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 (k₁ + k₂) 2 k₁ k₂/ (k₁ + k₂) k₁ k₂ (k₁ + k₂)/ k₁ k₂ (k₁ + k₂) 2 k₁ k₂/ (k₁ + k₂) k₁ k₂ (k₁ + k₂)/ k₁ k₂ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of air with rise in temperature May increase or decrease depending on temperature Remain constant Decreases Increases May increase or decrease depending on temperature Remain constant Decreases Increases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In free convection heat transfer, Nusselt number is function of Grashoff number and Reynold number Grashoff number and Prandtl number Prandtl number and Reynold number Grashoff number, Prandtl number and Reynold number Grashoff number and Reynold number Grashoff number and Prandtl number Prandtl number and Reynold number Grashoff number, Prandtl number and Reynold number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal diffusivity is kcal/m. hr °C m²/hr m²/hr °C kcal/m² hr kcal/m. hr °C m²/hr m²/hr °C kcal/m² hr ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Absorptivity of a body will be equal to its emissivity At one particular temperature At all temperatures When system is under thermal equilibrium At critical temperature At one particular temperature At all temperatures When system is under thermal equilibrium At critical temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body. This statement is known as Wien's law Kirchhoff's law Stefan's law Planck's law Wien's law Kirchhoff's law Stefan's law Planck's law ANSWER DOWNLOAD EXAMIANS APP