1 and k2 are closed and k3 is open (D) all the keys are closed. A 93. Which of the following lamps will have least resistance at room temperature ?

(A) 200 W, 220 V (B) 100 W, 220 V (C) 60 W, 220 V (D) 25 W, 220 V. A 94. Filaments of electric bulbs are usually made of (A) Nichrome (B) Tungsten (C) Copper (D) Carbon. B 95. The value of supply voltage for 500 W ,5 ohm load is (A) 500 V (B) 100V (C) 50 V (D) 10V. C 96. Which resistor will be physically larger in size ? (A)10 ohm, 50 W (B) 100 ohm, 10 W (C) 1 kohm, 1 W (D) 10 Mohm, 1/ 2 W. A 97. Four resistances R1 , R2, R3 and R4 are connected in series against 220 V supply. The resistances are such that R1> R2> R3> R4. The least power consumption will be in (A) resistor R1 (B) resistor R2 (C) resistor R3 (D) resistor R4. D 98. 100 resistors of 100 ohms each arc connected in parallel. Their equivalent resistances will be (A) 10,000 ohms

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(B) 100 ohms (C) 1 ohm (D) 1/ 10000 ohm. C 99. For a fixed supply voltage the current flowing through a conductor will decrease when (A) cross-sectional area of the conductor is increased (B) length of the conductor is increased (C) length of the conductor is reduced (D) cross-sectional area is increased and length is decreased. B 100.When current flows through heater coil it glows but supply wiring does not glow because (A) supply wiring is covered with insulation layer (B) current through supply line flows at slower speed. (C) supply wires arc made of superior material (D) resistance of heater coil is more than that supply wires. D 101. The resistance of 1 meter length of 18 gauge copper wire is k ohm. The resistance of one metre length of 24 gauge copper wire will be (A) k / 2 ohm (B) 18 / 24 kohm (C) k ohm (D) more than k ohm. D 103. If the length and diameter of a conductor is tripped, the resistance will increase approximately by (A) 66 2/3 % (B) 33 1/3 %

(C)-66 2/3 % (D) -33 1/3 %. C 104. If the resistance of an incandescent light bulb changes as the voltage across the bulb is changed, which of the following is true ? (A) The internal inductance of the bulb causes this change (B) The bulb is said to have a low ionization potential (C) The bulb has constant resistance of the current through the bulb is changed (D) The bulb is a type of non-linear resistance. D 105. Which method can be used for absolute measurement of resistance ? (A) Ohm's law method (B) Wheatstone bridge method (C) Raleigh method (D) Lortentz method. B 106. Two 1 kilo ohm, 1/2 W resistors are connected in series. Their combined resistance value and wattage will be (A) 2 kohm, 1 / 2 W (B) 2 kohm, 1 W (C) 2kohm, 2 W (D) 1 kohm, 1 / 2 W. B 107. The resistance of 100 W, 200 V tamp is (A) 100 ohm (B) 200 ohm (C) 400 ohm (D) 1600 ohm. C

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108. A cylindrical wire is compressed in length by 10%. The percentage decrease in the resistance will be (A) 16% (B) 19% (C) 20% (D) 25%. B 109. Three resistance of 6 ohm each are connected as shown in Figure given below. The equivalent resistance between X1 and X2 is

(A) 2 ohm (B) 4 ohm (C) 8 ohm (D) 12 ohm. A 110. The unit of conductance is (A) per ohm (B) ohm/m (C) mho/m (D) mho. D 111. Ohm's law is not applicable in all the following cases except (A) Electrolysis (B) Arc lamps (C) Insulators (D) Vacuum radio valves. C 112. In which of the following circuits will the voltage source produce the most current?

(A) 10 V across a 10 ohm resistance (B) 10 V across two 10 ohm resistance in series (C) 10 V across two 10 ohm resistances in parallel (D) 1000 V across Mohm resistance. C 113. A piece of sliver wire has a resistance of 1 ohm. A manganin wire has specific resistance 30 times that of silver. The resistance of a manganin wire of one fourth length and one third diameter will be (A) 6 / 5 ohm (B) 1 ohm (C) 67.5 ohm (D) 86.75 ohm. C 114. A cube of material of side 1 cm has a resistance of 0.002 ohm between its opposite faces. If the same volume of the material has a length of 8 cm and a uniform cross-section, the resistance of this length w ill be (A) 0.032 ohm (B) 0.064 ohm (C) 0.096 ohm (D) 0.128 ohm. D 115. The unit of conductivity is (A) mho / m (B) mho / sq. m (C) ohm / m (D) ohm / sq. m. A 116. For the circuit shown in the figure given below, the meter will read

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(A) 1 A (B) 5 A (C) 10 A (D) 25 A. C 117. For the circuit shown in figure given below, the reading in the ammeter A w ill be

(A) 2 A (B) 0.5 A (C) 0.4 A (D) 0.2 A. C 118. According to Joule law heat produced by a current I while in flowing through a material of resistance R for a length of time T, is proportional to (A) T only (B) (RT) (C) (IRT) (D) (I2RT). D 119. In the color code for resistances black color represents the number (A) 0

(B) 1 (C) 2 (D) 3. A 120. In the color code white color represents the number (A) 9 (B) 8 (C) 6 (D) 5. A 121. In the color code number 3 is represented by (A) blue (B) orange (C) grey (D) violet. B 122. The condition for the validity under Ohm's law is (A) Temperature at positive end should be more than the temperature at negative end (B) Current should be proportional to the size of resistance (C) Resistance must be wire wound type (D) Resistance must be uniform. D 123. In which figure the relationship between voltage V and current I is in accordance with Ohm's law ?

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(A) Figure A (B) Figure B (C) Figure C (D) Figure D. B 124. Production of heat due to current is related by which law (A) Ohm's law (B) Joule's law (C) Kelvin's law (D) Maxwell's law. B 126. The maximum power that can be distributed in the load in the circuit shown in

(A) 3 watts (B) 6 warts (C) 6.75 watts

(D) 13.5 watts. C 129. The resistance to the flow of current through a copper wire (A) increases as the length of wire decrease (B) decreases as the diameter of wire decreases (C) increases as the length of wire increases (D) decreases as the length of wire increases. C 130. For the same voltage, the ratio Resistance of 100 W lamp Resistance of 25 W lamp is: (A) 1 (B) 4 (C)16 (D)1 / 4. D 131. The voltage drop across a resistor of 100 ohm is 10 volts. The wattage of the resistor must be (A) 1 / 2 W (B) 1 W (C) 2 W (D) 4 W. B 132. A 100 volt bulb has a resistance of 500 ohms. The number of hours it can work for every kWh of energy consumed will be (A) 20 (B) 40 (C) 50 (D) 60. C 133. A semi-conductor is (A) one which conducts only half of applied voltage

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(B) a material whose conductivity is same as between that of a conductor and an insulator (C) a material made of alternate layers of conducting material and insulator (D) a material which has conductivity a having average value of conductivity of metal and insulator. B 134. Two resistors R1 = 47 kohm, 1 W and R2 = 0 ohm, 1 W are connected in parallel. The combined value will be (A) 47 kohm, 1 W (B) 47 kohm, 2W (C) 47 kohm, 1 / 2 W (D) 0 kohm, 1W. D 135. A rheostat differs from potentiometer in the respect that (A) rheostat has large number of turns (B) rheostat offers larger number of tappings (C) rheostat has lower wattage rating (D) rheostat has higher wattage ratings. D 136. The equivalent resistance at the points X1 and X2 in the circuit shown below

(A) 60 ohm (B) 40ohm (C) 80 ohm (D) 20ohm. B

137. For the same electrical resistance, the weight of aluminium conductor as compared to copper conductor of identical cross-section is (A) 85% (B) 50% (C) 20% (D) 120%. B 138. A drawn wire of resistance 25 ohm is further drawn so that its diameter becomes one fifth. Its resistance will now be (A) 625 ohm (B) 125 ohm (C) 25 ohm (D) 1 ohm. A 139. Which of the following has negative coefficient of resistance? (A) Wire wound resistor (B) Metals (C) Non-metals (D) Thermistor. D 140. The current at a given point in a certain circuit may be written as a function of time t, as i ( t ) = -3 + t. The total charge passing a point between t = 99 and t = 102 sec will be (A) 112 coulombs (B) 242.5 coulombs (C) 292.5 coulombs (D) 345.6 coulombs. C 143. A resistor has the value of 30 kohm and the current in it is measured to be 0.5 mA. The conductance is (A) 15 (B) 30000

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(C) 3.33 x 10-5 (D) 3.33 x 10-3 C 144. In the above problem, the terminal voltage must be (A) 15 mV (B) 1.5 V (C) 15 V (D) 150 V. C 145. The charge of an electron is known to be 1.6 x 10-19C. How many electron does not 1 make it C of charge ? (A) one (B) one million (C) 6.2 x 1018 (D) 1.6 x 10-19. C 151. A resistor has the value of 3 kohm and the current through it is measured to be 0.3 mA. The conductance is (A) 30000 mho (B) 30 mho (C) 0.33 milli mho (D) 30 micro mho. C 152. Resistance between X1 and X2 is

(A) 10 ohm (B) greater than 10 ohm (C) 0 (D) less than 10 ohm. C

153. When checked with an ohm meter an open resistor reads (A) zero (B) high but within tolerance (C) low but not zero (D) infinite. D 154. A current of 1 mA flows through a 1 Mohm, 2 W carbon resistor. The power dissipated as heat in the resistor will be (A) 2 W (B) 1 W (C) 0.5W (D) 0.1W. B 155. Which of the following carbon coded resistor has value of 10 kohm with 20% tolerance? (A) Red, red, green and silver stripes (B) Yellow, violet, yellow and silver stripes (C) Orange, orange, black and gold stripes (D) Brown, black, orange and no tolerance band. D 156. A carbon resistor has to meet the following requirements IR drop: 5 V, Current: 100 mA, Safety factor for power dissipation : 2. Which of the following resistors will be suitable ? (A) 5 ohm, 10 W (B) 0.5 ohm, 100 W (C) 5 ohm, 10 W (D) 50 ohm, 1 W. D 157. A 10 ohm resistor with a 10 W power rating is expected to be a (A) carbon resistor (B) wire wound resistor (C) either carbon or wire wound resistor (D) neither carbon nor wire wound resistor.

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B 158. Two 10 kohm, 5 W resistors in parallel have equivalent resistances of 5 kohm and power rating of (A) 2.5 W (B) 5 W (C) 10 W (D) 25 W. C 160. A 100 kohm resistor with a 1 W power rating is likely to be a

(A) carbon resistor (B) wire wound resistor (C) either carbon or wire wound resistor (D) neither carbon nor wire wound resistor. A 161. Two 5 kohm, 5 W resistors in series have equivalent resistance of 10 kohm with power rating of (A) 2.5 W (B) 5 W (C)10W (D) 25 W. C 162. Which of the following are typical resistance and power-dissipation values for a carbon- composition resistor ? (A) 10,000 ohm, 10 W (B) 1000,000 ohm, 1 W (C) 5000 ohm, 100 W (D) 10 ohm, 50 W. B 163. A resistor is to be connected across a 45 V battery to provide 1 mA of current. The required resistance with a suitable wattage rating is (A) 45 ohm, 10 W (B) 4.5 ohm, 2 W (C) 450 kohm, 2 W

(D) 45 kohm, 1/4 W. D 166. For a carbon-composition resistor color coded with green, black, gold and silver stripes from left to right, the resistance and tolerance are (A) 50 ohm ± 10% (B) 5 ohm ± 5% (C) 5 ohm ± 10% (D) 0.5 ohm ± 5%. C 167. A resistor with the color coded value of 1000 ohms and ± 10% tolerance can have an actual resistance between (A) 990 ohm and 1010 ohm (B)900 ohm and 1100 ohm (C)1000 ohm and 1100 ohm (D)900 ohm and 1000 ohm. B 168. For carbon resistors what is the color for 5? (A) Green (B) Black (C) Orange (D) Gray. A 169. For carbon resistors, darker colour generally have values close to (A) 1 (B) 5 (C) 8 (D) 9. A 170. In a carbon resistor in case fourth stripe is not present, it can be concluded that (A) the resistor is highly accurate (B) the resistor is defective (C) the resistor does not contain carbon

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(D) the tolerance limit is ± 20 %. D 171. The four stripes of a resistor are yellow-violet-orange-gold. The value of resistor should be (A) 470 ohms ± 5 % (B) 47 kilo ohm ± 5% (C) 47 mega ohms ± 5% (D) 4700 ohms ± 10%. B 172. The tolerance for silver stripe is (A)+5% (B)+ 10% (C)± 5% (D)± 10%. D 173. Which of the following can have positive or negative charge? (A) Electron (B) iron (C) Hole (D) Neutron. B 174. Which of the following parallel resistances will have the highest value of equivalent resistance? (A) 10 kohm and 25 kohm (B) 1 kohm, 2 kohm and 3 kohm (C) Two 500 kohm resistors (D) Four 40 kohm and two 10 kohm resistors. C 175. In series as well as parallel circuits the equivalent (total) value of certain parameter is given by X = X1 + X2 + X3 + X4 + ... The parameter X could be (A) resistance (B) current (C) voltage

(D) power. D 176. The resistance of a 150-scale voltmeter is 12000 ohms. The power consumed by the voltmeter when it is connected across a 125 volt circuit, will be nearly (A) 0.0013 W (B) 0.013 W (C) 0.13 W (D) 1.3 W. D 177. Materials having electrical conductivity much less than most of the metals but much greater than that of typical insulators, are known as (A) thermistors (B) varistors (C) semi-conductors (D) variable resistors. C 178. Match the following :

Column 1 Column 2

Copper Resistors

Salt Solution Electrolytic Conductor

Germanium Good Conductor

Ferronickel alloys Semi-Conductors

(A) a-(i), b-(ii), c-(iii), d(iv) (B) a-(ii), b(iii), c-(iv), d-(i) (C) a-(iiii),b-(i), c-(ii), d-(i) (D) a-(iii), b-(ii) c-(iv), d-(i). D 180. In a nickel-cadmium-alkali cell the electrolyte is (A) sulphur acid (B) potassium hydroxide (C) zinc chloride (D) ammonium chloride.

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B 181. Which value of resistance P shown in the circuit will allow 1080 Watts to be dissipated

(A) 19.5 ohms (B) 14.5 ohms (C) 9.75 ohms (D) 5.55 ohms. C