MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 43 Mcqs, each offering curated multiple-choice questions to sharpen your Thermodynamics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Heat rate indicates? |
| A. | heat added per unit volume |
| B. | heat added per unit of work produced |
| C. | heat added per unit of mass stored |
| D. | heat added per unit area |
| Answer» C. heat added per unit of mass stored | |
| 2. |
Heat rejection in a condenser is to? |
| A. | cooled water |
| B. | coolant |
| C. | cooling water |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 3. |
What approximate percentage of energy in the fuel is converted to electricity? |
| A. | 55% |
| B. | 45% |
| C. | 35% |
| D. | 25% |
| Answer» D. 25% | |
| 4. |
Which of these shows the formula for the efficiencies of the auxiliaries n1? |
| A. | n1 = (net power transmitted by the generator x gross power produced by the plant) |
| B. | n1 = (net power transmitted by the generator / gross power input to the plant) |
| C. | n1 = (net power transmitted by the generator / gross power produced by the plant) |
| D. | n1 = (net power transmitted by the generator / gross power transferred by the plant) |
| Answer» D. n1 = (net power transmitted by the generator / gross power transferred by the plant) | |
| 5. |
If Q1 represents the rate of heat addition to the cycle and Wnet represents net cycle work output, the expression for net cycle heat rate is? |
| A. | Q1 + Wnet |
| B. | Q1 / Wnet |
| C. | Q1 / (1/Wnet) |
| D. | Q1 x Wnet |
| Answer» C. Q1 / (1/Wnet) | |
| 6. |
The mechanical efficiency of a turbine is given by? (ntm denotes the mechanical efficiency) |
| A. | ntm = (brake output of the turbine x internal output of the turbine) |
| B. | ntm = (internal output of the turbine / break output of the turbine) |
| C. | ntm = (brake output of the turbine / internal output of the turbine) |
| D. | ntm = (brake output of the turbine – internal output of the turbin |
| E. | ntm = (internal output of the turbine / break output of the turbine)c) ntm = (brake output of the turbine / internal output of the turbine)d) ntm = (brake output of the turbine – internal output of the turbine) |
| Answer» D. ntm = (brake output of the turbine – internal output of the turbin | |
| 7. |
Which of the following shows the correct relation? (nboiler denotes efficiency of a boiler) |
| A. | nboiler = (rate of energy absorption by water to form steam / rate of energy released by the combustion of fuel) |
| B. | nboiler = (rate of energy absorption by water to form steam + rate of energy released by the combustion of fuel) |
| C. | nboiler = (rate of energy absorption by water to form steam – rate of energy released by the combustion of fuel) |
| D. | nboiler = (rate of energy absorption by water to form steam x rate of energy released by the combustion of fuel) |
| Answer» B. nboiler = (rate of energy absorption by water to form steam + rate of energy released by the combustion of fuel) | |
| 8. |
The overall efficiency noverall of a steam power plant is given by? |
| A. | noverall = (power available at the generator terminals / (Fuel burning rate x Calorific Value of the fuel)) |
| B. | noverall = (power available at the generator terminals + (Fuel burning rate x Calorific Value of the fuel)) |
| C. | noverall = (power available at the generator terminals – (Fuel burning rate x Calorific Value of the fuel)) |
| D. | none of the mentioned |
| Answer» B. noverall = (power available at the generator terminals + (Fuel burning rate x Calorific Value of the fuel)) | |
| 9. |
The steam power plant is a bulk energy converter where fuel energy is converted to? |
| A. | heat energy |
| B. | electrical energy |
| C. | chemical energy |
| D. | none of the mentioned |
| Answer» C. chemical energy | |
| 10. |
Compressing steam in vapour form requires less work than compressing it in liquid form for same pressure rise. |
| A. | true |
| B. | false |
| Answer» C. | |
| 11. |
The efficiency of boiler is given by |
| A. | energy supplied / energy utilized |
| B. | energy utilized / energy supplied |
| C. | heat supplied / energy utilized |
| D. | none of the mentioned |
| Answer» C. heat supplied / energy utilized | |
| 12. |
The brake efficiency is given by |
| A. | brake output / internal output |
| B. | internal output / brake output |
| C. | brake output / heat supplied |
| D. | brake output / ideal output |
| Answer» E. | |
| 13. |
COMPRESSING_STEAM_IN_VAPOUR_FORM_REQUIRES_LESS_WORK_THAN_COMPRESSING_IT_IN_LIQUID_FORM_FOR_SAME_PRESSURE_RISE.?$ |
| A. | true |
| B. | false |
| Answer» C. | |
| 14. |
EFFICIENCY_OF_A_POWER_PLANT_IS_MORE_IN_SUMMERS_OR_WINTERS??$ |
| A. | summers |
| B. | winters |
| C. | same in both |
| D. | depends on variation |
| Answer» C. same in both | |
| 15. |
WHICH_OF_THESE_SHOWS_THE_FORMULA_FOR_THE_EFFICIENCIES_OF_THE_AUXILIARIES_N1??$ |
| A. | n<sub>1</sub> = (net power transmitted by the generator x gross power produced by the plant) |
| B. | n<sub>1</sub> = (net power transmitted by the generator / gross power input to the plant) |
| C. | n<sub>1</sub> = (net power transmitted by the generator / gross power produced by the plant) |
| D. | n<sub>1</sub> = (net power transmitted by the generator / gross power transferred by the plant) |
| Answer» D. n<sub>1</sub> = (net power transmitted by the generator / gross power transferred by the plant) | |
| 16. |
Heat rejection in a condenser is to?$ |
| A. | cooled water |
| B. | coolant |
| C. | cooling water |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 17. |
What_is_the_mechanical_efficiency_of_turbine?$ |
| A. | brake output / internal output |
| B. | internal output / brake output |
| C. | blade energy / energy supplied |
| D. | none of the mentioned |
| Answer» C. blade energy / energy supplied | |
| 18. |
What_approximate_percentage_of_energy_in_the_fuel_is_converted_to_electricity?$ |
| A. | 55% |
| B. | 45% |
| C. | 35% |
| D. | 25% |
| Answer» D. 25% | |
| 19. |
The relation between heat rate & efficiency is? |
| A. | both are directly proportional |
| B. | both are inversely proportional |
| C. | they are independent of each other |
| D. | heat rate is also called efficiency |
| Answer» C. they are independent of each other | |
| 20. |
Gross cycle heat rate is equal to? |
| A. | (rate of heat addition / turbine output) |
| B. | (rate of heat rejection / turbine input) |
| C. | (heat rejected / turbine output) |
| D. | none of the mentioned |
| Answer» B. (rate of heat rejection / turbine input) | |
| 21. |
Which of the following parameters affects the fuel economy? |
| A. | heat constant |
| B. | specific heat |
| C. | heat rate |
| D. | heat consumption |
| Answer» D. heat consumption | |
| 22. |
Heat_rate_indicates? |
| A. | heat added per unit volume |
| B. | heat added per unit of work produced |
| C. | heat added per unit of mass stored |
| D. | heat added per unit area |
| Answer» C. heat added per unit of mass stored | |
| 23. |
The efficiency of boiler is given b? |
| A. | energy supplied / energy utilized |
| B. | energy utilized / energy supplied |
| C. | heat supplied / energy utilized |
| D. | none of the mentioned |
| Answer» C. heat supplied / energy utilized | |
| 24. |
Name the major isotope present in steam generated in a Boiling Water Reactor? |
| A. | N-16 |
| B. | D-32 |
| C. | N-32 |
| D. | D-16 |
| Answer» B. D-32 | |
| 25. |
Which of these is not an auxiliary equipment in a power plant? |
| A. | Fans |
| B. | Crushers |
| C. | Galvanisers |
| D. | Conveyors |
| Answer» D. Conveyors | |
| 26. |
Which of the following efficiency is true? |
| A. | internal efficiency takes internal losses into consideration |
| B. | mechanical efficiency only considers the external losses |
| C. | brake efficiency considers both internal and external losses |
| D. | all of the mentioned |
| Answer» E. | |
| 27. |
What includes fixed cost? |
| A. | cost of land, Cost of building, Cost of equipment, Cost of installation |
| B. | interest |
| C. | management cost |
| D. | all of the mentioned |
| Answer» E. | |
| 28. |
The generator efficiency n of the electric alternator is? |
| A. | n = (electrical output at generator terminals / Brake output of the turbine) |
| B. | n = (electrical output at generator terminals x Brake output of the turbine) |
| C. | n = (electrical output at generator terminals / (1/ Brake output of the turbine)) |
| D. | none of the mentioned |
| Answer» B. n = (electrical output at generator terminals x Brake output of the turbine) | |
| 29. |
Under certain conditions, the specific enthalpies of dry steam, saturated water and wet steam are 2783 kJ/kg, 1219 kJ/kg and 2750 kJ/kg respectively. Determine the dryness fraction of wet steam. |
| A. | 0.01 |
| B. | 0.02 |
| C. | 0.021 |
| D. | 0.03 |
| Answer» D. 0.03 | |
| 30. |
If Q1 represents the rate of heat addition to the cycle and W represents net cycle work output, the expression for net cycle heat rate is ? |
| A. | Q<sub>1</sub> + W |
| B. | Q<sub>1</sub> / W |
| C. | Q<sub>1</sub> / (1/ W) |
| D. | Q<sub>1</sub> x W |
| Answer» C. Q<sub>1</sub> / (1/ W) | |
| 31. |
The mechanical efficiency is given by |
| A. | brake output / ideal output |
| B. | brake output / internal output |
| C. | brake output / heat supplied |
| D. | internal output / brake output |
| Answer» C. brake output / heat supplied | |
| 32. |
The steam from steam generator of a nuclear power plant is best described as |
| A. | superheated steam |
| B. | supercritical steam |
| C. | saturated dry steam |
| D. | saturated wet steam |
| Answer» E. | |
| 33. |
The mechanical efficiency of a turbine is given by? (ntm denotes the mechanical efficiency) |
| A. | n<sub>tm</sub> = (brake output of the turbine x internal output of the turbine) |
| B. | n<sub>tm</sub> = (internal output of the turbine / break output of the turbine) |
| C. | n<sub>tm</sub> = (brake output of the turbine / internal output of the turbine) |
| D. | n<sub>tm</sub> = (brake output of the turbine – internal output of the turbine) |
| Answer» D. n<sub>tm</sub> = (brake output of the turbine ‚Äö√Ñ√∂‚àö√ë‚àö¬® internal output of the turbine) | |
| 34. |
Overall efficiency is the ratio of power available at generator terminals to rate of energy released by combustion of fuel. |
| A. | true |
| B. | false |
| C. | can’t say |
| D. | not true for all conditions |
| Answer» B. false | |
| 35. |
Which of the following shows the correct relation? (nboiler denotes efficiency of a boiler) |
| A. | n<sub>boiler</sub> = (rate of energy absorption by water to form steam / rate of energy released by the combustion of fuel) |
| B. | n<sub>boiler</sub> = (rate of energy absorption by water to form steam + rate of energy released by the combustion of fuel) |
| C. | n<sub>boiler</sub> = (rate of energy absorption by water to form steam – rate of energy released by the combustion of fuel) |
| D. | n<sub>boiler</sub> = (rate of energy absorption by water to form steam x rate of energy released by the combustion of fuel) |
| Answer» B. n<sub>boiler</sub> = (rate of energy absorption by water to form steam + rate of energy released by the combustion of fuel) | |
| 36. |
The generator efficiency is given by brake output / output at generator terminals. |
| A. | true |
| B. | false |
| Answer» C. | |
| 37. |
The lower is the value of heat rate, __________ is the efficiency. |
| A. | lower |
| B. | higher |
| C. | same |
| D. | depends on further parameters |
| Answer» C. same | |
| 38. |
The overall efficiency noverall of a steam power plant is given by? |
| A. | n<sub>overall</sub> = (power available at the generator terminals / (Fuel burning rate x Calorific Value of the fuel)) |
| B. | n<sub>overall</sub> = (power available at the generator terminals + (Fuel burning rate x Calorific Value of the fuel)) |
| C. | n<sub>overall</sub> = (power available at the generator terminals – (Fuel burning rate x Calorific Value of the fuel)) |
| D. | none of the mentioned |
| Answer» B. n<sub>overall</sub> = (power available at the generator terminals + (Fuel burning rate x Calorific Value of the fuel)) | |
| 39. |
The internal efficiency is given by |
| A. | internal output / ideal output |
| B. | ideal output / internal output |
| C. | internal output / heat supplied |
| D. | none of the mentioned |
| Answer» B. ideal output / internal output | |
| 40. |
Maximum energy of a power plant is lost in? |
| A. | condensor |
| B. | pump |
| C. | boiler |
| D. | environment |
| Answer» B. pump | |
| 41. |
Rate of energy released by the combustion of the fuel is given by? |
| A. | Fuel burning rate x Calorific Value of the fuel |
| B. | Fuel burning rate / Calorific Value of the fuel |
| C. | Fuel burning rate + Calorific Value of the fuel |
| D. | Fuel burning rate – Calorific Value of the fuel |
| Answer» B. Fuel burning rate / Calorific Value of the fuel | |
| 42. |
The work done in irreversible adiabatic expansion by the turbine is called |
| A. | external work |
| B. | internal work |
| C. | zero work |
| D. | useful work |
| Answer» C. zero work | |
| 43. |
The maximum work output that can be obtained per unit mass of steam is |
| A. | reversible and isobaric enthalpy drop in turbine |
| B. | reversible and isochoric enthalpy drop in turbine |
| C. | reversible and adiabatic enthalpy drop in turbine |
| D. | all of the mentioned |
| Answer» D. all of the mentioned | |