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 = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred by molecular collision, it is referred to as heat transfer by Convection Radiation Scattering Conduction Convection Radiation Scattering Conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water in general with rise in temperature Remain constant May increase or decrease depending on temperature Increases Decreases Remain constant May increase or decrease depending on temperature Increases Decreases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is Equal to one Greater than one Less than one Equal to Nusselt number Equal to one Greater than one Less than one Equal to Nusselt number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When α is absorptivity, ρ is reflectivity and τ is transmissivity, then for a diathermanous body, α = 0, ρ = 0 and τ = 1 α = 1, ρ = 0 and τ = 0 α = 0, ρ = 1 and τ = 0 α + ρ = 1 and τ = 0 α = 0, ρ = 0 and τ = 1 α = 1, ρ = 0 and τ = 0 α = 0, ρ = 1 and τ = 0 α + ρ = 1 and τ = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Film coefficient is defined as the ratio of Thickness of film of fluid to the thermal conductivity Temperature drop through the films of fluids to the thickness of film of fluids Thickness of film of fluid to the temperature drop through the films of fluids Thermal conductivity to the equivalent thickness of the film of fluid Thickness of film of fluid to the thermal conductivity Temperature drop through the films of fluids to the thickness of film of fluids Thickness of film of fluid to the temperature drop through the films of fluids Thermal conductivity to the equivalent thickness of the film of fluid ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS