McqMate
| Q. |
Pick out the wrong statement. |
| A. | In process heat exchangers, saturated steam is preferred over the superheated steam |
| B. | The maximum is the emissive power of a surface at a temperature T1 occurs at a wavelength of λ1. If the surface temperature is halved, the maximum in the emissive power would occur at a wavelength of 0.5 λ1 |
| C. | When a vertical plate is heated in infinite air environmental under natural convection conditions, the velocity profile in air, normal to the plate, exhibits a maximum |
| D. | A body at 925 K emits an energy of 1.42 x 1011ζW/m2 (ζ is the Stefan-Boltzmann constant) in the wavelength band between 3 μm to 4 μm. The fraction of this energy in the total energy emitted over the entire wavelength range is equal to emissivity |
| Answer» B. The maximum is the emissive power of a surface at a temperature T1 occurs at a wavelength of λ1. If the surface temperature is halved, the maximum in the emissive power would occur at a wavelength of 0.5 λ1 | |
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