Heat and Mass Transfer According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the Square of the absolute temperature Absolute temperature Fourth power of the absolute temperature Cube of the absolute temperature Square of the absolute temperature Absolute temperature Fourth power of the absolute temperature Cube of the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called Emissivity Emissive power Absorptive power None of these Emissivity Emissive power Absorptive power None of these 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 =-1/3 -1 =-2/3 1 =-1/3 -1 =-2/3 1 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat is transferred by all three modes of transfer, viz. conduction, convection and radiation in Boiler Refrigerator condenser coils Electric heater Steam condenser Boiler Refrigerator condenser coils Electric heater Steam condenser ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Log mean temperature difference in case of counter flow compared to parallel flow will be Same More Depends on other factors Less Same More Depends on other factors Less ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as Transmissivity Emissivity Intensity of radiation Reflectivity Transmissivity Emissivity Intensity of radiation Reflectivity ANSWER DOWNLOAD EXAMIANS APP