Heat and Mass Transfer The thermal diffusivities for gases are generally Less than those for liquids Dependent on the viscosity More than those for liquids More than those for solids Less than those for liquids Dependent on the viscosity More than those for liquids More than those for solids ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In free convection heat transfer, Nusselt number is function of 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 Grashoff number and Reynold number Grashoff number and Prandtl number Prandtl number and Reynold number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A grey body is one whose absorptivity Does not vary with temperature and. wavelength of the incident ray Is equal to its emissivity Varies with temperature Varies with wavelength of the incident ray Does not vary with temperature and. wavelength of the incident ray Is equal to its emissivity Varies with temperature Varies with wavelength of the incident ray 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 (k₁ + k₂)/ k₁ k₂ 2 k₁ k₂/ (k₁ + k₂) (k₁ + k₂) k₁ k₂ (k₁ + k₂)/ k₁ k₂ 2 k₁ k₂/ (k₁ + k₂) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a Grey body Black body Opaque body White body Grey body Black body Opaque body White body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A cube at high temperature is immersed in a constant temperature bath. It loses heat from its top, bottom and side surfaces with heat transfer coefficients of h₁, h₂ and h₃ respectively. The average heat transfer coefficient for the cube is h₁ + h₂ + h₃ (h₁.h₂.h₃)1/3 None of these 1/h₁ + 1/h₂ + 1/h₃ h₁ + h₂ + h₃ (h₁.h₂.h₃)1/3 None of these 1/h₁ + 1/h₂ + 1/h₃ ANSWER DOWNLOAD EXAMIANS APP