Heat and Mass Transfer The critical thickness of insulation for a sphere is k/h₀ h₀/2k 2k/h₀ h₀/k k/h₀ h₀/2k 2k/h₀ h₀/k ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat of sun reaches to us according to Conduction Radiation Convection None of these Conduction Radiation Convection None of these 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 According to Stefan Boltzmann law, ideal radiators emit radiant energy at a rate proportional to Absolute temperature Fourth power of absolute temperature Square of temperature Fourth power of temperature Absolute temperature Fourth power of absolute temperature Square of temperature Fourth power of temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The insulation ability of an insulator with the presence of moisture would Increase Remain unaffected May increase/decrease depending on temperature and thickness of insulation Decrease Increase Remain unaffected May increase/decrease depending on temperature and thickness of insulation Decrease ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Absorptivity of a body will be equal to its emissivity At one particular temperature At all temperatures At critical temperature When system is under thermal equilibrium At one particular temperature At all temperatures At critical temperature When system is under thermal equilibrium ANSWER DOWNLOAD EXAMIANS APP