MCQOPTIONS
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MCQOPTIONS
This section includes 13 Mcqs, each offering curated multiple-choice questions to sharpen your Aerodynamics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Why is a variable geometry diffuser used? |
| A. | Ease in manufacturing |
| B. | Higher efficiency |
| C. | More mass flow rate |
| D. | Inexpensive |
| Answer» C. More mass flow rate | |
| 2. |
What happens if the second throat area is larger than the starting value when the wind tunnel starts and the reservoir pressure value is opened? |
| A. | Normal shock is swallowed by diffuser |
| B. | Normal shock remains upstream of diffuser |
| C. | Throat area has no effect |
| D. | Normal shock is generated at the inlet |
| Answer» B. Normal shock remains upstream of diffuser | |
| 3. |
What is the entropy relation between the entry and exit of an actual diffuser? |
| A. | s<sub>1</sub> = s<sub>2</sub> |
| B. | s<sub>1</sub> > s<sub>2</sub> |
| C. | s<sub>1</sub> < s<sub>2</sub> |
| D. | s<sub>1</sub> s<sub>2</sub> = 1 |
| Answer» D. s<sub>1</sub> s<sub>2</sub> = 1 | |
| 4. |
What is the diffuser efficiency of a normal shock diffuser? |
| A. | 1 |
| B. | 0 |
| C. | Inifinty |
| D. | ( frac {1}{2} ) |
| Answer» B. 0 | |
| 5. |
What is the diffuser efficiency for supersonic flow? |
| A. | <sub>D</sub> = 1 |
| B. | <sub>D</sub> > 1 |
| C. | <sub>D</sub> < 1 |
| D. | <sub>D</sub> = 1/2 |
| Answer» C. <sub>D</sub> < 1 | |
| 6. |
Why is the diffuser throat area greater than the nozzle throat area? |
| A. | To reduce speed |
| B. | To maintain constant mass flow rate |
| C. | Rise in entropy within diffuser |
| D. | Rise in entropy within nozzle |
| Answer» D. Rise in entropy within nozzle | |
| 7. |
Which of these phenomena attenuates the advantages of greater pressure recovery in an oblique shock diffuser? |
| A. | Abrupt change of convergent divergent sections |
| B. | Shock wave interaction with walls |
| C. | Isentropic flow |
| D. | Presence of normal shock |
| Answer» C. Isentropic flow | |
| 8. |
Oblique shock diffuser has a better pressure recovery than a normal shock diffuser. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 9. |
Total pressure loss in a normal shock diffuser is less than the oblique shock diffuser. |
| A. | True |
| B. | False |
| Answer» C. | |
| 10. |
Why can t build an ideal supersonic diffuser with no total pressure losses? |
| A. | Presence of shock waves |
| B. | Varying cross sectional area |
| C. | Varying throat area |
| D. | Choked flow |
| Answer» B. Varying cross sectional area | |
| 11. |
Which of these properties remain constant in the ideal isentropic supersonic diffuser? |
| A. | Total pressure |
| B. | Velocity |
| C. | Mach number |
| D. | Mass flow |
| Answer» B. Velocity | |
| 12. |
How is flow deaccelerated In the diffuser? |
| A. | Isentropic compression |
| B. | Isentropic expansion |
| C. | Adiabatic compression |
| D. | Adiabatic expansion |
| Answer» B. Isentropic expansion | |
| 13. |
What is the role of the diffuser? |
| A. | Increase the flow velocity after test section |
| B. | Decrease the flow velocity after test section |
| C. | Increase the flow velocity inside test section |
| D. | Decrease the flow velocity inside the test section |
| Answer» C. Increase the flow velocity inside test section | |