Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 81 3 270 9 81 3 270 9 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer 40% of incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is 0.45 0.75 0.4 0.55 0.45 0.75 0.4 0.55 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Film coefficient is defined as Inside diameter of tube Film coefficient × Inside diameter Thermal conductivity Equivalent thickness of film Thermal conductivity Equivalent thickness of film Specific heat × Viscosity Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity Film coefficient × Inside diameter Thermal conductivity Equivalent thickness of film Thermal conductivity Equivalent thickness of film Specific heat × Viscosity Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is Inversely proportional to density of substance Inversely proportional to specific heat All of these Directly proportional to the thermal conductivity Inversely proportional to density of substance Inversely proportional to specific heat All of these Directly proportional to the thermal conductivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number is the ratio of Kinematic viscosity to thermal diffusivity None of these Energy transferred by convection to that by conduction Inertia force to viscous force Kinematic viscosity to thermal diffusivity None of these Energy transferred by convection to that by conduction Inertia force to viscous force ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred by molecular collision, it is referred to as heat transfer by Conduction Scattering Radiation Convection Conduction Scattering Radiation Convection ANSWER DOWNLOAD EXAMIANS APP