Define emissivity and absorptivity. What is Kirchhoff’s law of radiation?
What will be an ideal response?
Emissivity is the ratio of the radiation emitted by a surface to the radiation emitted by a blackbody at the same temperature. Absorptivity is the fraction of radiation incident on a surface that is absorbed by the surface. The Kirchhoff's law of radiation states that the emissivity and the absorptivity of a surface are equal at the same temperature and wavelength.
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Define a turbine.
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A) 10-12 weeks B) 12-16 weeks C) 8-12 weeks D) 12-18 weeks
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A. Technician A only B. Technician B only C. Both Technicians A and B D. Neither Technician A nor B
What are enamel coatings? ?
What will be an ideal response?