MCQOPTIONS
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MCQOPTIONS
This section includes 12 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. |
For transient flow, the value of Reynolds number may vary between |
| A. | 1450-9870 |
| B. | 1200-4500 |
| C. | 2300-6000 |
| D. | 6000-9000 |
| Answer» D. 6000-9000 | |
| 2. |
Heat is being transferred by convection from water at 48 degree Celsius to glass plate whose surface is exposed to water at 40 degree Celsius. The thermal conductivity of water is 0.6 W/m K and the thermal conductivity of glass is 1.2 W/m K. The spectral gradient of temperature in the water at the water glass interface is 10 -4 K/m. The heat transfer coefficient in W/m2 K is |
| A. | 0 |
| B. | 750 |
| C. | 6.0 |
| D. | 4.8 |
| Answer» C. 6.0 | |
| 3. |
Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degree Celsius. The flowing air has a thermal conductivity 0.028 W/m K, kinematic viscosity 16.95 * 10 -6 m2/s and from empirical correlations the Nusselt number has been approximated to be 425. Find out the flow Reynolds number |
| A. | 1.1719 * 10 6 |
| B. | 2.1719 * 10 6 |
| C. | 0.1719 * 10 6 |
| D. | 4.1719 * 10 6 |
| Answer» D. 4.1719 * 10 6 | |
| 4. |
For_transient_flow,_the_value_of_Reynolds_number_may_vary_between$ |
| A. | 1450-9870 |
| B. | 1200-4500 |
| C. | 2300-6000 |
| D. | 6000-9000 |
| Answer» D. 6000-9000 | |
| 5. |
What is the value of convective coefficient of air and superheated steam in case of forced convection? |
| A. | 30-900 W/m<sup>2</sup> K |
| B. | 30-700 W/m<sup>2</sup> K |
| C. | 30-300 W/m<sup>2</sup> K |
| D. | 30-400 W/m<sup>2</sup> K |
| Answer» D. 30-400 W/m<sup>2</sup> K | |
| 6. |
For turbulent flow, Reynolds number must be |
| A. | Less than 5000 |
| B. | Equal to 6000 |
| C. | Less than 6000 |
| D. | Greater than 6000 |
| Answer» E. | |
| 7. |
For laminar flow, Reynolds number should be |
| A. | Less than 2300 |
| B. | Equal to 2300 |
| C. | Greater than 2300 |
| D. | Less than 4300 |
| Answer» B. Equal to 2300 | |
| 8. |
Consider the above problem, find the convective heat flow coefficient |
| A. | 24.71 W/m<sup>2</sup> K |
| B. | 34.71 W/m<sup>2</sup> K |
| C. | 44.71 W/m<sup>2</sup> K |
| D. | 54.71 W/m<sup>2</sup> K |
| Answer» C. 44.71 W/m<sup>2</sup> K | |
| 9. |
Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degree Celsius. The flowing air has a thermal conductivity 0.028 W/m K, kinematic viscosity 16.95 * 10 -6 m2/s and from empirical correlations the Nusselt number has been approximated to be 425. Find out the flow Reynolds number |
| A. | 1.1719 * 10 <sup>6</sup> |
| B. | 2.1719 * 10 <sup>6</sup> |
| C. | 0.1719 * 10 <sup>6</sup> |
| D. | 4.1719 * 10 <sup>6</sup> |
| Answer» D. 4.1719 * 10 <sup>6</sup> | |
| 10. |
Reynolds number is given by the quantity |
| A. | p V l/δ |
| B. | 2 p V l/δ |
| C. | 3 p V l/δ |
| D. | 4 p V l/δ |
| Answer» B. 2 p V l/‚âà√≠¬¨‚Ä¢ | |
| 11. |
Velocity within the given fields would be similar in magnitude, direction and turbulence pattern when |
| A. | Nusselt number are different |
| B. | Nusselt number are same |
| C. | Reynolds number are different |
| D. | Reynolds number are same |
| Answer» E. | |
| 12. |
The ratio of inertia force to viscous force is known as |
| A. | Grashof number |
| B. | Reynolds number |
| C. | Fourier number |
| D. | Nusselt number |
| Answer» C. Fourier number | |