MCQOPTIONS
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MCQOPTIONS
This section includes 13 Mcqs, each offering curated multiple-choice questions to sharpen your Heat Transfer knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The boundary layer thickness is taken to be at a distance from the plate surface to a point at which the velocity is given by |
| A. | u = 0.99 U INFINITY |
| B. | u = 0.75 U INFINITY |
| C. | u = 0.50 U INFINITY |
| D. | u = 0.33 U INFINITY |
| Answer» B. u = 0.75 U INFINITY | |
| 2. |
The entrance length required for the flow to become fully-developed turbulent flow is dependent on(i) Surface finish(ii) Downstream conditions(iii) Fluid propertiesIdentify the correct answer |
| A. | ii and iii |
| B. | i and iii |
| C. | i, ii and iii |
| D. | i and ii |
| Answer» D. i and ii | |
| 3. |
Consider the diagram given below and identify the correct option |
| A. | The velocity gradient is zero everywhere |
| B. | The velocity profile changes at every instant of time |
| C. | Boundary layers from the pipe walls meet the pipe anywhere |
| D. | Thickness of the boundary layer is limited to the pipe radius |
| Answer» E. | |
| 4. |
The free stream undisturbed flow has a uniform velocity U INFINITY in the |
| A. | X-direction |
| B. | Y-direction |
| C. | Z-direction |
| D. | Any direction |
| Answer» B. Y-direction | |
| 5. |
THE_BOUNDARY_LAYER_THICKNESS_IS_TAKEN_TO_BE_AT_A_DISTANCE_FROM_THE_PLATE_SURFACE_TO_A_POINT_AT_WHICH_THE_VELOCITY_IS_GIVEN_BY?$ |
| A. | u = 0.99 U <sub>INFINITY</sub> |
| B. | u = 0.75 U <sub>INFINITY</sub> |
| C. | u = 0.50 U <sub>INFINITY</sub> |
| D. | u = 0.33 U <sub>INFINITY</sub> |
| Answer» B. u = 0.75 U <sub>INFINITY</sub> | |
| 6. |
What is the value of the thickness of the boundary layer at leading edge of the plate? |
| A. | 0.33 |
| B. | 1 |
| C. | 0.5 |
| D. | 0 |
| Answer» E. | |
| 7. |
The entrance length required for the flow to become fully-developed turbulent flow is dependent on |
| A. | Surface finish |
| B. | Downstream conditions |
| C. | Fluid properties |
| Answer» D. | |
| 8. |
The transition from laminar to turbulent pattern of flow occurs at values of Reynolds number between |
| A. | 1000-2000 |
| B. | 300000-500000 |
| C. | 500000-700000 |
| D. | 35750-45678 |
| Answer» C. 500000-700000 | |
| 9. |
The pattern of flow in the boundary layer is judged by the |
| A. | Reynolds number |
| B. | Fourier number |
| C. | Peclet number |
| D. | Grashof number |
| Answer» B. Fourier number | |
| 10. |
The conditions for flow beyond the boundary layer and its outer edge are |
| A. | d u/d y = 0 and u = U<sub> 0</sub> |
| B. | d u/d y = Infinity and u = U<sub> INFINITY</sub> |
| C. | d u/d y = 1 and u = U<sub> 0</sub> |
| D. | d u/d y = 0 and u = U<sub> INFINITY</sub> |
| Answer» E. | |
| 11. |
The thin layer where velocity changes continuously is called |
| A. | Differential layer |
| B. | Thermal boundary layer |
| C. | Hydrodynamic boundary layer |
| D. | Velocity distribution layer |
| Answer» D. Velocity distribution layer | |
| 12. |
The free stream undisturbed flow has a uniform velocity U INFINITY in the |
| A. | X-direction |
| B. | Y-direction |
| C. | Z-direction |
| D. | Any direction |
| Answer» B. Y-direction | |
| 13. |
The concept of the hydrodynamic boundary layer was first suggested by |
| A. | Isaac Newton |
| B. | Ludwig Prandtl |
| C. | Rodridge |
| D. | Fourier |
| Answer» C. Rodridge | |