Heat and Mass Transfer Absorptivity of a body will be equal to its emissivity At all temperatures At one particular temperature At critical temperature When system is under thermal equilibrium At all temperatures At one particular temperature At critical temperature When system is under thermal equilibrium ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick cylinder (Q) is given by (where T₁ = Higher temperature, T₂ = Lower temperature, r₁ = Inside radius, r₂ = Outside radius, l = Length of cylinder, and k = Thermal conductivity) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] 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 Thickness Area Temperature Time Thickness Area Temperature Time ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thermal diffusivities for gases are generally More than those for solids More than those for liquids Less than those for liquids Dependent on the viscosity More than those for solids More than those for liquids Less than those for liquids Dependent on the viscosity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat flows from one body to other when they have Different temperatures Different atomic structure Different heat contents Different specific heat Different temperatures Different atomic structure Different heat contents Different specific heat ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat is closely related with Temperature Liquids Energy Entropy Temperature Liquids Energy Entropy ANSWER DOWNLOAD EXAMIANS APP
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