Heat and Mass Transfer In counter current flow heat exchanger, the logarithmic temperature difference between the fluids is ________ as compared to parallel flow heat exchanger. Greater None of these Less Same Greater None of these Less Same ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in M.K.S. units is K cal/hr m² °C K cal/kg m² °C K calm/hr °C K cal m/hr m² °C K cal/hr m² °C K cal/kg m² °C K calm/hr °C K cal m/hr m² °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Kirchhoff's law states that 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 None of these The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature 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 None of these The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature 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 (k₁ + k₂)/ k₁ k₂ 2 k₁ k₂/ (k₁ + k₂) (k₁ + k₂) k₁ k₂ (k₁ + k₂)/ k₁ k₂ 2 k₁ k₂/ (k₁ + k₂) (k₁ + k₂) k₁ k₂ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 60°C 66.7°C 20°C 40°C 60°C 66.7°C 20°C 40°C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following property of air does not increase with rise in temperature? Thermal diffusivity Thermal conductivity Dynamic viscosity Density Thermal diffusivity Thermal conductivity Dynamic viscosity Density ANSWER DOWNLOAD EXAMIANS APP
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