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 Absorptive power None of these Emissive power Emissivity Absorptive power None of these Emissive power Emissivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The unit of overall coefficient of heat transfer is kcal/m hr °C kcal/m² hr °C kcal/hr °C kcal/m² kcal/m hr °C kcal/m² hr °C kcal/hr °C kcal/m² ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water in general with rise in temperature Increases May increase or decrease depending on temperature Decreases Remain constant Increases May increase or decrease depending on temperature Decreases Remain constant ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Emissivity of a white polished body in comparison to a black body is Higher Depends upon the shape of body Same Lower Higher Depends upon the shape of body Same Lower ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law. Equal to None of these Directly proportional to Inversely proportional to Equal to None of these Directly proportional to Inversely proportional to ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 20°C 66.7°C 40°C 60°C 20°C 66.7°C 40°C 60°C ANSWER DOWNLOAD EXAMIANS APP