MCQOPTIONS
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MCQOPTIONS
This section includes 14 Mcqs, each offering curated multiple-choice questions to sharpen your Fluid Mechanics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
What can be the maximum diameter of the pipe for the water flow of velocity 1 m/s (ν = 10-6) to be laminar in nature? Assume Lower critical Reynolds number to be 2100. |
| A. | 2.1 mm |
| B. | 21 mm |
| C. | 21 cm |
| D. | 0.21 mm |
| Answer» B. 21 mm | |
| 2. |
Water flows through a circular tube with a velocity of 2 m/s. The diameter of the pipe is 14 cm. Take kinematic viscosity of water 10-6 m2/s and density of water 1000 kg/m3. |
| A. | 2.8*108 |
| B. | 2.8*105 |
| C. | 2800 |
| D. | 28000 |
| Answer» C. 2800 | |
| 3. |
A circular pipe of radius 7 cm is used for water flow transmission. This pipe is moulded into another pipe with a square cross-section keeping the length same. (Ignore the thickness of the pipe). Calculate the hydraulic diameter of the moulded pipe. (Take π = 22/7). |
| A. | 11 cm |
| B. | 7 cm |
| C. | 3.5 cm |
| D. | 22 cm |
| E. | . Calculate the hydraulic diameter of the moulded pipe. (Take π = 22/7).a) 11 cmb) 7 cmc) 3.5 cmd) 22 cm |
| Answer» B. 7 cm | |
| 4. |
When a problem states “The velocity of the water flow in a pipe is 20 m/s”, which of the following velocities is it talking about? |
| A. | RMS velocity |
| B. | Average velocity |
| C. | Absolute velocity |
| D. | Relative velocity |
| Answer» C. Absolute velocity | |
| 5. |
WHICH_OF_THE_FOLLOWING_FLOWS_HAVE_THE_HIGHEST_CRITICAL_REYNOLDS_NUMBER_(LOWER)??$ |
| A. | Flow in a pipe |
| B. | Flow between parallel plates |
| C. | Flow in an open channel |
| D. | Flow around spherical body |
| Answer» B. Flow between parallel plates | |
| 6. |
What can be the maximum diameter of the pipe for the water flow of velocity 1 m/s (ν = 10-6) to be laminar in nature? Assume Lower critical Reynolds number to be 2100?# |
| A. | 2.1 mm |
| B. | 21 mm |
| C. | 21 cm |
| D. | 0.21 mm |
| Answer» B. 21 mm | |
| 7. |
The flow through a circular pipe is laminar. Now, the fluid through the pipe is replaced with a more viscous fluid and passed through the pipe again with the same velocity. What can we say about the nature of this flow? |
| A. | The flow will become turbulent |
| B. | The flow will be a transition flow |
| C. | The flow will remain laminar |
| D. | The Reynolds number of the earlier flow is required to answer this question |
| Answer» D. The Reynolds number of the earlier flow is required to answer this question | |
| 8. |
The Reynolds number is found out for a flow in a circular pipe. This circular pipe is moulded into a square pipe, keeping length of the pipe same. Ignore the thickness of the pipe. The Reynolds number changes by __________ |
| A. | 57% decrease |
| B. | 57% increase |
| C. | 43% decrease |
| D. | 43% increase |
| Answer» C. 43% decrease | |
| 9. |
Water flows through a circular tube with a velocity of 2 m/s. The diameter of the pipe is 14 cm. Take kinematic viscosity of water 10-6 m2/s and density of water 1000 kg/m3. |
| A. | 2.8*10<sup>8</sup> |
| B. | 2.8*10<sup>5</sup> |
| C. | 2800 |
| D. | 28000 |
| Answer» C. 2800 | |
| 10. |
A circular pipe of radius 7 cm is used for water flow transmission. This pipe is moulded into another pipe with a square cross-section keeping the length same. (Ignore the thickness of the pipe). Calculate the hydraulic diameter of the moulded pipe. (Take π = 22/7).$ |
| A. | 11 cm |
| B. | 7 cm |
| C. | 3.5 cm |
| D. | 22 cm |
| Answer» B. 7 cm | |
| 11. |
How is Reynolds number defined as? |
| A. | Ratio of pressures in the inlet to the outlet of a pipe |
| B. | The product of velocity of the flow and the diameter of the pipe, divided by the kinematic viscosity of fluid |
| C. | The product of density of the fluid, velocity of the flow and the diameter of the pipe, divided by the dynamic viscosity of fluid |
| D. | Ratio of inertia force to viscous force |
| Answer» E. | |
| 12. |
Which of the factors primarily decide whether the flow in a circular pipe is laminar or turbulent? |
| A. | The Prandtl Number |
| B. | The Pressure gradient along the length of the pipe |
| C. | The dynamic viscosity coefficient |
| D. | The Reynolds Number |
| Answer» E. | |
| 13. |
When a problem states “The velocity of the water flow in a pipe is 20 m/s”, which of the following velocities is it talking about?$ |
| A. | RMS velocity |
| B. | Average velocity |
| C. | Absolute velocity |
| D. | Relative velocity |
| Answer» C. Absolute velocity | |
| 14. |
For a fully-developed pipe flow, how does the pressure vary with the length of the pipe? |
| A. | Linearly |
| B. | Parabolic |
| C. | Exponential |
| D. | Constant |
| Answer» B. Parabolic | |