Heat and Mass Transfer According to Stefan's law, the total radiation from a black body per second per unit area is proportional to Absolute temperature T5 T T2 Absolute temperature T5 T T2 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water in general with rise in temperature Increases Remain constant Decreases May increase or decrease depending on temperature Increases Remain constant Decreases May increase or decrease depending on temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In regenerator type heat exchanger, heat transfer takes place by Generation of heat again and again Direct mixing of hot and cold fluids A complete separation between hot and cold fluids Flow of hot and cold fluids alternately over a surface Generation of heat again and again Direct mixing of hot and cold fluids A complete separation between hot and cold fluids Flow of hot and cold fluids alternately over a surface ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following property of air does not increase with rise in temperature? Thermal conductivity Thermal diffusivity Dynamic viscosity Density Thermal conductivity Thermal diffusivity Dynamic viscosity Density ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The total emissivity power is .defined as the total amount of radiation emitted by a black body per unit Area Thickness Time Temperature Area Thickness Time Temperature ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS