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 1 =-1/3 =-2/3 -1 1 =-1/3 =-2/3 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following would lead to a reduction in thermal resistance? In convection, stirring of the fluid and cleaning the heating surface. In radiation, increasing the temperature and reducing the emissivity. All of these In conduction, reduction in the thickness of the material and an increase in thermal conductivity. In convection, stirring of the fluid and cleaning the heating surface. In radiation, increasing the temperature and reducing the emissivity. All of these In conduction, reduction in the thickness of the material and an increase in thermal conductivity. ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat transfer in liquid and gases takes place by Conduction Conduction and convection Convection Radiation Conduction Conduction and convection Convection Radiation 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 Thermal conductivity of wood depends on Moisture All of these Temperature Density Moisture All of these Temperature Density ANSWER DOWNLOAD EXAMIANS APP