MCQOPTIONS
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MCQOPTIONS
This section includes 15 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. |
A body through which all the incident radiations passes, is called |
| A. | Opaque body |
| B. | Black body |
| C. | Transparent body |
| D. | White body |
| Answer» D. White body | |
| 2. |
With respect to incident radiation, transmissivity varies with |
| A. | Time |
| B. | Temperature |
| C. | Surface area |
| D. | Wavelength |
| Answer» E. | |
| 3. |
Radiant energy with an intensity of 800 W/m2 strikes a flat plate normally. The absorptivity is thrice the reflectivity and twice the transmissivity. Determine the rate of transmission |
| A. | 155.47 W/m2 |
| B. | 145.47 W/m2 |
| C. | 135.47 W/m2 |
| D. | 125.47 W/m2 |
| Answer» C. 135.47 W/m2 | |
| 4. |
A polished metal pipe 5 cm outside diameter and 370 K temperature at the outer surface is exposed to ambient conditions at 295 K temperature. The emissivity of the surface is 0.2 and the convection coefficient of heat transfer is 11.35 W/m2 degree. Calculate the overall coefficient of heat transfer by the combined mode of convection and radiation |
| A. | 11.04 W/m2 degree |
| B. | 12.04 W/m2 degree |
| C. | 13.04 W/m2 degree |
| D. | 14.04 W/m2 degree |
| Answer» D. 14.04 W/m2 degree | |
| 5. |
Of the radiant energy 350W/m2 incident upon a surface 250W/m2 is absorbed, 60W/m2 is reflected and the remainder is transmitted through the surface. Workout the value for absorptivity for the surface material |
| A. | 0.113 |
| B. | 0.114 |
| C. | 0.115 |
| D. | 0.116 |
| Answer» D. 0.116 | |
| 6. |
WITH_RESPECT_TO_INCIDENT_RADIATION,_TRANSMISSIVITY_VARIES_WITH?$ |
| A. | Time |
| B. | Temperature |
| C. | Surface area |
| D. | Wavelength |
| Answer» E. | |
| 7. |
A body through which all the incident radiations passes, is called$ |
| A. | Opaque body |
| B. | Black body |
| C. | Transparent body |
| D. | White body |
| Answer» D. White body | |
| 8. |
Radiant energy with an intensity of 800 W/m2 strikes a flat plate normally. The absorptivity is thrice the reflectivity and twice the transmissivity. Determine the rate of transmissio? |
| A. | 155.47 W/m<sup>2</sup> |
| B. | 145.47 W/m<sup>2</sup> |
| C. | 135.47 W/m<sup>2</sup> |
| D. | 125.47 W/m<sup>2</sup> |
| Answer» C. 135.47 W/m<sup>2</sup> | |
| 9. |
A polished metal pipe 5 cm outside diameter and 370 K temperature at the outer surface is exposed to ambient conditions at 295 K temperature. The emissivity of the surface is 0.2 and the convection coefficient of heat transfer is 11.35 W/m2 degree. Calculate the overall coefficient of heat transfer by the combined mode of convection and radiation |
| A. | 11.04 W/m<sup>2</sup> degree |
| B. | 12.04 W/m<sup>2</sup> degree |
| C. | 13.04 W/m<sup>2</sup> degree |
| D. | 14.04 W/m<sup>2</sup> degree |
| Answer» D. 14.04 W/m<sup>2</sup> degree | |
| 10. |
Transmissivity is defined as |
| A. | Fraction of total energy transmitted by the body |
| B. | Fraction of total energy reflected by the body |
| C. | Fraction of total energy absorbed by the body |
| D. | Fraction of total energy absorbed and radiated by the body |
| Answer» B. Fraction of total energy reflected by the body | |
| 11. |
What is the wavelength band of gamma rays? |
| A. | 1 * 10<sup> -7</sup> to 4 * 10<sup> -4</sup> micron meter |
| B. | 2 * 10<sup> -7</sup> to 2.4 * 10<sup> -4</sup> micron meter |
| C. | 3 * 10<sup> -7</sup> to 3.4 * 10<sup> -4</sup> micron meter |
| D. | 4 * 10<sup> -7</sup> to 1.4 * 10<sup> -4</sup> micron meter |
| Answer» E. | |
| 12. |
A cavity with a small hole will always behave as a |
| A. | White body |
| B. | Transparent body |
| C. | Black body |
| D. | Opaque body |
| Answer» D. Opaque body | |
| 13. |
Transmissivity can also be defined as a ratio of transmitted radiation to that of incident energy flow. |
| A. | True |
| B. | False |
| Answer» C. | |
| 14. |
Of the radiant energy 350W/m2 incident upon a surface 250W/m2 is absorbed, 60W/m2 is reflected and the remainder is transmitted through the surface. Workout the value for absorptivity for the surface material |
| A. | 0.113 |
| B. | 0.114 |
| C. | 0.115 |
| D. | 0.116 |
| Answer» D. 0.116 | |
| 15. |
The value of transmissivity may vary from |
| A. | 0-1 |
| B. | 1-2 |
| C. | 3-4 |
| D. | 4-5 |
| Answer» B. 1-2 | |