Heat and Mass Transfer Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by Free convection Forced convection Radiation Convection Free convection Forced convection Radiation Convection 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 Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature 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 Two One Three Four Two One Three Four ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In heat transfer, conductance equals conductivity (kcal/hr/sq.m/°C/cm) divided by K.cal (heat) Sq. m (area) Hr (time) °C (temperature) K.cal (heat) Sq. m (area) Hr (time) °C (temperature) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Film coefficient is defined as Inside diameter of tube Equivalent thickness of film Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity Thermal conductivity Equivalent thickness of film Specific heat × Viscosity Film coefficient × Inside diameter Thermal conductivity Equivalent thickness of film Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity Thermal conductivity Equivalent thickness of film Specific heat × Viscosity Film coefficient × Inside diameter Thermal conductivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Emissivity of a white polished body in comparison to a black body is Higher Same Lower Depends upon the shape of body Higher Same Lower Depends upon the shape of body ANSWER DOWNLOAD EXAMIANS APP
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