Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 3 9 81 270 3 9 81 270 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat conducted through per unit area and unit thick face per unit time when temperature difference between opposite faces is unity, is called Thermal resistance Temperature gradient Thermal coefficient Thermal conductivity Thermal resistance Temperature gradient Thermal coefficient Thermal conductivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be 2 k₁ k₂/ (k₁ + k₂) k₁ k₂ (k₁ + k₂)/ k₁ k₂ (k₁ + k₂) 2 k₁ k₂/ (k₁ + k₂) k₁ k₂ (k₁ + k₂)/ k₁ k₂ (k₁ + k₂) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following property of air does not increase with rise in temperature? Density Thermal conductivity Thermal diffusivity Dynamic viscosity Density Thermal conductivity Thermal diffusivity Dynamic viscosity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity) RN = ρ V l /μ RN = hl/k RN = μ cp/k RN = V²/t.cp RN = ρ V l /μ RN = hl/k RN = μ cp/k RN = V²/t.cp ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat of sun reaches to us according to Radiation Convection Conduction None of these Radiation Convection Conduction None of these ANSWER DOWNLOAD EXAMIANS APP
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