Heat and Mass Transfer When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a Opaque body White body Grey body Black body Opaque body White body Grey body Black body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The expression Q = ρ AT4 is called Stefan-Boltzmann equation Fourier equation Newton Reichmann equation Joseph-Stefan equation Stefan-Boltzmann equation Fourier equation Newton Reichmann equation Joseph-Stefan equation ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The value of the wave length for maximum emissive power is given by Kirchhoff’s law Stefan’s law Wine’s law Planck’s law Kirchhoff’s law Stefan’s law Wine’s law Planck’s law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical thickness of insulation for a sphere is h₀/2k 2k/h₀ k/h₀ h₀/k h₀/2k 2k/h₀ k/h₀ h₀/k ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law. Directly proportional to Inversely proportional to None of these Equal to Directly proportional to Inversely proportional to None of these Equal to ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of wood depends on All of these Moisture Density Temperature All of these Moisture Density Temperature ANSWER DOWNLOAD EXAMIANS APP
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