Heat and Mass Transfer In convection heat transfer from hot flue gases to water tube, even though flow may be turbulent, a laminar flow region (boundary layer of film) exists close to the tube. The heat transfer through this film takes place by Conduction Convection Radiation Both convection and conduction Conduction Convection Radiation Both convection and conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The concept of overall coefficient of heat transfer is used in case of heat transfer by Convection Conduction and convection Conduction Radiation Convection Conduction and convection Conduction Radiation 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= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat conducted through per unit area and unit thick face per unit time when temperature difference between opposite faces is unity, is called Thermal resistance Thermal conductivity Thermal coefficient Temperature gradient Thermal resistance Thermal conductivity Thermal coefficient Temperature gradient ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The radiation emitted by a black body is known as Total radiation Full radiation Black radiation All of these Total radiation Full radiation Black radiation All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Prevost theory of heat exchange It is impossible to transfer heat from low temperature source to t high temperature source Heat transfer by radiation requires no medium All bodies above absolute zero emit radiation Heat transfer in most of the cases takes place by combination of conduction, convection and radiation It is impossible to transfer heat from low temperature source to t high temperature source Heat transfer by radiation requires no medium All bodies above absolute zero emit radiation Heat transfer in most of the cases takes place by combination of conduction, convection and radiation ANSWER DOWNLOAD EXAMIANS APP