Laws of Thermodynamics| Part 2| MCQ

Laws of Thermodynamics

1. At absolute zero pressure…..

1. Molecular momentum of system becomes zero

2. Is pressure at sea level

3. Is measured at -273 k

4. Is measured at the center of the earth

2. An open system in one which ……

1. Heat and work cross the boundary of system but mass does not

2. Mass crosses boundary but heat and work do not

3. Heat ,work and/or mass cross boundary

4. Neither heat nor work nor mass crosses the boundary

3. A system comprising a single phase is called

1. Open system

2. Homogeneous system

3. Aqueous system

4. Heterogeneous system

4. 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

5. Which of the following is not a condition for the reversibility of a cycle is……

1. No appreciable pressure and temperature difference between system and surroundings

2. All processes must be extremely slow

3. Work part must be friction free

4. Very small loss of energy during the process

6. A thermometer works on…..

1. Zeroth law of thermodynamics

2. First law of thermodynamics

3. Second law of thermodynamics

4. Third law of thermodynamics

7. The heating and expansion of gas is called …..

1. Thermodynamics system

2. Thermodynamics law

3. Thermodynamics process

4. Thermodynamics cycle

8. Which of the following is extensive property

1. Volume

2. Specific volume

3. Temperature

4. Density

9. From an isolated system……

1. Transfer of energy and/or make take place

2. Transfer of only energy and not mass take place

3. Transfer of only mass and energy take place

4. Transfer of neither mass nor energy takes place

10. …….is incentive property of a thermodynamic system

1. Volume

2. Energy

3. Temperature

4. Mass

11. The temperature at which  volume of gas becomes zero is…….

1. Absolute scale of temperature

2. Absolute zero temperature

3. Absolute temperature

4. None of these

12. A fixed area or space where some thermodynamic process takes place is……

1. Thermodynamic process

2. Thermodynamic law 

3. Thermodynamic cycle 

4. Thermodynamic system

13. One watt is equal to……

1. 1 Nm/s

2. 1 Nm/s

3. 1Nm/min

4. 1N/s

14. A series of operations which takes place in a certain order and restores the initial condition is known as……

1. Thermodynamic cycle

2. Reversible cycle

3. Irreversible cycle

4. None of these

15. Which of the following is correct?

1. Gauge pressure=absolute pressure + atmospheric pressure

2. Absolute pressure=gauge pressure + atmospheric pressure

3. Atmospheric pressure = gauge pressure + absolute pressure

4. Gauge = atmospheric pressure + absolute pressure

16. 1 bar =……

1. 1N/m²

2. 1000N/m²

3. 10-3N/m²

4. 10²N/m²

17. Unit of energy is…….

1. Joule

2. Watt

3. Joule/meter

4. Joule meter

18. 1 joule=……

1. 1 watt/sec

2. 1 watt sec

3. 1N/s

4. 1N.m

19. Which of the following set has all incentive properties   ?        

1. Pressure, volume, energy, heat, specific volume

2. Pressure, temperature, density specific volume

3. Pressure, temperature, heat, mass 

4. Pressure, temperature, density, volume

20.  Which of the following sets has all open systems?

1. Air conditioner, scooter engine, thermometer  

2. Boiler, gas turbine, compressor

3. Pump, thermo flask , refrigerator

4. Boiler, thermometer , thermo flask

21. A loci of series of state changes during heat addition to a gas is…..

1. Process

2. Path

3. State change

4. None of the above

22. Which of the following is not a primary dimension?

1. Time

2. Length

3. Mass

4. Pressure

23. Macroscopic thermodynamics is also called……..

1. Statistical thermodynamics

2. Classical thermodynamics

3. Microscopic study

4. None of the above

24. Pressure of fluid-atmospheric pressure=……..

1. Absolute pressure

2. Barometric pressure

3. Gauge

4. None of the above

25. Which of the following is not a thermodynamic property?

1. Temperature

2. Pressure

3. Work

4. Internal energy

26. Which of the following set has all point functions?

1. Pressure ,temperature ,heat

2. Entropy , enthalpy, work

3. Temperature, enthalpy, internal energy

4. Heat, work, enthalpy

27. Property used in constant volume gas thermometer……

1. Length

2. Mass

3. Resistance

4. Volume

28. Thermodynamic boundary is part of……

1. System

2. Surrounding

3. Both (a) and (b) 

4. Neither (a) nor (b)

29. Work done upon the system and heat added to the system considered as…..

1. – and+

2. +,+

3. -,-

4. +,-

30. Thermodynamics equilibrium means………..

1. Mechanical equilibrium

2. Thermal equilibrium

3. Chemical equilibrium

1. 1 and 2

2. 1,2 and 3

3. 2and3

4. 1 and 3

31. Work done by expanding gas system and heat system given by it as considered as…..

1. -,+

2. +,+

3. -,-

4. +,-

32. For control volume approach which statement is true?

1. Boundaries are fixed 

2. Space under observation remains same

3. Boundaries are imaginary

1. 1 and 2

2. 1 and2

3. 1,2 and3

4. 2 and 3

33. Work is ………

1. Point function

2. Path function

3. Sometimes points 

4. Neither point nor path

34. Enthalpy remains constant for…….process

1. Throttling

2. Isothermal expansion

3. Free expansion

4. Isothermal compression

35. Which process cannot be irreversible?

1. Isothermal

2. Adiabatic

3. Throttling

4. None of these

36. For a perfect gas internal energy is a function of…….

1. Pressure

2. Temperature

3. Volume

4. All of these

37. Steady flow energy equation for boiler is ….

1. ∆q=h2-h1

2. ∆q=∆w

3. ∆q=0

4. none of these

38. Law of energy conservation is also known as …….law of thermodynamics

1. Zeroth

2. First

3. Second

4. Third

39. Efficiency of Carnot engine operation between temperature Tmax Tmin is minimum if ……….

1. Tmax=Tmin

2. Tmax<Tmin

3. Tmax>Tmin

4. None of these

40. A heat engine having 100% efficiency is not possible because it violates…….

1. Zeroth

2. First

3. Second

4. Third

41. What is not correct about a thermal reservoir?

1. Can absorb /reject any amount of heat

2. Has infinite heat capacity

3. Temperature changes if heat is added or rejected

4. None of these

42. What is not correct about heat engine?

1. Operating in a cycle

2. Operating between source and sinks

3. Reversible process

4. Converting heat into work

43. Efficiency of Carnot engine depends upon operating ……..range

1. Pressure

2. Volume 

3. Temperature

4. Calorific value

44. Internal energy of an ideal gas is a function of ……..

1. Temperature

2. Pressure

3. Volume

4. All of these

45. In reference to the first law of thermodynamics, correct statement is ………..

1. No difference between heat and work

2. No indication about direction of process

3. Law of energy conservation

4. All of the above

46. Carnot cycle consists of…………

1. Two reversible adiabatic and two reversible isothermal process

2. Two reversible adiabatic and two reversible isentropic process

3. Two reversible isothermal and two reversible isobaric process

4. Two reversible isobaric and two reversible isochoric process

47. What is not true about Carnot engine and Carnot cycle?

1. All the process are reversible

2. All the process require no time for completion

3. It is practically not feasible

4. It gives maximum theoretical efficiency

48. If Carnot heat engine works between 300k and 800k and rejects 900kj heat, then heat accepted is ……..

1. 2400kj

2. 500kj

3. 2700kj

4. 1200kj

49. Heat engine operating between T1 and 300k has efficiency 75% then T1 is…….

1. 75k

2. 1200k

3. 600k

4. None of these

50. Difference between COP of heat pump and COP of refrigerator is …………

1. 0

2. 1

3. >1

4. <1

51. Efficiency of Carnot engine can be increased by……

1. Reducing friction

2. Reducing operating temperature range

3. Increasing operating pressure

4. Increasing  operating temperature range

52. Heat transfer between a heat engine and source is…..

1. Directly proportional to absolute temperature of source

2. Inversely proportional to absolute temperature of source

3. Independent of source temperature

4. Dependent on engine working conditions

53. Efficiency of Carnot heat engine increases if……

1. Source temperature increase

2. Sink temperature decrease

3. Both a and b

4. Opposite a and b

53.    1) All adiabatic processes are isentropic

   2)  All isentropic processes are adiabatic of these statements, correct statements….

.A.1

B.2

C. Both 1 and 2

D. Neither 1 nor 2

55. COP of reversible heat pump is 1.25. If is reversed to run as reversible heat engine, then its efficiency is ……

1. 0.25

2. 1.25

3. 0.625

4. 0.8

55. COP of reversible refrigerator is 0.5. If it is reversed then efficiency of the heat engine is …….

1. 0.5

2. 0.75

3. 1.5

4. 0.67

55.  Efficiency of heat engine is 0.5. If it is reversed to work as refrigerator, its COP will be …….

1. 0.5

2. 1.5

3. 2

4. >1

56. Efficiency of heat engine is 0.75. If it is reversed to work as a heat pump then it COP will be…….

1. 0.75

2. 1.75

3. 1.33

4. 0.25

57. If x is a property of system then, incorrect statement is…..

1. It can be shown by a point on thermodynamics plane

2. It can be shown by a curve on a thermodynamic plane 

3. 12dx=x2-x1

4. 12dx=0

58.       1)   1 2dx=x2-x1    2) ∅dx=0. if x is a path function then,

1. 1) it is correct

2. 2) is correct

3. Both are correct

4. Both are incorrect

61.  What is incorrect about work?

1. Path function

2. Inexact differential

3. Energy to transit

4. Stored in system

62. Which of the following is not correct about the heat?

1. Path function

2. exact differential

3. Energy in transit

4. None of these

63. Which of the following is not a property?

1. Entropy

2. Enthalpy

3. Heat

4. Internal energy

64. Which of the following is not a property?

1. Pressure

2. Volume

3. Work

4. Entropy

65. Mixture of ice and water is…….system

1. Heterogeneous

2. Homogenous

3. Closed

4. Open

66. Which of the following is a path function?

1. Work

2. vdp

3. kinetic energy

4. Thermal conductivity

67. For a mole of different gases at same temperature and pressure, ……….constant

1. Enthalpy

2. Volume

3. Specific volume

4. Mass

68. Which is not a property of system?

1. pdv

2. vdp

3. Cyclic vdv

4. None of these

69. In a true sense, all engineering processes are……..

1. Quasi-static

2. Reversible

3. Irreversible

4. Equilibrium

70. More effective way of increasing efficiency of Carnot cycle

1. Increase lower temperature

2. Decrease lower temperature

3. Increase higher temperature

4. Decrease higher temperature

71.  False statement about Carnot cycle……….

1. It is considered as standard of perfection

2. It is provide concept of maximum performance  with given temperature range

3. The degree of perfection of other engines can be compared with Carnot engine

4. All thermal engines are based on Carnot engine

72. Carnot cycle maximum efficiency for……

1. Petrol engine

2. Diesel engine

3. Reversible engine

4. Irreversible 

73. Carnot cycle efficiency depends upon….

1. Medium used

2. Engine condition

3. Operating temperature range

4. Working condition

74. Heat interaction between a reservoir and a heat engine depends upon

1. Absolute temperature

2. Enthalpy reservoir

3. Absolute temperature of heat engine

4. Condition of engine

75. Carnot cycle efficiency is maximum when……

1. Source temperature is minimum

2. Sink temperature is maximum

3. Same source and sink temperature

4. Maximum difference between source and sink temperature

76. A heat engine works between 1200k and T2. Another works between T2 and 300k.  for both to have same efficiency , T2=……..

1. 750k

2. 600k

3. 900k

4. 1500k

77. For a control volume, which statement is true?

1. Matter remains same

2. Boundaries are fixed and real

1. Both 1 and 2 

2. Only 1

3. Only 2

4. Neither 1 nor 2

78. If heat exchange is reversible manner then change in…….. takes place accordingly

1. Enthalpy

2. Entropy

3. Temperature

4. Internal energy

79. If a system undergoes a series of process and returns to initial sate….

1. Its entropy will change due to irreversibility

2. Not work will be done

3. No heat transfer will take place

4. Sum of heat and work transfer will be zero

80. Which of the following is PMMI?

1. Heat engine with 100% thermal efficiency

2. Engine producing energy from sea water by using temperature difference 

3. A fully reversible heat engine

4. Engine having input of 60kj and producing 100kj continuously

81. What is violation of first law?

1. 100% efficient heat engine

2. Pushing the wall, but it is not moving

3. Cold tea boils on it is not working

4. Sum of all energies before accident is more than sum of the energies after accident

82. A real engine having same efficiency as Carnot engine is………

1. Possible

2. Impossible

3. Possible with number of sophistication

4. Feasible

83. In Carnot cycle, heat is transferred at constant

1. Pressure

2. Volume

3. Temperature

4. Entropy

84. In Carnot cycle, work is transferred at constant………

1. Pressure

2. Volume

3. Temperature

4. Entropy

85. Heat while operating between 27℃ and 227℃ and producing 20kW work by receiving 30kW heat is……..

1. Impossible

2. Theoretically possible

3. Practically possible

4. Possible with certain modification

86. When working substance rejects heat to sink in Carnot engine, temperature of sink ……..

1. Increases

2. Decreases

3. Remains same

4. Changes depending upon amount of heat

87. Second law of thermodynamics defines……

1. Entropy

2. Enthalpy

3. Heat

4. Internal energy

88. 1 barometric pressure =

1. 1 bar

2. 1 atm.pr.

3. 10 bar 

4. 10 atm. pr.

89. 1 atm. Pr= ….

1. 1 bar

2. 1.033 bar

3. 105 bar

4. 1.033 105 bar

90. An ideal gas at 27℃ is heated at constant pressure till its volume becomes four times. Its final temperature is……..

1. 108℃

2. 927℃

3. 54℃

4. 627℃

91. The cyclic integral of  ( Q-W) for an closed system

1. Positive

2. Negative

3. Zero

4. Unpredictable

92. Internal energy and enthalpy of ideal gas are function of…… 

1. Temperature

2. Predictable

3. Both temperature and pressure

4. None of these

93. Steady flow work for isothermal process 1-2……..

1. PV In P1P2

2. 0

3. mCp∆T

4. Cv(r-1)∆T

94. For isobaric process 1-2, steady flow work……

1. PV In P1P2

2. 0

3. mCp∆T

4. 1

95. For isochoric process 1-2, steady flow work is ………

1. PV In P1P2

2. 0

3. V(P1-P2)

4. P(V2-V1)

96. The amount of work that must be done to push a unit mass into or ou of the system boundary is called was-…..

1. Displacement work

2. Stirring work

3. Flow energy

4. Push work

97. For an unstrained  expansion-

1. dw=0

2. Pdv=0

3. dw>0

4. dw<0

98. for a free expansion-

1. dw>0,Pdv≠0

2. dw=0,Pdv≠0

3. dw0, pdv=0

4. dw=0

99. for w1-2=2 pdv be to valid , which is not a necessary condition-

1. quasi-static process

2. frictionless process

3. closed system

4. fixed boundaries

100. which of the following statement is not true about the first law of thermodynamics

1. It is law of conservation of energy

2. It was proved mathematically by J.P Joule

3. Heat pumps obey it

4. Irreversible heat engine obey it

101. The first law of thermodynamics is obeyed by

1. Only reversible heat engine

2. All reversible irreversible heat engine

3. Only reversible heat engine pumps and refrigerator

4. All the heat and irreversible heat engines , pumps and refrigerator

102. The value of mechanical equivalent of heat in SI units is 

1. 1 Nm 

2. 1 J

3. 1

4. 4.18

103. The necessary condition for thermal equilibrium is 

1. No temperature difference 

2. No imbalanced/force

3. No chemical reaction

4. All of these 

104. The quantity (δθ-δw)

1. Point function

2. Path function

3. Neither point nor path function

4. Dependant on the process taking place

105. The quantity (δθ-δw)

1. Is a point function

2. Is a path function

3. Is neither point function nor path function

4. Depends upon the process

106. Whenever there is function in a nozzle

1. The first law of thermodynamics is violated

2. The first law of thermodynamics is obeyed

3. Some energy is destroyed

4. Some energy is generator

107. If Q=0, W =0 Z1=Z2 and V2>>V1 the device considered is

1. Pump

2. Turbine

3. Nozzle

4. Diffuser

108. If Q=0, W =0 Z1=Z2 and V2<<V1, the device considered is 

1. Pump 

2. Turbine

3. Nozzle

4.  Diffuser

109. If  Q=0, z1=Z2, V1=V2, the device considered is

1. Throttle valve

2. Nozzle

3. Diffuser

4. Turbine

110. The S.F.E.E for a pump is

1. h1=h2

2. W=h1-h2

3. W=h2-h1

4. V2=2h2-h1

111. If Q=0,  W=0,  V1=V2, Z1=Z2, the device considered is

1. Nozzle

2. Pump

3. Diffuser

4. Throttle valve

112. The S.F.E.E for a diffuser is

1. W=h2-h1

2. V1=2(h2-h1)

3. W=h2-h1

4. h1=h2

113. the S.F.E.E for a porous plug is 

1. W=h2-h1

2. W=h2+h1

3. V2=2(h1-h2)

4. h1=h2

114. work done in a steady flow process is given by

1. jδw

2. δw+∆PE

3. δw+∆PE+∆KE

4. -pdv

115. The first law of thermodynamics defines which  property

1. Heat

2. Work

3. Enthalpy

4. Internal energy

116. The enthalpy and velocity of the steam entering the nozzle are 2750 KJ/kg and 50m/s and enthalpy exit is 2600 KJ/kg. What will be its velocity at exit ?

1. 500m./s

2. 550m/s

3. 0.55m/s

4. 01.50m/s

117. The inlet of nozzle is 0.1m2 and stem velocity and sp volume at inlet is 50 m/s and 0.18m2/kg respectively. What is its Mass flow rate?

1. 0.036kg/s

2. 9kg/s

3. 27.7kg/s

4. 0.9kg/s

118. If a machine required 1000 kj energy and its internal energy drops by 6000 kj. What will be its net heat transfer ?

1. -7000  kj

2. +7000 kj

3. -5000 kj

4. +5000 kj

119. If a system consumes 1 kwh energy and its internal drops by 2400 kj. What will be its net heat transfer ?

1. 1200 kj

2. -1200 kj

3. 6000 kj

4. -6000 kj

120. A Carnot engines having efficiency of 30 %  rejects heat to a reservoir at 27 ˚C. What is the temperature of source ?

1. 38.57˚C

2. 155.5˚C

3. 428.5˚ C

4. 210˚ C

121. The shaded area shows in the fig. 1.5

1. ʃ pdv

2. ʃ vdp

3. -ʃ pdv

4. -ʃ vdp

122. The shaded area in the fig shows in fig.1.6   

1. ʃ pdv 

2. ʃ vdp 

3. -ʃ pdv

4. -ʃ vdp

123. Heat engine with thermal efficiency of 100 percent is.

1. Possible according to fist law but impossible according to second law of thermodynamics

2. Possible according to second law but impossible according to second law of thermodynamics 

3. Possible according to first and second law of thermodynamics

4. Impossible according to first and second law of thermodynamic.

124. Thermal efficiency of a Carnot  heat engine depends upon-   

1.   Type of working medium. 

2. Types of processes carried out.

3. Different in temperatures of reservoirs.

4. All of above.

125. Which of the following are the ways to increase thermal efficiency of Carnot heat engine?

1. Making the process isentropic

2. Making process isothermal

3. Increasing the source temperature

4. All of these

126. In above process, if volume changes from 2m3 to 5m3. What is the work done?

1. 600KJ

2. 450KJ

3. 300KJ 

4. 150kj

127. What is the net work output?

1. 500KW

2. 200KW

3. 566KW

4. 133.33KW

128. What is the amount of heat supplied?

1. 200KW

2. 400KW

3. 300KW

4. Nil.

129. What is the thermal efficiency of the cycle?

1. 100%

2. 66.67%

3. 33.33%

4. Can’t be determined

130. What is the net change in internal energy?

1. Nil.

2. 200KW

3. 400KW

4. Data not sufficient

131. Which type of process is process AB?

1. Isobaric

2. Isochoric

3. Adiabatic

4. Isothermal

132. Process BC is………..process

1. Isobaric

2. Isochoric

3. Adiabatic

4. Isothermal

133. Which of the above processes are isothermal?

1. CD

2. DA

3. Both CD and DA

4. None

134. The change in internal energy for process CD is

1.  -566.67KW

2. -433.33KW

3. 556.67KW

4. 500KW

135. A heat engine operating between 127℃ and 27℃ and producing 300W of work when 1KW of heat is supplied to it is ……..machine

1. Ideal

2. Real

3. Impossible

4. Possible under specific condition

136. An open system is one in which……

1. Heat, work and/or mass cross boundary

2. Neither heat nor work nor mass crosses the boundary

3. Heat and work cross the boundary of system but mass does not

4. Mass crosses boundary but heat and work do not