Interview Questions on Thermodynamics

1. Crude oil is the origin of all liquid fuel used commercially.
  1. True
  2. False

Answer:A

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2. Which process is responsible for transfer of mass to and from in an open system
  1. flow processes
  2. non-flow processes
  3. adiabatic processes
  4. none of these

Answer:A

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3. A cycle consisting of one constant pressure, one constant volume and two isentropic processes is known as
  1. Carnot cycle
  2. Stirling cycle
  3. Otto cycle
  4. Diesel cycle

Answer:D

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4. The change of entropy, when heat is removed from the gas, is positive.
  1. Yes
  2. No

Answer:B

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5. The ratio of root mean square velocity to average velocity of gas molecules at a particular temperature is
  1. 0.086
  2. 1.086
  3. 3.086
  4. 4.086

Answer:B

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6. Which of the following statement is incorrect?
  1. The liquid fuels consist of hydrocarbons.
  2. A good fuel should have low ignition point
  3. In general, the calorific value of solid fuels is always higher than liquid fuels
  4. None of the above

Answer:C

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7. The efficiency and work ratio of a simple gas turbine cycle are
  1. low
  2. very low
  3. high
  4. very high

Answer:B

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8. The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called
  1. specific heat at constant volume
  2. specific heat at constant pressure
  3. kilo Joule
  4. none of these

Answer:A

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9. Atomic mass is lowest in
  1. Oxygen
  2. Sulphur
  3. Nitrogen
  4. Carbon

Answer:D

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10. There is a loss of heat in an irreversible process.
  1. True
  2. False

Answer:A

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11. An adiabatic process is one in which
  1. no heat enters or leaves the gas
  2. the temperature of the gas changes
  3. there is no heat transfer into or out of system and change in internal energy is equal to the mechanical work-done
  4. all of the above

Answer:D

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12. Water gas is obtained by passing air and a large amount of steam over waste coal at about 650°C.
  1. Correct
  2. Incorrect

Answer:B

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13. When the heat transfer into a system is more than the work transfer out of the system, then
  1. the internal energy of the system remains same throughout
  2. the internal energy of the system decreases
  3. the internal energy of the system increases
  4. none of the above

Answer:C

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14. The boiler in which the tubes are surrounded by hot gases is called as
  1. fire tube boiler
  2. water tube boiler
  3. both a and b
  4. none of the above

Answer:B

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15. First law of thermodynamics provides
  1. that energy cannot be created or destroyed and conservation of energy take place when a system goes through the change of state
  2. whether the a change in state of a system is possible or not
  3. both a. and b.
  4. none of the above

Answer:A

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16. The thermodynamic cycle in which net heat is transferred to the system and a net work is transferred from the system is called as
  1. refrigeration cycle
  2. heat engine cycle
  3. both a. and b.
  4. none of the above

Answer:B

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17. Which of the following is NOT the heat engine cycle
  1. refrigerator
  2. stem power plant
  3. mass of gas confined in a cylinder and piston machine
  4. none of the above

Answer:A

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18. Practically heat and work are completely interchangeable forms of energy
  1. True
  2. False

Answer:B

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19. Efficiency of heat engine cycle is the ratio of
  1. total heat input to the cycle (Qin) to net work output of the cycle (Wnet)
  2. net work output of the cycle (Wnet) to total heat input to the cycle (Qin)
  3. net work output of the cycle (Wnet) to heat rejected from the system (Qout)
  4. none of the above

Answer:A

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20. A thermal energy reservoir (TER) has
  1. a finite heat capacity
  2. an infinite heat capacity
  3. a finite mass
  4. none of the above

Answer:B

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21. The term which can differentiate thermodynamics from other sciences is ____.
  1. Pressure
  2. Temperature
  3. Mass
  4. none of the above

Answer:B

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22. Two reversible adiabatic paths
  1. can intersect with each other
  2. cannot intersect with each other
  3. may intersect or may not intersect
  4. none of the above

Answer:B

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23. Which property of a system is constant in reversible adiabatic process?
  1. pressure
  2. volume
  3. temperature
  4. entropy

Answer:D

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24. Thermodynamics is the study of
  1. energy
  2. equilibrium
  3. entropy
  4. none of the above

Answer:D

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25. For a reversible process the cyclic integral of dQ/T is
  1. less than zero
  2. zero
  3. more than zero
  4. none of the above

Answer:B

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26. For a irreversible process the cyclic integral of dQ/T is
  1. less than zero
  2. zero
  3. more than zero
  4. none of the above

Answer:A

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27. A reversible path can be substituted by a reversible zigzag path between the same end processes if the heat transfer during this zigzag path is equal to the heat transfer during original path. Under such conditions what are processes involved in zigzag path
  1. reversible polytropic and isobaric process
  2. reversible polytropic and isothermal process
  3. reversible adiabatic and isothermal processes
  4. none of the above

Answer:C

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28. If you mix coal and gas at ambient condition then you would get coal gas
  1. Yes
  2. No

Answer:B

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29. How does the entropy changes if a system is taken from state A to state B thru a reversible path 1 and then back to its initial state A from B thru different reversible path 2
  1. entropy increases
  2. entropy decreases
  3. entropy remains constant
  4. none of the above

Answer:C

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30. What is the exergy of a system?
  1. It is the minimum useful work that can be extracted from a system to bring thermodynamic equilibrium with its surroundings
  2. It is the maximum useful work that can be extracted from a system to bring thermodynamic equilibrium with its surroundings
  3. It is the maximum entropy that can be increased in a system to bring thermodynamic equilibrium with its surroundings
  4. none of the above

Answer:B

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31. What is the effect on quality of the energy when it is conserved?
  1. Increases
  2. Decreases
  3. Remains Constant
  4. none of the above

Answer:B

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32. Which analysis is necessary to make energy conveying system more efficient?
  1. First law or energy analysis
  2. Second law or energy analysis
  3. Both a. and b.
  4. None of the above

Answer:C

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33. A pure substance exists in
  1. solid phase
  2. liquid phase
  3. gaseous phase
  4. all of the above

Answer:D

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34. What is a mole of a substance?
  1. 1 mole of mass is numerically equal to half the molecular weight of the substance
  2. 1 mole of mass is numerically equal to the molecular weight of the substance
  3. 1 mole of mass is numerically equal to double the molecular weight of the substance
  4. none of the above

Answer:B

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35. If mass of 1 kg mol of oxygen is 32 kg and mass of 1 kg mol of nitrogen is 28 kg then as per Avogadro's law what is relation between the two at STP (standard temperature & pressure)
  1. vol. of 1 kg mol of oxygen is > than that of nitrogen
  2. vol. of 1 kg mol of oxygen is < than that of nitrogen
  3. vol. of 1 kg mol of oxygen is = to that of nitrogen
  4. none of the above

Answer:C

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36. A single phase pure substance has following properties p, V, T, S, U, H, F (Helmholtz function) and G (Gibbs function). Any one in these properties may be expressed
  1. as a function of the same property
  2. as a function of any 1 other property
  3. as a function of any 2 other properties
  4. none of the above

Answer:C

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37. 1 kg of carbon requires 4/3 kg of oxygen to produce __________ kg of CO (carbon monoxide)
  1. 8/3
  2. 11/3
  3. 11/7
  4. 7/3

Answer:D

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38. Joule-Kelvin effect can be carried out by
  1. throttling process of gas
  2. Joule-Thomson expansion of gas
  3. both a. and b.
  4. none of the above

Answer:C

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39. What will be the net change in internal energy of working fluid of power cycle over the complete cycle?
  1. The net change in internal energy will be +ve for working fluid
  2. The net change in internal energy will be negative for working fluid
  3. There will not be any net change in internal energy of working fluid
  4. none of the above

Answer:C

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40. What happens to net energy transferred to a unit mass of working fluid as “heat” in power cycle and net energy transferred as “work” from the working fluid in same power cycle.(assume the cycle works ideally)
  1. The net energy transferred as heat in the power cycle is > than net energy transfer as work from the working fluid in the same power cycle
  2. The net energy transferred as heat in the power cycle is < than net energy transfer as work from the working fluid in the same power cycle
  3. The net energy transferred heat in the power cycle is equal to net energy transfer as work from the working fluid in the same power cycle
  4. cannot say

Answer:C

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41. What is the formula for efficiency of vapour power cycle?
  1. ηcycle = Wnet / Qin
  2. ηcycle = (WT – WP) / Qin
  3. ηcycle = (Qin – Qout) / Qin
  4. all of the above

Answer:D

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42. Which processes do the Rankine cycle contain?
  1. two isothermal and two isochoric processes
  2. two isentropic and two isobaric processes
  3. two isentropic and two isothermal processes
  4. two isothermal and two isobaric processes

Answer:B

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43. Where does the reversible constant pressure heat rejection carried out in an ideal vapour power cycle
  1. boiler
  2. turbine
  3. condenser
  4. feed pump

Answer:C

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44. Which reversible process happens in a turbine during vapour power cycle
  1. reversible adiabatic compression
  2. reversible adiabatic expansion
  3. reversible constant pressure heat addition
  4. reversible constant pressure heat rejection

Answer:D

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45. Internal combustion engine is the example of
  1. cyclic heat engine
  2. non-cyclic heat engine
  3. both a. and b.
  4. none of the above

Answer:B

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46. The cycle which consists of two reversible isotherms and two reversible isochores is called as
  1. Rankine cycle
  2. Carnot cycle
  3. Stirling cycle
  4. Ericsson cycle

Answer:C

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47. The pressure exerted by an ideal gas is __________ of the kinetic energy of all the molecules contained in a unit volume of gas.
  1. one-half
  2. one-third
  3. two-third
  4. three-fourth

Answer:C

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48. Which thermodynamic cycle, for the same condition, has highest efficiency among the others?
  1. Carnot cycle
  2. Stirling cycle
  3. Ericsson cycle
  4. None, All of the above have same efficiency

Answer:D

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49. What is the reason of the fact that the internal combustion engine does not complete thermodynamic cycle?
  1. because every time fresh air is taken inside the engine and combustion products are thrown out of the engine
  2. because permanent chemical change happens to working fluid in combustion chamber
  3. both a. and b.
  4. none of the above

Answer:C

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50. Where is main concentration in refrigeration for its calculation?
  1. high temperature reservoir
  2. low temperature reservoir
  3. both high temperature and low temperature reservoirs
  4. none of the above

Answer:B

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51. What is the relation between [COP]H. P. = [COP]Ref.?
  1. [COP]H. P. = [COP]Ref.
  2. [COP]H. P. + [COP]Ref. = 1
  3. [COP]H. P. – [COP]Ref. = 1
  4. [COP]H. P. × [COP]Ref. = 1

Answer:C

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52. What is the effect of decrease in temperature difference between two reservoirs of heat pump on its COP?
  1. The COP increases with decreases in temp diff between the 2 reservoirs
  2. The COP decreases with decreases in temp diff between the 2 reservoirs
  3. The COP does not affected by change in temp diff between the 2 reservoirs
  4. cannot say

Answer:A

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53. Dry air does NOT contain
  1. krypton
  2. argon
  3. neon
  4. none of the above

Answer:D

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54. The ratio of partial pressure of water vapour in a mixture to the saturation pressure of water at the same temperature of the mixture is called as
  1. humidity
  2. partial humidity
  3. specific humidity
  4. relative humidity

Answer:D

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55. All the commercial liquid fuels are derived from natural petroleum (or crude oil).
  1. True
  2. False

Answer:A

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56. A cycle consisting of one constant pressure, one constant volume and two isentropic processes is known as
  1. Carnot cycle
  2. Stirling cycle
  3. Otto cycle
  4. Diesel cycle

Answer:D

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57. The efficiency and work ratio of a simple gas turbine cycle are
  1. low
  2. very low
  3. high
  4. very high

Answer:B

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58. The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called
  1. specific heat at constant volume
  2. specific heat at constant pressure
  3. kilo Joule
  4. none of these

Answer:A

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59. There is a loss of heat in an irreversible process.
  1. True
  2. False

Answer:A

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60. An adiabatic process is one in which
  1. no heat enters or leaves the gas
  2. the temperature of the gas changes
  3. the change in internal energy is equal to the mechanical workdone
  4. all of the above

Answer:D

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61. Water gas is obtained by passing air and a large amount of steam over waste coal at about 650°C.
  1. Correct
  2. Incorrect

Answer:B

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62. When the gas is heated at constant volume, the heat supplied increases the internal energy of the gas.
  1. True
  2. False

Answer:A

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63. Which of the following is the lightest and most volatile liquid fuel?
  1. Gasoline
  2. Kerosene
  3. Fuel oil

Answer:A

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64. Workdone in a free expansion process is
  1. zero
  2. minimum
  3. maximum
  4. positive

Answer:A

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65. The compression ratio for petrol engines is
  1. 3 to 6
  2. 5 to 8
  3. 15 to 20
  4. 20 to 30

Answer:B

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66. The efficiency of Diesel cycle approaches to Otto cycle efficiency when
  1. cut-off is increased
  2. cut-off is decreased
  3. cut-off is zero
  4. cut-off is constant

Answer:C

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67. The entropy __________ in an irreversible cyclic process
  1. remains constant
  2. decreases
  3. increases

Answer:C

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68. The atomic mass of oxygen is
  1. 12
  2. 14
  3. 16
  4. 32

Answer:C

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69. The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is
  1. equal to one
  2. less than one
  3. greater than one
  4. none of these

Answer:C

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70. The energy of an isolated system
  1. is always decreasing
  2. is always constant
  3. is always increasing
  4. none of the above

Answer:B

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71. Thermodynamic work done by the system on its surrounding is considered as ____.
  1. positive
  2. negative
  3. neutral
  4. none of the above

Answer:A

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72. The efficiency of Stirling cycle is __________ Carnot cycle.
  1. greater than
  2. less than
  3. equal to

Answer:C

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73. According to Gay-Lussac law for a perfect gas, p/T = constant, if v is kept constant.
  1. True
  2. False

Answer:A

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74. There is no change in internal energy in an isothermal process.
  1. Correct
  2. Incorrect

Answer:A

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75. If the value of n = 0 in the equation pvn = C, then the process is called
  1. constant volume process
  2. adiabatic process
  3. constant pressure process
  4. isothermal process

Answer:C

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76. The value of specific heat at constant pressure (cp) is __________ that of at constant volume (cv).
  1. less than
  2. equal to
  3. more than

Answer:C

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77. When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.
  1. atomisation
  2. carbonisation

Answer:B

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78. Which of the following is correct?
  1. Absolute pressure = Gauge pressure + Atmospheric pressure
  2. Gauge pressure = Absolute pressure + Atmospheric pressure
  3. Atmospheric pressure = Absolute pressure + Gauge pressure
  4. Absolute pressure = Gauge pressure - Atmospheric pressure

Answer:A

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79. The distillation carried out in a manner that the liquid with the lowest boiling point is first evaporated and re-condensed, then the liquid with the next higher boiling point is then evaporated and re-condensed, and so on until all the available liquid fuels are separately recovered in the sequence of their boiling points. Such a process is called
  1. Cracking
  2. Carbonisation
  3. Fractional distillation
  4. Full distillation

Answer:C

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80. Which of the following gas is mostly used in town for street and domestic lighting and heating?
  1. Producer gas
  2. Coal gas
  3. Mond gas
  4. Coke oven gas

Answer:B

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81. The value of gas constant (R) in S. I. units is
  1. 0.287 J/kgK
  2. 2.87 J/kgK
  3. 28.7 J/kgK
  4. 287 J/kgK

Answer:D

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82. In the first law of thermodynamics, the total energy of the system remains constant.
  1. True
  2. False

Answer:A

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83. The efficiency of Diesel cycle increases with
  1. decrease in cut-off
  2. increase in cut-off
  3. constant cut-off
  4. none of these

Answer:A

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84. According to Avogadro's law, the density of any two gases is __________ their molecular masses, if the gases are at the same temperature and pressure.
  1. equal to
  2. directly proportional to
  3. inversely proportional to

Answer:B

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85. The kinetic energy of molecules of a gas becomes zero at absolute zero temperature
  1. Agree
  2. Disagree

Answer:A

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86. 1 kg of CO (carbon monoxide) needs __________ kg of oxygen to produce 11/7 kg of CO2
  1. All
  2. 4/7
  3. 11/4
  4. 9/7

Answer:B

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87. The absolute zero temperature is taken as
  1. -273°C
  2. 273°C
  3. 237°F
  4. -237°F

Answer:A

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88. The specific heat of water is
  1. 1.817
  2. 2512
  3. 4.187
  4. none of these

Answer:C

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89. Constant pressure, constant volume & constant pvn processes are considered as irreversible process.
  1. True
  2. False

Answer:A

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90. Stirling and Ericsson cycles are
  1. reversible cycles
  2. irreversible cycles
  3. semi-reversible cycles
  4. quasi-static cycles

Answer:A

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91. When cut-off ratio is __________ the efficiency of Diesel cycle approaches to Otto cycle efficiency.
  1. zero
  2. 1/5
  3. 4/5
  4. 1

Answer:A

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92. In which cycle out of below can we have series of operations done in a certain order and then restored to the initial conditions at the end
  1. reversible cycle
  2. irreversible cycle
  3. thermodynamic cycle
  4. none of these

Answer:C

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93. An isothermal process is governed by
  1. Boyle's law
  2. Charles' law
  3. Gay-Lussac law
  4. Avogadro's law

Answer:A

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94. The sum of internal energy (U) and the product of pressure and volume (p.v) is known as
  1. workdone
  2. entropy
  3. enthalpy
  4. none of these

Answer:C

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95. The value of 1 mm of Hg is equal to
  1. 1.333 N/m2
  2. 13.33 N/m2
  3. 133.3 N/m2
  4. 1333 N/m2

Answer:C

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96. Which law governs the behaviour of a perfect gas when it undergoes a change in the variables which control its physical properties
  1. Boyle's law
  2. Charles' law
  3. Gay-Lussac law
  4. all of these

Answer:D

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97. The universal gas constant of a gas is the product of molecular mass of the gas and the gas constant
  1. Correct
  2. Incorrect

Answer:A

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98. According to Kelvin-Planck's statement of second law of thermodynamics,
  1. it is not possible to create an engine operating on a cyclic process with a sole purpose of converting heat energy into work
  2. it is possible to create an engine operating on a cyclic process with a sole purpose of converting heat energy into work
  3. it is impossible to construct a device which operates in a cyclic process and produces no effect other than the transfer of heat from a cold body to a hot body
  4. none of the above

Answer:A

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99. If volume remains constant then as per Gay-Lussac law, the absolute pressure of a given mass of a perfect gas varies __________ as its absolute temperature.
  1. Directly
  2. Indirectly

Answer:A

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100. A process, in which the temperature of the working substance remains constant during its expansion or compression, is called
  1. isothermal process
  2. hyperbolic process
  3. adiabatic process
  4. polytropic process

Answer:A

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101. Which of the following gas has a minimum molecular mass?
  1. Oxygen
  2. Nitrogen
  3. Hydrogen
  4. Methane

Answer:C

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102. Which law states that the total energy of a molecule is shared equally by the various degrees of freedom possessed by it.
  1. law of equipartition of energy
  2. law of conservation of energy
  3. law of degradation of energy
  4. none of these

Answer:A

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103. The thermodynamic property of a system is said to be an intensive property whose value for the entire system __________ the sum of their value for the individual parts of the system.
  1. is equal to
  2. is not equal to

Answer:B

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104. The absolute pressure of a given mass of a perfect gas varies inversely as its volume, when the temperature remains constant. This statement is known as Charles' law.
  1. Yes
  2. No

Answer:B

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105. The fuel mostly used in steam boilers is
  1. brown coal
  2. peat
  3. coking bituminous coal
  4. non-coking bituminous coal

Answer:D

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106. The efficiency of Joule cycle is
  1. greater than Carnot cycle
  2. less than Carnot cycle
  3. equal to Carnot cycle
  4. none of these

Answer:B

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107. The hyperbolic pocess is governed by
  1. Boyle's law
  2. Charles' law
  3. Gay-Lussac law
  4. Avogadro's law

Answer:A

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108. In a closed system heat and work crosses the boundary of the system but not the mass of the working substance.
  1. Yes
  2. No

Answer:A

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109. The entropy of water at 0°C is assumed to be
  1. 1
  2. 0
  3. -1
  4. 10

Answer:B

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110. The greater the pressure difference in throttling, the lesser is the irreversibility.
  1. Yes
  2. No

Answer:B

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111. During which of the following process does heat rejection takes place in Carnot cycle?
  1. Isothermal expansion
  2. Isentropic expansion
  3. Isothermal compression
  4. Isentropic compression

Answer:C

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112. When two bodies are in thermal equilibrium with a third body, they are also in thermal equilibrium with each other. This statement is called
  1. Zeroth law of thermodynamics
  2. First law of thermodynamics
  3. Second law of thermodynamics
  4. Kelvin Planck's law

Answer:A

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113. The area under the temperature-entropy curve (T - s curve) of any thermodynamic process represents
  1. heat absorbed
  2. heat rejected
  3. either (a) or (b)
  4. none of these

Answer:C

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114. The free expansion process is a constant enthalpy process.
  1. Correct
  2. Incorrect

Answer:A

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115. Ericsson cycle has 2 constant pressure and 2 isothermal processes.
  1. Agree
  2. Disagree

Answer:A

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116. The isothermal and isentropic processes are reversible non-flow processes.
  1. Agree
  2. Disagree

Answer:A

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117. The blast furnace gas is a by-product in the production of pig iron in the blast furnace.
  1. Yes
  2. No

Answer:A

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118. The heat supplied to the gaS at constant volume is (where m = Mass of gas, cv = Specific heat at constant volume, cp = Specific heat at constant pressure, T2-T1=change in temperature, and R = Gas constant)
  1. mR(T2 - T1)
  2. mcv(T2 - T1)
  3. mcp(T2 - T1)
  4. mcp(T2 + T1)

Answer:B

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119. Liquid fuels have lower efficiency than solid fuels.
  1. True
  2. False

Answer:B

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120. Liquid fuels consist of hydrocarbons.
  1. True
  2. False

Answer:A

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121. Dual combustion cycle has 1 constant pressure, 2 constant volume and 2 isentropic processes.
  1. Agree
  2. Disagree

Answer:A

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122. The general gas energy equation is (where Q1 - 2 = Heat supplied, dU = Change in internal energy, and W1 - 2 = Work done in heat units)
  1. Q1 - 2 = dU + W1 – 2
  2. Q1 - 2 = dU - W1 – 2
  3. Q1 - 2 = dU/W1 – 2
  4. None of the above

Answer:A

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123. The compression ratio for Diesel engines is
  1. 3 to 6
  2. 5 to 8
  3. 15 to 20
  4. 20 to 30

Answer:C

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124. In an isothermal process,
  1. there is no change in temperature
  2. there is no change in enthalpy
  3. there is no change in internal energy
  4. all of these

Answer:D

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125. The heating and expanding of a gas is called thermodynamic system
  1. Yes
  2. No

Answer:B

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126. If the compression ratio and heat input remains same then the Otto cycle efficiency is > than Diesel cycle efficiency because in Otto cycle
  1. combustion is at constant volume
  2. expansion and compression are isentropic
  3. maximum temperature is higher
  4. heat rejection is lower

Answer:D

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127. Liquid fuels have higher calorific value than solid fuels.
  1. Yes
  2. No

Answer:A

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128. The free expansion process is __________ non-flow process.
  1. reversible
  2. irreversible

Answer:B

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129. The gas constant (R) is equal to the __________ of two specific heats
  1. Sum
  2. Difference
  3. Product
  4. Ratio

Answer:B

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130. Hydrogen is the __________ substance.
  1. Lightest
  2. Heaviest

Answer:A

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131. Otto cycle is also known as
  1. constant pressure cycle
  2. constant volume cycle
  3. constant temperature cycle
  4. constant temperature and pressure cycle

Answer:B

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132. For a perfect gas, according to Boyle's law (where p = Absolute pressure, v = Volume, and T = Absolute temperature)
  1. p v = constant, if T is kept constant
  2. v/T = constant, if p is kept constant
  3. p/T = constant, if v is kept constant
  4. T/p = constant, if v is kept constant

Answer:A

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133. Producer gas is obtained by
  1. partial combustion of coal+coke+anthracite coal in a mixed air steam blast
  2. carbonisation of bituminous coal
  3. passing steam over incandescent coke
  4. None of the above

Answer:A

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134. The efficiency of a dual combustion cycle __________ upon cut-off ratio.
  1. Depends
  2. does not depend

Answer:A

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135. The efficiency of Diesel cycle depends upon
  1. temperature limits
  2. pressure ratio
  3. compression ratio
  4. cut-off ratio and compression ratio

Answer:D

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136. Those substances which have so far not been resolved by any means into other substances of simpler form are called
  1. Elements
  2. Compounds
  3. Atoms
  4. Molecules

Answer:A

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137. The measurement of a thermodynamic property known as temperature is based on
  1. Zeroth law of thermodynamics
  2. First law of thermodynamics
  3. Second law of thermodynamics
  4. none of these

Answer:A

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138. Kelvin-Planck's law deals with
  1. conservation of work
  2. conservation of heat
  3. conversion of heat into work
  4. conversion of work into heat

Answer:C

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139. For the same compression ratio, the efficiency of dual combustion cycle is
  1. > than Diesel cycle and < than Otto cycle
  2. < than Diesel cycle and > than Otto cycle
  3. > than Diesel cycle
  4. < than Diesel cycle

Answer:A

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140. In an irreversible process, there is a
  1. loss of heat
  2. no loss of heat
  3. gain of heat
  4. no gain of heat

Answer:A

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141. The amount of heat required to raise the temperature of unit mass of a gas through one degree at constant pressure is called specific heat at constant pressure.
  1. True
  2. False

Answer:A

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142. The change of entropy, when heat is removed from the gas, is negative
  1. Yes
  2. No

Answer:A

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143. One Joule (J) is equal to
  1. 1 N-m
  2. 1 kN-m
  3. 10 N-m/s
  4. 10 kN-m/s

Answer:A

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144. In which process does the expansion or compression happens as per pvn = C
  1. isothermal process
  2. adiabatic process
  3. hyperbolic process
  4. polytropic process

Answer:D

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145. The entropy is a point function and thus it is a property of the same.
  1. Correct
  2. Incorrect

Answer:A

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146. State of a substance whose evaporation from its liquid state is complete, is called
  1. Vapour
  2. perfect gas
  3. Air
  4. Steam

Answer:B

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147. An open cycle gas turbine works on
  1. Carnot cycle
  2. Otto cycle
  3. Joule's cycle
  4. Stirling cycle

Answer:C

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148. The efficiency of Carnot cycle depends upon
  1. temperature limits
  2. pressure ratio
  3. volume compression ratio
  4. cut-off ratio and compression ratio

Answer:A

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149. The gas turbine cycle with regenerator improves
  1. thermal efficiency
  2. work ratio
  3. avoids pollution
  4. none of these

Answer:A

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150. Which out of below substance has the highest calorific value
  1. Peat
  2. Lignite
  3. Bituminous coal
  4. Anthracite coal

Answer:A

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151. What changes out of the below options, when a gas is heated
  1. Pressure
  2. Volume
  3. Temperature
  4. all of these

Answer:D

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152. Which of the following is an intensive property of a thermodynamic system?
  1. Volume
  2. Temperature
  3. Mass
  4. Energy

Answer:B

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153. A triatomic molecule consists of __________ atoms
  1. One
  2. Two
  3. Three
  4. Four

Answer:C

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154. The main cause for the irreversibility is
  1. mechanical and fluid friction
  2. unrestricted expansion
  3. heat transfer with a finite temperature difference
  4. all of the above

Answer:D

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155. The cycle which has __________ and two isothermal processes is called Stirling cycle.
  1. two constant pressure
  2. two constant volume
  3. two isentropic
  4. one constant pressure, one constant volume

Answer:B

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156. Who proved that the heat and mechanical energies are mutually convertible
  1. Boyle
  2. Charles
  3. Joule
  4. none of these

Answer:C

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157. For the same compression ratio, the efficiency of Diesel cycle is __________ Otto cycle.
  1. greater than
  2. less than
  3. equal to

Answer:B

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158. Mond gas is obtained by
  1. partial combusion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
  2. carbonisation of bituminous coal
  3. passing steam over incandescent coke
  4. when air and a large amount of steam is passed over waste coal around 650°C

Answer:D

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159. The natural solid fuel is
  1. Wood
  2. Coke
  3. anthracite coal
  4. pulverised coal

Answer:A

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160. In open cycle gas turbine plants
  1. the indirect heat exchanger and cooler is avoided
  2. direct combustion system is used
  3. a condenser is used
  4. all of the above

Answer:D

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161. In an isolated system, neither the heat and work nor the, mass of the working substance crosses the boundary of the system.
  1. True
  2. False

Answer:A

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162. The compression ratio is the ratio of
  1. swept volume to total volume
  2. total volume to swept volume
  3. swept volume to clearance volume
  4. total volume to clearance volume

Answer:D

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163. When a fluid is allowed to expand suddenly into a vaccum chamber through an orifice of large dimensions, the process is known as free expansion process.
  1. True
  2. False

Answer:A

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164. Which of the following is the correct statement?
  1. All the reversible engines have the same efficiency.
  2. All the reversible & irreversible engines have exactly the same efficiency.
  3. Irreversible engines have maximum efficiency.
  4. None of the above

Answer:C

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165. A close cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine.
  1. Same
  2. Lower
  3. Higher

Answer:C

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166. The efficiency of Ericsson cycle is __________ Carnot cycle
  1. greater than
  2. less than
  3. equal to

Answer:C

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167. 1 molecule of oxygen has __________ atoms of oxygen.
  1. 2
  2. 4
  3. 8
  4. 16

Answer:A

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168. According to kinetic theory of gases, the velocity of molecules __________ with the increase in temperature.
  1. remains constant
  2. Increases
  3. Decreases

Answer:B

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169. Hard coke is formed when carbonisation of coal is carried out at
  1. 300° to 500°C
  2. 500° to700°C
  3. 700° to 900°C
  4. 900° to 1100°C

Answer:D

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170. Stirling cycle consists of
  1. two constant volume and two isentropic processes
  2. two constant volume and two isothermal processes
  3. two constant pressure and two isothermal processes
  4. None of the above

Answer:B

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171. The ratio of molar specific heats for monoatomic gas is
  1. 1
  2. 1.4
  3. 1.67
  4. 1.87

Answer:C

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172. The general law of expansion or compression is pvn = C, The process is said to be hyperbolic, if n is equal to
  1. 0
  2. 1
  3. Γ

Answer:B

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173. State of a substance whose evaporation from its liquid state is not complete ie it is partial, is known as steam
  1. Agree
  2. Disagree

Answer:B

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174. The value of universal gas constant is same for all gases.
  1. Yes
  2. No

Answer:A

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175. The numerical value of the thermal capacity and the water equivalent of the substance are the same.
  1. Agree
  2. Disagree

Answer:A

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176. The area under the temperature-entropy curve (i. e. T - s curve) of any thermodynamic process represents the workdone during the process.
  1. Agree
  2. Disagree

Answer:B

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177. The heating of a gas at constant pressure is governed by Charles' law.
  1. True
  2. False

Answer:A

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178. Carnot cycle consists of
  1. two constant volume and two isentropic processes
  2. two isothermal and two isentropic processes
  3. two constant pressure and two isentropic processes
  4. one constant volume, one constant pressure and two isentropic processes

Answer:B

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179. When a gas is heated at constant volume
  1. its temperature will increase
  2. its pressure will increase
  3. both temperature and pressure will increase
  4. neither temperature nor pressure will increase

Answer:C

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180. According to kinetic theory of gases, the kinetic energy of translation of a molecule is proportional to
  1. T
  2. 2T
  3. 1/T
  4. 2/T

Answer:A

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181. The amount of heat given out by the complete combustion of 1 kg of fuel is known as calorific value of solid or liquid fuel.
  1. True
  2. False

Answer:A

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182. The conditions of temperature and pressure at 0°C (273K) and 760 mm of Hg pressure are termed as __________ temperature and pressure.
  1. Normal
  2. Standard

Answer:B

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183. The value of cp/cv for air is
  1. 1
  2. 1.4
  3. 1.8
  4. 23

Answer:B

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184. The heat absorbed or rejected by the working substance is given by (where ds = Increase or decrease of entropy, T= Absolute temperature, and dQ = Heat absorbed or rejected)
  1. δQ = T.ds
  2. δQ = T/ds
  3. dQ = ds/T
  4. none of these

Answer:A

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185. Which of the following gas has the highest calorific value?
  1. Coal gas
  2. Producer gas
  3. Mond gas
  4. Blast furnace gas

Answer:A

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186. By how many times is the oxygen atom heavier than the hydrogen atom.
  1. 2
  2. 4
  3. 8
  4. 16

Answer:D

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187. When the gas is cooled at constant pressure,
  1. its temperature increases but volume decreases
  2. its volume increases but temperature decreases
  3. both temperature and volume increases
  4. both temperature and volume decreases

Answer:D

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188. As per Charles' law, the volume of a given mass of a perfect gas varies __________ as its absolute temperature, when the absolute pressure remains constant.
  1. Directly
  2. Indirectly

Answer:A

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189. The principal constituents of a fuel are
  1. carbon and hydrogen
  2. oxygen and hydrogen
  3. sulphur and oxygen
  4. sulphur and hydrogen

Answer:A

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190. In an extensive property of a thermodynamic system
  1. extensive heat is transferred
  2. extensive work is done
  3. extensive energy is utilised
  4. none of these

Answer:D

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191. When a gas is heated at constant pressure
  1. its temperature will increase
  2. its volume will increase
  3. both temperature and volume will increase
  4. neither temperature not volume will increase

Answer:C

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192. By decreasing the highest temperature in the Carnot cycle, its efficiency is increased.
  1. True
  2. False

Answer:B

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193. The lower calorific value of fuel may be obtained by adding the heat of steam formed during combustion to the higher calorific value.
  1. Yes
  2. No

Answer:B

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194. 1 kg of CO (carbon monoxide) requires 4/7 kg of oxygen and to produce
  1. 11/3 kg of carbon dioxide gas
  2. 7/3 kg of carbon monoxide gas
  3. 11/7 kg of carbon dioxide gas
  4. 8/3 kg of carbon monoxide gas

Answer:C

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195. The molecular mass expressed in gram (i.e. 1g - mole) of all gases, at S. T. P., occupies a volume of
  1. 0.224 litres
  2. 2.24 litres
  3. 22.4 litres
  4. 224 litres

Answer:C

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196. The absolute zero pressure will be
  1. when molecular momentum of the system becomes zero
  2. at sea level
  3. at the temperature of - 273 K
  4. at the centre of the earth

Answer:A

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197. The gas in cooling chamber of a closed cycle gas turbine is cooled at
  1. constant volume
  2. constant temperature
  3. constant pressure
  4. none of these

Answer:C

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198. The temperature at which the volume of a gas becomes zero is called
  1. absolute scale of temperature
  2. absolute zero temperature
  3. absolute temperature
  4. none of these

Answer:B

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199. Which law governs the heating of gas at constant volume
  1. Boyle's law
  2. Charles' law
  3. Gay-Lussac law
  4. Avogadro's law

Answer:C

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200. The absolute pressure of a given mass of a perfect gas varies inversely as its volume, when the temperature remains constant. This statement is known as Boyle's law.
  1. Yes
  2. No

Answer:A

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201. Which out of the below substance is mostly used in cement industry and in metallurgical processes
  1. wood charcoal
  2. bituminous coke
  3. pulverised coal
  4. Coke

Answer:A

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202. Boyle's law states that change of internal energy of a perfect gas is directly proportional to the change of temperature.
  1. Agree
  2. Disagree

Answer:B

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203. The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is always __________ one.
  1. equal to
  2. less than
  3. greater than

Answer:C

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204. The isothermal and adiabatic processes are regarded as
  1. reversible process
  2. irreversible process
  3. reversible or irreversible process
  4. none of these

Answer:A

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205. The variables which control the physical properties of a perfect gas are
  1. pressure exerted by the gas
  2. volume occupied by the gas
  3. temperature of the gas
  4. all of these

Answer:D

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206. The heat flows from a cold body to a hot body with the aid of an external source. This statement is given by
  1. Kelvin
  2. Joule
  3. Clausis
  4. Gay-Lussac

Answer:C

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207. The unit of power in S.I. units is kilowatt.
  1. True
  2. False

Answer:A

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208. Otto cycle consists of
  1. two constant volume and two isentropic processes
  2. two constant pressure and two isentropic processes
  3. two constant volume and two isothermal processes
  4. None of the above

Answer:A

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209. The increase in entropy of a system represents
  1. increase in availability of energy
  2. increase in temperature
  3. decrease in pressure
  4. degradation of energy

Answer:D

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210. In a free expansion process
  1. W1 - 2 = 0
  2. Q1 - 2 = 0
  3. dU = 0
  4. all of these

Answer:D

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211. The reading of the pressure gauge fitted on a vessel is 25 bar. What would be the absolute pressure in the vessel if the atmospheric pressure is 1.03 bar (g= 9.81 m/s2)
  1. 23.97 bar
  2. 25 bar
  3. 26.03 bar
  4. 34.81 bar

Answer:C

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212. The general gas equation is (where p = Pressure, v = Volume, m = mass, T = Absolute temperature, and R = Gas constant)
  1. pv = Mrt
  2. pv = RTm
  3. pvm = C
  4. pv = (RT)m

Answer:A

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213. The work ratio of simple gas turbine cycle depends upon
  1. maximum cycle temperature
  2. minimum cycle temperature
  3. pressure ratio
  4. all of these

Answer:D

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214. The gas constant (R) is equal to the
  1. sum of two specific heats
  2. difference of two specific heats
  3. product of two specific heats
  4. ratio of two specific heats

Answer:B

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215. One kg of hydrogen requires 8 kg of oxygen and produces
  1. 1 kg of water
  2. 7 kg of water
  3. 8 kg of water
  4. 9 kg of water

Answer:D

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216. What is the standard value of atmospheric pressure measured at sea level
  1. 1.013 bar
  2. 760 mm of Hg
  3. 1013 x 102 N/m2
  4. all of these

Answer:D

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217. The efficiency of Otto cycle depends upon the specific heats of the working substance.
  1. Yes
  2. No

Answer:B

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218. The smallest quantity of a substance, which can exist by itself in a chemically recognizable form is known as
  1. Element
  2. Compound
  3. Atom
  4. Molecule

Answer:D

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219. The absolute zero pressure can be attained at a temperature of
  1. 0°C
  2. 273°C
  3. 273 K
  4. none of these

Answer:D

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220. 1 kg of ethylene (C2H4) needs 2 kg of oxygen to produce 22/7 kg of carbon dioxide and __________ kg of water or steam.
  1. 9/7
  2. 11/7
  3. 7/4
  4. 11/4

Answer:A

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221. One m3 of methane (CH4) requires 2m3 of oxygen and produces 1m3 of carbon dioxide and 2m3 of water or steam.
  1. Correct
  2. Incorrect

Answer:A

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222. Coke oven gas is obtained by burning coke in an oven.
  1. Agree
  2. Disagree

Answer:B

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223. A perpetual motion machine of the first kind is __________ according to first law of thermodynamics.
  1. Possible
  2. Impossible

Answer:B

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224. One kg of carbon requires 8/3 kg of oxygen for its complete combustion and produces 11/3 kg of carbon dioxide gas.
  1. Agree
  2. Disagree

Answer:A

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225. A process, in which the gas is heated or expanded in such a way that product of its pressure and volume remains constant, is called isothermal process.
  1. Yes
  2. No

Answer:B

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226. One reversible heat engine operates between 1600 K and T2 K and another reversible heat engine operates between T2 K and 400 K. If both the engines have the same heat input and output, then temperature T2 is equal to
  1. 800K
  2. 1000K
  3. 1200K
  4. 1400K

Answer:A

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227. When the gas is heated at constant volume, the heat supplied
  1. will result in increase in internal energy and temperature of the gas
  2. does some external work during expansion
  3. Both (A) and (B)
  4. None of these

Answer:A

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228. Equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules. This statement is called Avogadro's law.
  1. True
  2. False

Answer:A

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229. Wood charcoal is produced by heating the wood at 100°C.
  1. Yes
  2. No

Answer:B

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230. The __________ is obtained when carbonisation of coal is carried out at 500° to 700° C.
  1. soft coke
  2. hard coke
  3. pulverised coal
  4. bituminous coal

Answer:A

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231. In closed cycle gas turbine, the air is compressed
  1. Isothermally
  2. Isentropically
  3. Polytropically
  4. none of these

Answer:B

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232. For the same maximum pressure and temperature,
  1. Otto cycle is more efficient than Diesel cycle
  2. Diesel cycle is more efficient than Otto cycle
  3. Dual cycle is more efficient than both Otto & Diesel cycles
  4. None of the above

Answer:B

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233. In a steady flow process, the ratio of
  1. heat transfer is constant
  2. work transfer is constant
  3. mass flow at inlet and outlet is same
  4. all of these

Answer:D

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234. The entropy of the universe is continually on the increase.
  1. Correct
  2. Incorrect

Answer:A

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235. Select the correct statement as per Charles' law
  1. p.v = constant, if T is kept constant
  2. v/T = constant, if p is kept constant
  3. p/T = constant, if v is kept constant
  4. T/p = constant, if v is kept constant

Answer:B

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236. The unit of energy is S. I. units is
  1. Joule (J)
  2. Joule metre (Jm)
  3. Watt(W)
  4. Joule/metre (J/m)

Answer:A

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237. A process, in which the gas is heated or expanded in such a way that the product of its pressure and volume remains constant, is called
  1. isothermal process
  2. hyperbolic process
  3. adiabatic process
  4. polytropic process

Answer:B

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238. Diesel cycle consists of __________ processes
  1. two constant volume and two isentropic
  2. two constant pressure and two isentropic
  3. two constant volume and two isothermal
  4. 1 constant pressure, 1 constant volume and 2 isentropic

Answer:D

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239. If coal is first dried and then crushed to a fine powder using a pulverising machine, then the resulting substance is called
  1. wood charcoal
  2. bituminous coal
  3. briquetted coal
  4. none of these

Answer:D

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240. What would be value of “n” in the equation pvn = C in a adiabatic process
  1. 0
  2. 1
  3. Γ

Answer:C

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241. The molecular mass of a substance is the number of times a molecule of that substance is heavier than the hydrogen atom.
  1. True
  2. False

Answer:A

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242. The behaviour of super-heated vapour is similar to that of
  1. perfect gas
  2. Air
  3. Steam
  4. ordinary gas

Answer:A

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243. Briquetted coal is produced from the finely ground coal by moulding under pressure with or without a binding material.
  1. True
  2. False

Answer:A

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244. Which of the following is a reversible non-flow process?
  1. Isochoric process
  2. Isobaric process
  3. Hyperbolic process
  4. all of these

Answer:D

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245. If in the equation pvn = C, the value of n = ∝ , then the process is called
  1. constant volume process
  2. adiabatic process
  3. constant pressure process
  4. isothermal process

Answer:A

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246. The property of the system, whose value for the entire system is equal to the sum of their values for the individual parts of the system is called extensive property
  1. Yes
  2. No

Answer:A

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247. Coal gas consists mainly of hydrogen, carbon monoxide and various hydrocarbons.
  1. Agree
  2. Disagree

Answer:A

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248. High air-fuel ratio in gas turbines
  1. increases power output
  2. improves thermal efficiency
  3. reduces exhaust temperature
  4. do not damage turbine blades

Answer:A

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249. When the finely ground coal is moulded under pressure with or without a binding material, the resulting fuel is called briquetted coal.
  1. Yes
  2. No

Answer:A

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250. What will be the order of air standard efficiency of gas power cycle at constant pressure and heat input
  1. Dual cycle, Diesel cycle, Otto cycle
  2. Otto cycle, Diesel cycle, Dual cycle
  3. Dual cycle, Otto cycle, Diesel cycle
  4. Diesel cycle, Otto cycle, Dual cycle

Answer:A

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251. The elements are made up of minute and chemically invisible particles as atoms.
  1. True
  2. False

Answer:A

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252. All perfect gases change in volume by 1 / 273th of its original volume at 0°C for every 1°C change in temperature, when the pressure remains constant. This statement is called
  1. Boyle's law
  2. Charles' law
  3. Gay-Lussac law
  4. Joule's law

Answer:B

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253. A good fuel should have __________ ignition point
  1. High
  2. Low

Answer:B

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254. According to Kelvin-Planck's statement, a perpetual motion of the __________ is impossible
  1. first kind
  2. second kind

Answer:B

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255. The amount of heat generated per kg of fuel is known as
  1. calorific value
  2. heat energy
  3. lower calorific value
  4. higher calorific value

Answer:A

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256. Carnot cycle has maximum efficiency for
  1. petrol engine
  2. diesel engine
  3. reversible engine
  4. irreversible engine

Answer:C

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257. The entropy can be expressed as a function of
  1. pressure and temperature
  2. temperature and volume
  3. heat and work
  4. all of these

Answer:A

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258. It is __________ to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work.
  1. Possible
  2. Impossible

Answer:B

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259. Charles' law states that all perfect gases change in volume by __________ of its original volume at 0° C for every 1° C change in temperature, when pressure remains constant.
  1. 1/27th
  2. 1/93th
  3. 1/173th
  4. 1/273th

Answer:D

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260. The calorific value of gaseous fuel is expressed in
  1. kJ
  2. kJ/kg
  3. kJ/m2
  4. kJ/m3

Answer:A

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261. The throttling process is an irreversible steady flow expansion process.
  1. Correct
  2. Incorrect

Answer:A

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262. The efficiency of the dual combustion cycle for the same compression ratio, is __________ Diesel cycle.
  1. greater than
  2. less than
  3. equal to

Answer:A

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263. To ensure complete and rapid combustion of a fuel, some quantity of air, in excess of the theoretical or minimum air is supplied.
  1. Yes
  2. No

Answer:A

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264. According to Regnault's law, the specific heat at constant pressure (cp) and specific heat at constant volume (cv) __________ with the change in pressure and temperature of the gas.
  1. Change
  2. do not change

Answer:B

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265. The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
  1. Zeroth
  2. First
  3. Second

Answer:B

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266. Kerosene is distilled at
  1. 65° to 220°C
  2. 220° to 345°C
  3. 345° to 470°C
  4. 470° to 550°C

Answer:B

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267. The amount of heat obtained by the complete combustion of 1 kg of a fuel when the products of its combustion are cooled down to the temperature of supplied air is called __________ calorific value offuel
  1. Higher
  2. Lower

Answer:A

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268. The bomb calorimeter is used for finding the __________ calorific value of solid and liquid fuels.
  1. Higher
  2. Lower

Answer:A

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269. The efficiency of the Carnot cycle may be increased by
  1. increasing the highest temperature
  2. decreasing the highest temperature
  3. increasing the lowest temperature
  4. keeping the lowest temperature constant

Answer:A

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270. The atomic mass of sulphur is
  1. 12
  2. 14
  3. 16
  4. 32

Answer:D

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271. The atomic mass of an element is the number of times the atom of that element is heavier than the hydrogen atom.
  1. True
  2. False

Answer:A

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272. A cycle consisting of 2 isothermal and 2 isentropic processes, is called
  1. Carnot cycle
  2. Stirling cycle
  3. Ericsson cycle
  4. Joule cycle

Answer:A

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273. In an ideal gas turbine plant, it is assumed that the compression and expansion processes are
  1. Isothermal
  2. Isentropic
  3. Polytropic
  4. none of these

Answer:B

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274. When gas is heated at constant pressure, the heat supplied is utilised in
  1. increasing the internal energy of gas
  2. doing some external work
  3. increasing the internal energy of gas & for doing some external work
  4. none of the above

Answer:C

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275. The amount of heat required to raise the temperature of 1 kg of water through one Kelvin is called
  1. specific heat at constant volume
  2. specific heat at constant pressure
  3. kilo-Joule
  4. none of these

Answer:C

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276. When wood is heated with a limited supply of air to a temperature not less than 280°C, the resulting fuel is
  1. Coke
  2. wood charcoal
  3. bituminous coal
  4. briquetted coal

Answer:B

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277. The efficiency of Diesel cycle increases with increase in cut-off.
  1. Yes
  2. No

Answer:B

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278. The property of a working substance which increases or decreases as the heat is supplied or removed in a reversible manner, is known as
  1. Enthalpy
  2. internal energy
  3. Entropy
  4. external energy

Answer:C

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279. It is __________ to make an engine working on a Carnot cycle.
  1. Possible
  2. Impossible

Answer:B

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280. Reversed Joule cycle is known as
  1. Carnot cycle
  2. Bell-Coleman cycle
  3. Rankine cycle
  4. Stirling cycle

Answer:B

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281. Which of the following is the extensive property of a thermodynamic system?
  1. Pressure
  2. Volume
  3. Temperature
  4. Density

Answer:B

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282. It is impossible to transfer heat from a body at a lower temperature to a body at a higher temperature, without the aid of an external source.
  1. Correct
  2. Incorrect

Answer:A

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283. One kilowatt is equal to
  1. 1 N-m/s
  2. 100 N-m
  3. 1000 N-m/s
  4. 1 x 106 N-m/s

Answer:C

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284. Second law of thermodynamics defines
  1. Heat
  2. Work
  3. internal energy
  4. Entropy

Answer:D

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285. Energy can neither be created nor destroyed, but it can be transformed from one form to another. This statement is known as
  1. Zeroth law of thermodynamics
  2. First law of thermodynamics
  3. Second law of thermodynamics
  4. Kinetic theory of gases

Answer:B

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286. The value of one bar (in S. I. units) is equal to
  1. 1 x 102 N/m2
  2. 1 x 103 N/m2

Answer:D

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287. Petrol is distilled at
  1. 65° to 220°C
  2. 220° to 345°C
  3. 345° to 470°C
  4. 470° to 550°C

Answer:A

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288. If the carbon content in the bituminous coal is 78 – 81 percent, then it is called coking bituminous coal.
  1. Agree
  2. Disagree

Answer:B

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289. When a perfect gas is expanded through an aperture of minute dimensions, the process is known as
  1. isothermal process
  2. adiabatic process
  3. free expansion process
  4. throttling process

Answer:D

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290. Steam coal is a
  1. pulverised coal
  2. brown coal
  3. coking bituminous coal
  4. non-coking bituminous coal

Answer:D

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291. The kinetic energy per kg molecule of any gas at absolute temperature T is equal to (where Ru = Universal gas constant)
  1. Ru x T
  2. 1.5 Ru x T
  3. 2 Ru x T
  4. 3 Ru x T

Answer:B

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292. The atomic mass of nitrogen is __________ oxygen.
  1. equal to
  2. less than
  3. more than

Answer:B

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293. One kg of sulphur requires 1 kg of oxygen for complete combustion and produces 2 kg of sulphur dioxide.
  1. True
  2. False

Answer:A

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294. The change of entropy, when heat is absorbed by the gas, is
  1. Positive
  2. Positive
  3. positive or negative

Answer:A

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295. A machine which violates the first law of thermodynamics is known as perpetual motion machine of the second kind.
  1. Correct
  2. Incorrect

Answer:B

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296. The Ericsson and Joule's cycles have 2 constant pressure processes.
  1. True
  2. False

Answer:A

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297. The general law for the expansion or compression of gases, is
  1. pv = C
  2. pv = m R T

Answer:C

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298. The heat energy stored in the gas and used for raising the temperature of the gas is known as
  1. external energy
  2. internal energy
  3. kinetic energy
  4. molecular energy

Answer:B

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299. A cycle consisting of two constant pressure and two isentropic processes is known as
  1. Carnot cycle
  2. Stirling cycle
  3. Otto cycle
  4. none of these

Answer:D

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300. When the gas is heated at constant pressure, the heat supplied
  1. increases the internal energy of the gas
  2. increases the temperature of the gas
  3. does some external work during expansion
  4. Both (B) and (C)

Answer:D

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301. The __________ states that change of internal energy of a perfect gas is directly proportional to the change of temperature.
  1. Boyle's law
  2. Charle's law
  3. Gay-Lussac law
  4. Joule's law

Answer:D

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302. A closed cycle gas turbine works on Joule's cycle.
  1. True
  2. False

Answer:A

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303. The workdone in a free expansion process is zero.
  1. True
  2. False

Answer:A

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304. When a system changes its state from one equilibrium state to another equilibrium state, then the path of successive states through which the system has passed, is known as
  1. thermodynamic law
  2. thermodynamic process
  3. thermodynamic cycle
  4. none of these

Answer:B

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305. The fuel mostly used in blast furnace for extracting pig iron from iron ores is
  1. hard coke
  2. soft coke
  3. pulverised coal
  4. bituminous coal

Answer:A

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306. The ultimate analysis of coal consists of the determination of the percentage of
  1. Carbon
  2. hydrogen and nitrogen
  3. sulphur and ash
  4. all of these

Answer:D

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307. First law of thermodynamics deals with
  1. conservation of heat
  2. conservation of momentum
  3. conservation of mass
  4. conservation of energy

Answer:D

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308. The throttling process is __________ process.
  1. Reversible
  2. Irreversible
  3. reversible or irreversible

Answer:B

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309. A cycle consisting of two constant pressure and two isothermal processes is known as Ericsson cycle.
  1. True
  2. False

Answer:A

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310. A process of heating crude oil to a high temperature under a very high pressure to increase the yield of lighter distillates, is known as
  1. Cracking
  2. Carbonisation
  3. fractional distillation
  4. full distillation

Answer:A

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311. If in the equation pvn = C, the value of n = 1, then the process is called isothermal process.
  1. True
  2. False

Answer:A

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312. The specific volume of a system is an __________ property.
  1. Extensive
  2. Intensive

Answer:B

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313. Which of the following process can be made reversible with the help of a regenerator?
  1. Constant pressure process
  2. Constant volume process
  3. Constant pvn process
  4. all of these

Answer:D

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314. The ideal efficiency of simple gas turbine cycle depends upon pressure ratio.
  1. Yes
  2. No

Answer:A

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315. A molecule consisting of one atom is known as
  1. Monoatomic
  2. Diatomic
  3. Triatomic
  4. Polyatomic

Answer:A

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316. The natural petroleum may be separated into
  1. Petrol
  2. Kerosene
  3. fuel oil
  4. lubricating oil

Answer:D

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317. A definite area or a space where some thermodynamic process takes place is known as
  1. thermodynamic system
  2. thermodynamic cycle
  3. thermodynamic process
  4. thermodynamic law

Answer:A

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318. The amount of heat required to raise the temperature of __________ water through one degree is called kilojoule.
  1. 1 g
  2. 10 g
  3. 100 g
  4. 1000 g

Answer:D

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319. The 2 reversible isothermal processes and 2 reversible isobaric processes are carried out which cycle
  1. Rankine cycle
  2. Carnot cycle
  3. Stirling cycle
  4. Ericsson cycle

Answer:D

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