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 Both convection and conduction Convection Radiation Conduction Both convection and conduction Convection Radiation ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute 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 depends on temperature Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute 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 depends on temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when(Where a = absorptivity, p = reflectivity, x = transmissivity) P = 0, x = 0 and a = 1 X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when (Where a = absorptivity, p = reflectivity, x = transmissivity) X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x = 0 and a = 1 P = 0, x= 1, and a = 0 X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x = 0 and a = 1 P = 0, x= 1, and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan's law, the total radiation from a black body per second per unit area is proportional to T2 T5 T Absolute temperature T2 T5 T Absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called None of these Absorptive power Emissivity Emissive power None of these Absorptive power Emissivity Emissive power ANSWER DOWNLOAD EXAMIANS APP