Explore topic-wise MCQs in Thermodynamics.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Thermodynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

Find the specific reversible work for a R-134a compressor with inlet state of 20 C, 100 kPa and an exit state of 600 kPa, 50 C. Use a 25 C ambient temperature.

A. 48.878 kJ/kg
B. -38.878 kJ/kg
C. 48.878 kJ/kg
D. -38.878 kJ/kg
Answer» C. 48.878 kJ/kg
2.

Air in a piston/cylinder arrangement is at 25 C, 110 kPa with a volume of 50 L. It goes through a reversible polytropic process to final state of 500 K, 700 kPa and exchanges heat with the ambient at 25 C. Find the total work from the ambient.

A. -9.28 kJ
B. -9.38 kJ
C. -9.48 kJ
D. -9.58 kJ
Answer» E.
3.

A wooden bucket(2 kg) with 10 kg hot liquid water, both at 85 C, is lowered down to 400 m into a mineshaft. What is the availability of water and bucket with respect to the surface with ambient temperature of 20 C?

A. 232.2 kJ
B. 242.2 kJ
C. 212.2 kJ
D. 252.2 kJ
Answer» B. 242.2 kJ
4.

R-12 at 30 C, 0.75 MPa enters a steady flow device and exits at 30 C, 100 kPa. Assuming the process to be isothermal and reversible, find the change in availability of the refrigerant.

A. -26.1 kJ/kg
B. -36.1 kJ/kg
C. -46.1 kJ/kg
D. -56.1 kJ/kg
Answer» C. -46.1 kJ/kg
5.

Nitrogen is flowing in a pipe with a of velocity 300 m/s at 500 kPa, 300 C. What is its availability relative to an ambient at 100 kPa, 20 C?

A. 272 kJ/kg
B. 252 kJ/kg
C. 292 kJ/kg
D. 232 kJ/kg
Answer» B. 252 kJ/kg
6.

Cold water is running in a river at 2 C and the air temperature is 20 C. What is the availability of water relative to the ambient temperature?

A. 2.157 kJ/kg
B. 2.857 kJ/kg
C. 3.457 kJ/kg
D. 2.457 kJ/kg
Answer» E.
7.

A steady stream of R-22 at ambient temperature of 10 C, and at 750 kPa enters a solar collector. The stream exits at 80 C, 700 kPa. Calculate the change in availability.

A. 4.237 kJ/kg
B. 5.237 kJ/kg
C. 6.237 kJ/kg
D. 7.237 kJ/kg
Answer» D. 7.237 kJ/kg
8.

Find the specific reversible work for a compressor using R-134a with inlet state of 20 C, 100 kPa and an exit state of 50 C, 600 kPa. Use 25 C as ambient temperature.

A. -28.878 kJ/kg
B. -38.878 kJ/kg
C. -48.878 kJ/kg
D. -58.878 kJ/kg
Answer» C. -48.878 kJ/kg
9.

Find the specific reversible work for a steam turbine with inlet at 4 MPa, 500 C and an actual exit state of 100 kPa, x = 1.0 with a 25 C ambient temperature.

A. 550.0 kJ/kg
B. 650.0 kJ/kg
C. 750.0 kJ/kg
D. 850.0 kJ/kg
Answer» E.
10.

The compressor in a refrigerator takes R-134a in at 100 kPa, 20 C and then compresses it to 1 MPa, 40 C. With the room temperature at 20 C find the minimum compressor work.

A. -48.19 kJ/kg
B. -58.19 kJ/kg
C. -68.19 kJ/kg
D. -78.19 kJ/kg
Answer» B. -58.19 kJ/kg