Explore topic-wise MCQs in Thermodynamics.

This section includes 12 Mcqs, each offering curated multiple-choice questions to sharpen your Thermodynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

A_CYLINDER/PISTON_CONTAINS_CARBON_DIOXIDE_AT_300¬¨ àûC,_1_MPA_WITH_A_VOLUME_OF_200L._THE_TOTAL_EXTERNAL_FORCE_ACTING_ON_THE_PISTON_IS_PROPORTIONAL_TO_V3._THIS_SYSTEM_IS_ALLOWED_TO_COOL_TO_ROOM_TEMPERATURE,_20¬¨ àûC._FIND_THE_WORK.?$#

A. -24.4 kJ
B. -34.4 kJ
C. -44.4 kJ
D. -54.4 kJ
Answer» B. -34.4 kJ
Discussion
2.

A mass of 2 kg ethane gas at 100°C, 500 kPa, undergoes a reversible polytropic expansion with n = 1.3, to a final temperature of 20°C. Find the work done.$#

A. 43.7 kJ/kg
B. 53.7 kJ/kg
C. 63.7 kJ/kg
D. 73.7 kJ/kg
Answer» E.
Discussion
3.

A_cylinder/piston_contains_100L_of_air_at_25°C,_110_kPa._The_air_is_compressed_in_a_reversible_polytropic_process_to_a_final_state_of_200°C,_800_kPa._Assume_the_heat_transfer_is_with_the_ambient_at_25°C._Find_the_work_done_by_the_air.$#

A. -11.28 kJ
B. -21.28 kJ
C. -31.28 kJ
D. -41.28 kJ
Answer» C. -31.28 kJ
Discussion
4.

A cylinder/piston contains saturated vapour R-22 at 10°C; the volume is 10 L. The R-22 is compressed to 60°C, 2 MPa in a reversible polytropic process. If all the heat transfer during the process is with the ambient at 10°C, calculate the work done.$

A. ‚àí6.26 kJ
B. ‚àí7.26 kJ
C. ‚àí8.26 kJ
D. ‚àí9.26 kJ
Answer» C. ‚Äö√Ñ√∂‚àö‚Ć‚àö‚â†8.26 kJ
Discussion
5.

A piston/cylinder contains air at 100 kPa, 300 K. A reversible polytropic process with n = 1.3 brings the air to 500 K. Any heat transfer if it comes in is from a 325°C reservoir and if it goes out it is to the ambient at 300 K. Find the specific work.$

A. -171.3 kJ/kg
B. -181.3 kJ/kg
C. -191.3 kJ/kg
D. -201.3 kJ/kg
Answer» D. -201.3 kJ/kg
Discussion
6.

Consider air in a cylinder volume of 0.2 L at 7 MPa, 1800K. It now expands in a reversible polytropic process with exponent, n = 1.5, through a volume ratio of 8:1. Calculate the work for the process?

A. 1.61 kJ
B. 1.71 kJ
C. 1.81 kJ
D. 1.91 kJ
Answer» D. 1.91 kJ
Discussion
7.

Helium in a piston/cylinder at 20°C, 100 kPa is brought to 400 K in a reversible polytropic process with exponent n = 1.25. Helium can be assumed to be an ideal gas with constant specific heat. Find the specific work.$

A. -587.7 kJ/kg
B. -687.7 kJ/kg
C. -787.7 kJ/kg
D. -887.7 kJ/kg
Answer» E.
Discussion
8.

A cylinder/piston contains 1kg methane gas at 100 kPa, 20°C. The gas is compressed reversibly to a pressure of 800 kPa. Calculate the work required if the process is isothermal.$

A. -216.0 kJ
B. -316.0 kJ
C. -416.0 kJ
D. -516.0 kJ
Answer» C. -416.0 kJ
Discussion
9.

A mass of 1kg of air contained in a cylinder at 1000 K, 1.5 MPa, expands in a reversible adiabatic process to 100 kPa. Calculate the work done during the process using Constant specific heat.

A. 286.5 kJ
B. 386.5 kJ
C. 486.5 kJ
D. 586.5 kJ
Answer» C. 486.5 kJ
Discussion
10.

Neon at 400 kPa, 20°C is brought to 100°C in a polytropic process with n = 1.4. Find the work done.$

A. -52.39 kJ/kg
B. -62.39 kJ/kg
C. -72.39 kJ/kg
D. -82.39 kJ/kg
Answer» E.
Discussion
11.

The piston/cylinder contains carbon dioxide at 300 kPa, with volume of 0.2 m3 and at 100°C. Mass is added at such that the gas compresses with PV^(1.2) = constant to a final temperature of 200°C. Determine the work done during the process.$

A. -80.4 kJ
B. -40.4 kJ
C. -60.4 kJ
D. -50.4 kJ
Answer» B. -40.4 kJ
Discussion
12.

A polytropic process(n = ‚àí 1) starts with P = 0, V = 0 and ends with P= 600 kPa, V = 0.01 m3. Find the boundary work done.

A. 1 kJ
B. 2 kJ
C. 3 kJ
D. 4 kJ
Answer» D. 4 kJ
Discussion