Heat and Mass Transfer According to Stefan Boltzmann law, ideal radiators emit radiant energy at a rate proportional to 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 Absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be Four Three One Two Four Three One Two ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by Radiation Free convection Convection Forced convection Radiation Free convection Convection Forced convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Stefan Boltzmann law is applicable for heat transfer by Radiation Conduction Conduction and radiation combined Convection Radiation Conduction Conduction and radiation combined Convection 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 = 1, ρ = 0 and τ = 0 α + ρ = 1 and τ = 0 α = 0, ρ = 0 and τ = 1 α = 0, ρ = 1 and τ = 0 α = 1, ρ = 0 and τ = 0 α + ρ = 1 and τ = 0 α = 0, ρ = 0 and τ = 1 α = 0, ρ = 1 and τ = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Kirchoff's law, the ratio of emissive power to absorptivity for all bodies is equal to the emissive power of a Red hot body Brilliant white polished body Black body Grey body Red hot body Brilliant white polished body Black body Grey body ANSWER DOWNLOAD EXAMIANS APP