Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) 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 Emissivity of a white polished body in comparison to a black body is Lower Higher Same Depends upon the shape of body Lower Higher Same Depends upon the shape of body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fouling factor is used None of these In heat exchanger design as a safety factor In case of Newtonian fluids When a liquid exchanges heat with a gas None of these In heat exchanger design as a safety factor In case of Newtonian fluids When a liquid exchanges heat with a gas ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The process of heat transfer from one particle of the fluid to another by the actual movement of the fluid particles due to difference of density caused by temperature of the particle is known as Radiation Conduction Free convection Forced convection Radiation Conduction Free convection Forced convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical thickness of insulation for a sphere is 2k/h₀ k/h₀ h₀/2k h₀/k 2k/h₀ k/h₀ h₀/2k h₀/k ANSWER DOWNLOAD EXAMIANS APP