Heat and Mass Transfer The emissivity for a black body is 1 0.75 0.5 1 0.75 0.5 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following is the case of heat transfer by radiation? Blast furnace Cooling of parts in furnace Heat received by a person from fireplace Heating of building Blast furnace Cooling of parts in furnace Heat received by a person from fireplace Heating of building ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A perfect black body is one which Is black in colour Transmits all heat radiations Absorbs heat radiations of all wave lengths falling on it Reflects all heat Is black in colour Transmits all heat radiations Absorbs heat radiations of all wave lengths falling on it Reflects all heat ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of the thickness of thermal boundary layer to the thickness of hydrodynamic boundary layer is equal to (Prandtl number) n, where n is equal to 1 =-2/3 =-1/3 -1 1 =-2/3 =-1/3 -1 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Wien’s law states that the wave length corresponding to ________ is proportional to the absolute temperature. None of these Maximum energy Both (A) and (B) Minimum energy None of these Maximum energy Both (A) and (B) Minimum energy ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 3 81 9 270 3 81 9 270 ANSWER DOWNLOAD EXAMIANS APP