Heat and Mass Transfer The value of Prandtl number for air is about 0.7 1.7 0.1 0.3 0.7 1.7 0.1 0.3 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat transfer by radiation mainly depends upon Nature of the body Kind and extent of its surface All of these Its temperature Nature of the body Kind and extent of its surface All of these Its temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical radius is the insulation radius at which the resistance to heat flow is Minimum None of these Maximum Zero Minimum None of these Maximum Zero 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 40°C 60°C 20°C 66.7°C 40°C 60°C 20°C 66.7°C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature Emissive power and absorptivity are constant for all bodies Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature Emissive power and absorptivity are constant for all bodies ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) X = 0, a + p = 0 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 P= 1, T = 0 and a = 0 X = 0, a + p = 0 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 P= 1, T = 0 and a = 0 ANSWER DOWNLOAD EXAMIANS APP