MCQOPTIONS
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MCQOPTIONS
This section includes 17 Mcqs, each offering curated multiple-choice questions to sharpen your Thermodynamics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Second law efficiency is defined as the ratio of actual thermal efficiency to the maximum possible thermal efficiency. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 2. |
Two engines having same thermal efficiency but supplied with heat from source at different temperatures, |
| A. | will convert same fraction of heat they receive into work |
| B. | from second law, one will perform better than other |
| C. | this can be considered as a deficiency of the first law |
| D. | all of the mentioned |
| Answer» E. | |
| 3. |
For a total reversible process, |
| A. | W reversible = useful work |
| B. | irreversibility = 0 |
| C. | both of the mentioned |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 4. |
The difference between the reversible work and the useful work for a process is called irreversibility. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 5. |
If the final state of the system is the dead state, the ____ and the ____ become identical. |
| A. | reversible work, exergy |
| B. | irreversible work, exergy |
| C. | reversible work, irreversible work |
| D. | none of the mentioned |
| Answer» B. irreversible work, exergy | |
| 6. |
Useful work is given by |
| A. | difference between the actual work and the surrounding work |
| B. | W – W for surroundings |
| C. | W – p(V2-V1) |
| D. | all of the mentioned |
| Answer» E. | |
| 7. |
THE_DIFFERENCE_BETWEEN_THE_REVERSIBLE_WORK_AND_THE_USEFUL_WORK_FOR_A_PROCESS_IS_CALLED_IRREVERSIBILITY.?$ |
| A. | true |
| B. | false |
| Answer» B. false | |
| 8. |
Two engines having same thermal efficiency but supplied with heat from source at different temperatures,$ |
| A. | will convert same fraction of heat they receive into work |
| B. | from second law, one will perform better than other |
| C. | this can be considered as a deficiency of the first law |
| D. | all of the mentioned |
| Answer» E. | |
| 9. |
For_a_total_reversible_process,$ |
| A. | W reversible = useful work |
| B. | irreversibility = 0 |
| C. | both of the mentioned |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 10. |
In the context of first law efficiency and second law efficiency, which of the following statement is true? |
| A. | first law efficiency = energy output / energy input and their difference is the energy loss |
| B. | second law efficiency = exergy output / exergy input and their difference is irreversibility |
| C. | by reducing energy loss, first law efficiency can be reduced and by reducing irreversibilities, second law efficiency can be reduced |
| D. | all of the mentioned |
| Answer» E. | |
| 11. |
Second_law_efficiency_is_defined_as_the_ratio_of_actual_thermal_efficiency_to_the_maximum_possible_thermal_efficiency. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 12. |
If the final state of the system is the dead state, the ____ and the ____ become identical? |
| A. | reversible work, exergy |
| B. | irreversible work, exergy |
| C. | reversible work, irreversible work |
| D. | none of the mentioned |
| Answer» B. irreversible work, exergy | |
| 13. |
The maximum amount of useful work that can be obtained from a system as it undergoes a process between two specified states is called |
| A. | adiabatic work |
| B. | reversible work |
| C. | irreversible work |
| D. | none of the mentioned |
| Answer» C. irreversible work | |
| 14. |
The surrounding work is zero for |
| A. | cyclic devices |
| B. | steady flow devices |
| C. | system with fixed boundaries |
| D. | all of the mentioned |
| Answer» E. | |
| 15. |
A dead state |
| A. | is in equilibrium with its surroundings |
| B. | has zero exergy |
| C. | both of the mentioned |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 16. |
Exergy is a composite property. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 17. |
____ is conserved but ____ is not conserved. |
| A. | exergy, energy |
| B. | energy, exergy |
| C. | both exergy and energy are conserved |
| D. | neither exergy nor energy is conserved |
| Answer» C. both exergy and energy are conserved | |