Heat and Mass Transfer A perfect black body is one which Reflects all heat Absorbs heat radiations of all wave lengths falling on it Transmits all heat radiations Is black in colour Reflects all heat Absorbs heat radiations of all wave lengths falling on it Transmits all heat radiations Is black in colour ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer LMTD in case of counter flow heat exchanger as compared to parallel flow heat exchanger is Lower Depends on the area of heat exchanger Same Higher Lower Depends on the area of heat exchanger Same Higher ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan's law, the total radiation from a black body per second per unit area is proportional to T2 Absolute temperature T5 T T2 Absolute temperature T5 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 Three Four Two One Three Four Two One ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In convection heat transfer from hot flue gases to water tube, even though flow may be turbulent, a laminar flow region (boundary layer of film) exists close to the tube. The heat transfer through this film takes place by Convection Conduction Radiation Both convection and conduction Convection Conduction Radiation Both convection and conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following is expected to have highest thermal conductivity? Melting ice Steam Water Solid ice Melting ice Steam Water Solid ice ANSWER DOWNLOAD EXAMIANS APP