MCQOPTIONS
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MCQOPTIONS
This section includes 6 Mcqs, each offering curated multiple-choice questions to sharpen your Heat Transfer Questions and Answers knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The energy radiated out decreases with increases in α and becomes zero at an angle of |
| A. | 45 |
| B. | 30 |
| C. | 0 |
| D. | 90 |
| Answer» E. | |
| 2. |
A black body of 0.2 m2 area has an effective temperature of 800 K. Calculate the intensity of normal radiations |
| A. | 1234.65 W/m2 sr |
| B. | 7396.28 W/m2 sr |
| C. | 3476.74 W/m2 sr |
| D. | 8739.43 W/m2 sr |
| Answer» C. 3476.74 W/m2 sr | |
| 3. |
Consider a deep-space probe constructed as 1 m diameter polished aluminum sphere. Estimate the equilibrium temperature that the probe reaches if the solar energy received is 300 W/m2. For solar radiation, absorptivity of aluminum is 0.3 and the average emissivity appropriate for aluminum at low temperature is 0.04 |
| A. | 415.67 K |
| B. | 315.67 K |
| C. | 215.67 K |
| D. | 115.67 K |
| Answer» C. 215.67 K | |
| 4. |
A small surface emits diffusively, and measurements indicate that the total intensity associated with emission in the normal direction I n = 6500 W/square m sr. The emitted radiation is intercepted by three surfaces. Mark calculations for intensity associated with emission |
| A. | 3500 W/m2 sr |
| B. | 4500 W/m2 sr |
| C. | 5500 W/m2 sr |
| D. | 6500 W/m2 sr |
| Answer» E. | |
| 5. |
The intensity of normal radiation I n is how much times the emissive power? |
| A. | 1/π |
| B. | 2/ π |
| C. | 3/ π |
| D. | 4/ π |
| Answer» B. 2/ π | |
| 6. |
If I n denotes the normal intensity and I α represents the intensity at angle α, then |
| A. | I α = 2 I n cos α |
| B. | I α = 3 I n cos α |
| C. | I α = 4 I n cos α |
| D. | I α = I n cos α |
| Answer» E. | |