Heat and Mass Transfer In case of liquids and gases, the heat transfer takes place according to Radiation Convection Conduction None of these Radiation Convection Conduction 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 = (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 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number is the ratio of Inertia force to viscous force None of these Energy transferred by convection to that by conduction Kinematic viscosity to thermal diffusivity Inertia force to viscous force None of these Energy transferred by convection to that by conduction Kinematic viscosity to thermal diffusivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In a heat exchanger with one fluid evaporating or condensing, the surface area required is least in Parallel flow Counter flow Cross flow All of these Parallel flow Counter flow Cross flow All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The value of the wave length for maximum emissive power is given by Stefan’s law Planck’s law Kirchhoff’s law Wine’s law Stefan’s law Planck’s law Kirchhoff’s law Wine’s law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan Boltzmann law, ideal radiators emit radiant energy at a rate proportional to Fourth power of temperature Fourth power of absolute temperature Square of temperature Absolute temperature Fourth power of temperature Fourth power of absolute temperature Square of temperature Absolute temperature ANSWER DOWNLOAD EXAMIANS APP