Heat and Mass Transfer According to Stefan's law, the total radiation from a black body per second per unit area is proportional to T5 T2 Absolute temperature T T5 T2 Absolute temperature T ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be One Four Three Two One Four Three Two ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The unit of Stefan Boltzmann constant is watt/cm4 °K watt/cm3 °K watt/cm2 °K⁴ watt2/cm °K⁴ watt/cm4 °K watt/cm3 °K watt/cm2 °K⁴ watt2/cm °K⁴ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The amount of heat flow through a body by conduction is All of these Directly proportional to the surface area of the body Directly proportional to the temperature difference on the two faces of the body Dependent upon the material of the body All of these Directly proportional to the surface area of the body Directly proportional to the temperature difference on the two faces of the body Dependent upon the material of the body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Kirchhoff's law states that The wave length corresponding to the maximum energy is proportional to the absolute temperature None of these The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature None of these The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Absorptivity of a body will be equal to its emissivity At critical temperature When system is under thermal equilibrium At one particular temperature At all temperatures At critical temperature When system is under thermal equilibrium At one particular temperature At all temperatures ANSWER DOWNLOAD EXAMIANS APP