 
			 
			MCQOPTIONS
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				This section includes 13 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 rock bed(at 70 C) consists of 6000 kg granite. A house with mass of 12000 kg wood and 1000 kg iron is at 15 C. They are brought to a uniform final temperature. Find the irreversibility of the process, assuming an ambient temperature of 15 C. | 
| A. | 17191 kJ | 
| B. | 18191 kJ | 
| C. | 19191 kJ | 
| D. | 20191 kJ | 
| Answer» C. 19191 kJ | |
| 2. | A 2-kg piece of iron is heated from temperature 25 C to 400 C by a heat source which is at 600 C. What is the irreversibility in the process? | 
| A. | 96.4 kJ | 
| B. | 86.4 kJ | 
| C. | 76.4 kJ | 
| D. | 66.4 kJ | 
| Answer» B. 86.4 kJ | |
| 3. | A heat exchanger increases the availability of 3 kg/s water by 1650 kJ/kg by using 10 kg/s air which comes in at 1400 K and leaves with 600 kJ/kg less availability. What is the irreversibility? | 
| A. | 1020 kW | 
| B. | 1030 kW | 
| C. | 1040 kW | 
| D. | 1050 kW | 
| Answer» E. | |
| 4. | If two streams with equal temperature are mixing, then the entropy generation number becomes | 
| A. | 0 | 
| B. | 1 | 
| C. | -1 | 
| D. | infinity | 
| Answer» B. 1 | |
| 5. | Entropy generation number can be given by | 
| A. | (rate of entropy generation)*(mass flow rate/specific heat) | 
| B. | (rate of entropy generation)/(mass flow rate/specific heat) | 
| C. | (rate of entropy generation)*(mass flow rate*specific heat) | 
| D. | (rate of entropy generation)/(mass flow rate*specific heat) | 
| Answer» E. | |
| 6. | The decrease in availability or lost work is proportional to | 
| A. | pressure drop | 
| B. | mass flow rate | 
| C. | both of the mentioned | 
| D. | none of the mentioned | 
| Answer» D. none of the mentioned | |
| 7. | Heat transfer through a finite temperature difference is equivalent to the destruction of its exergy. | 
| A. | true | 
| B. | false | 
| Answer» B. false | |
| 8. | A thermodynamically efficient process would involve ____ exergy loss with ____ rate of entropy generation. | 
| A. | minimum, minimum | 
| B. | maximum, maximum | 
| C. | minimum, maximum | 
| D. | maximum, minimum | 
| Answer» B. maximum, maximum | |
| 9. | The quantity [To*( Ssystem + Ssurroundings)] represents an increase in | 
| A. | available energy | 
| B. | unavailable energy | 
| C. | exergy | 
| D. | all of the mentioned | 
| Answer» C. exergy | |
| 10. | For irreversibility, same expression applies to both flow and non-flow processes. | 
| A. | true | 
| B. | false | 
| Answer» B. false | |
| 11. | For a non-flow process between equilibrium states, when the system exchanges heat only with the environment | 
| A. | I=0 | 
| B. | I>0 | 
| C. | I<0 | 
| D. | I>=0 | 
| Answer» E. | |
| 12. | Irreversibility(I) is also called | 
| A. | degradation | 
| B. | dissipation | 
| C. | both of the mentioned | 
| D. | none of the mentioned | 
| Answer» D. none of the mentioned | |
| 13. | The actual work done by a system is always ____ than the reversible work, and the difference between the two is called ____ of the process. | 
| A. | more, irreversibility | 
| B. | less, irreversibility | 
| C. | more, reversibility | 
| D. | less, reversible | 
| Answer» C. more, reversibility | |