Top Thermodynamics mcqs

 

1. At NTP, the volume of a g mol of all gases is(in liters)?

A) 22.1
B) 22.2
C) 22.3
D) 22.4

ANSWER= (D) 22.4
Explain:- This comes from the Avogadro’s law.

 

2. Which of the following statement is true?

A) number of kg moles of a gas = mass / molecular weight
B) molar volume = total volume of the gas / number of kg moles
C) both of the mentioned
D) none of the mentioned

ANSWER= (C) both of the mentioned
Explain:- Number of moles is in kg moles and molar volume is in (m^3)/kg mol.

 

3.A definite area or a space where some thermodynamic process takes place is known as?

A) Thermodynamics system
B) Thermodynamic cycle
C) Thermodynamic process
D) Thermodynamic law

ANSWER= (A) Thermodynamic system
Explain:- A thermodynamic system is a group of matter and radiation that is enclosed in space by walls with defined permeability that isolate it from its surroundings..

 

4. A closed system is one in which heat and work crosses the boundary of the system but the mass of the working substance does not crosses the boundary of the system?

A) yes
B) No

ANSWER= (A) Yes
Explain:- A closed system is that in which only the exchange of energy is allowed but the exchange of matter is not allowed.

 

5. In an extensive property of a thermodynamic system?

A) extensive heat is transferred
B) extensive work is done
C) extensive energy is utilized
D) none of these

ANSWER= (d) none of these
Explain:-

 

6. 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?

A) is equal to
B) is not equal to

ANSWER= (A) equal to

 

7. Which of the following is the extensive property of a thermodynamic system?

A) Pressure
B) Volume
C) Temperature
D) Density

ANSWER= (B) Volume

 

8. Which of the following is an intensive property of thermodynamic system?

A) Volume
B) Temperature
C) Mass
D) Energy

ANSWER= (B) temperature

 

9. The specific volume of a system is an ------- property ?

A) extensive
B) intensive
C) drafting and documentation
D) none of the mentioned

ANSWER= (B) extensive

 

10. The absolute zero is taken as ?

A) -273 °C
B) 273 °C
C) 237 °C
D) -237 °C

ANSWER= (A) -273 °C

 

11. Which of the following is correct ?

A) Absolute pressure = Gauge pressure + Atmospheric pressure
B) Gauge pressure = Absolute pressure + Atmospheric pressure
C) Atmospheric pressure = Absolute pressure + Gauge pressure
D) Absolute pressure = Gauge pressure - Atmospheric pressure

ANSWER= (A) Absolute pressure = Gauge pressure + Atmospheric pressure

 

12. The standard value of atmospheric pressure taken at sea level is?

A) 1.013 bar
B) 760 mm of Hg
C) 1013 × 102 N/m2
D) All of these

ANSWER= (D) All of these

 

13. The value of one bar (in S. I. units) is equal to?

A) 1 × 102 N/m2
B) 1 × 103 N/m2
C) 1 × 104 N/m2
D) 1 × 105 N/m2

ANSWER= (D) 1 × 105 N/m2
Explain:-

 

14. The reading of pressure gauge fitted on a vessel is 25 bar.The atmospheric pressure is 1.03 bar and the value of g is 9.81m/s2 . The absolute pressure in the vessel is ?

A) 23.97 bar
B) 25 bar
C) 26.03 bar
D) 34.81 bar

ANSWER= (C) 26.03 bar
Explain:-

 

15. The condition of temperature and pressure at 0°C (273) and 760 mm of Hg pressure are termed as -------- temperature and pressure ?

A) Normal
B) standard
C) zero
D) non of the above

ANSWER= (B) standard
Explain:-

 

16. The unit of energy in S.I unit is?

A) Joule (J)
B) Joule meter (Jm)
C) Watt (W)
D) Joule per meter (J/m)

ANSWER= (A) Joule
Explain:-

 

17. The unit of power in S.I unit is kilowatt?

A) True
B) False

ANSWER= (A) True
Explain:-

 

18. One kilowatt is equal to?

A) 1 N-m/s
B) 100 N-m
C) 1000 N-m/s
D)10 KN-m/s)

ANSWER= (C) 1000 N-m/s
Explain:-

 

19.One joule (J) is equal to ?

A) 1 N-m
B) 1 KN-m
C) 10 N-m/s
D) 10 KN-m/s

ANSWER= A) 1 N-m
Explain:-

 

20.The specific heat of water is?

A) 1.817
B) 2.512
C) 4.187
D) none of these

ANSWER= 4.187
Explain:-

 

21.The numerical value of the thermal capacity and the water equivalent of the substance are the same ?

A) agree
B) disagree
C) 4.187
D) none of these

ANSWER= A) agree
Explain:-

 

22.The heat and mechanical energies are mutually convertible. This statement was established by.?

A) Boyle
B) Charles
C) Joule
D) none of these

ANSWER= C) Joule
Explain:-

 

22.Which of the following statement is correct?p>

A) Systems never possess heat but work can be
B) Both heat and work are path functions
C) While work is a boundary phenomenon heat is not
D) Both heat and work are inexact differentials

ANSWER= B) Both heat and work are path functions
Explain:-