MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
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 piston-cylinder has the piston loaded with outside atmospheric pressure and piston mass to a pressure of 150 kPa. It contains water at −2°C, which is heated until the water becomes saturated vapour. Find the specific work for the process. |
| A. | 163.7 kJ/kg |
| B. | 173.7 kJ/kg |
| C. | 183.7 kJ/kg |
| D. | 193.7 kJ/kg |
| Answer» C. 183.7 kJ/kg | |
| 2. |
A reactor filled with water having volume 1 m3 is at 360°C, 20 MPa and placed inside a containment room which is well insulated and initially evacuated. Due to a failure, the reactor ruptures and water fills the room. Find the minimum room volume so that the final pressure does not exceed 200 kPa. |
| A. | 257.7 m3 |
| B. | 267.7 m3 |
| C. | 277.7 m3 |
| D. | 287.7 m3 |
| Answer» E. | |
| 3. |
An insulated cylinder fitted with a piston contains R-12 at 25°C with a quality of 90% and V=45 L. The piston moves and the R-12 expands until it exists as saturated vapour. During this, R-12 does 7kJ of work against the piston. Determine the final temperature, assuming that the process is adiabatic. |
| A. | -5°C |
| B. | -15°C |
| C. | -25°C |
| D. | -35°C |
| Answer» C. -25°C | |
| 4. |
A 25 kg mass moving with 25 m/s is brought to a complete stop with a constant deceleration over a period of 5 seconds by a brake system. The brake energy is absorbed by 0.5kg water initially at 100 kPa, 20°C. Assume that the mass is at constant P and T. Find the energy the brake removes from the mass assuming P = C. |
| A. | 7.6125 kJ |
| B. | 7.7125 kJ |
| C. | 7.8125 kJ |
| D. | 7.9125 kJ |
| Answer» D. 7.9125 kJ | |
| 5. |
2kg water at 120°C with a quality of 25% has its temperature raised 20°C in a constant volume process. What is the heat transfer in the process? |
| A. | 877.8 kJ |
| B. | 887.8 kJ |
| C. | 897.8 kJ |
| D. | 907.8 kJ |
| Answer» B. 887.8 kJ | |
| 6. |
A constant pressure piston-cylinder contains 0.2 kg water as saturated vapour at 400 kPa. It is now cooled so that the water occupies half the original volume. Find the heat transfer in the process. |
| A. | –203.9 kJ |
| B. | –233.9 kJ |
| C. | –223.9 kJ |
| D. | –213.9 kJ |
| Answer» E. | |
| 7. |
A cylinder with constant volume of 0.1 L contains water at critical point. It then cools down to room temperature of 20°C. Calculate the heat transfer from the water. |
| A. | -61.7 kJ |
| B. | -71.7 kJ |
| C. | -81.7 kJ |
| D. | -91.7 kJ |
| Answer» B. -71.7 kJ | |
| 8. |
Water in a 150L closed, rigid tank is at 100°C, 90% quality. The tank is cooled to −10°C. Calculate the heat transfer during this process. |
| A. | -163.3 kJ |
| B. | -263.3 kJ |
| C. | -363.3 kJ |
| D. | -463.3 kJ |
| Answer» C. -363.3 kJ | |
| 9. |
Ammonia at 0°C, quality 60% is contained in a 200L tank. The tank and ammonia is now heated to a final pressure of 1 MPa. Determine the heat transfer for the process. |
| A. | 520.75 kJ |
| B. | 620.75 kJ |
| C. | 720.75 kJ |
| D. | 820.75 kJ |
| Answer» D. 820.75 kJ | |
| 10. |
A cylinder fitted with a piston contains 2kg of superheated R-134a vapour at 100°C, 350 kPa. The cylinder is then cooled so that R-134a remains at constant pressure till it reaches a quality of 75%. Calculate the heat transfer in this process. |
| A. | -174.6 kJ |
| B. | -274.6 kJ |
| C. | -374.6 kJ |
| D. | -474.6 kJ |
| Answer» C. -374.6 kJ | |
| 11. |
A rigid container has 0.75kg water at 1200 kPa, 300°C. Now, the water is cooled to a final pressure of 300 kPa. Find the heat transfer in the process. |
| A. | -2348 kJ |
| B. | -1348 kJ |
| C. | -2148 kJ |
| D. | -1148 kJ |
| Answer» E. | |
| 12. |
A 100L rigid tank contains nitrogen at 3 MPa, 900 K. The tank is then cooled to 100 K. What is the heat transfer for this process? |
| A. | −490.7 kJ |
| B. | −590.7 kJ |
| C. | −690.7 kJ |
| D. | −790.7 kJ |
| Answer» D. −790.7 kJ | |