Heat and Mass Transfer Fouling factor is used 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 None of these In heat exchanger design as a safety factor ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in S.I. units is Option (B) and (C) above J/m² sec J/m °K sec W/m °K Option (B) and (C) above J/m² sec J/m °K sec W/m °K ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick cylinder (Q) is given by (where T₁ = Higher temperature, T₂ = Lower temperature, r₁ = Inside radius, r₂ = Outside radius, l = Length of cylinder, and k = Thermal conductivity) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of the energy absorbed by the body to total energy falling on it is called Emissivity Absorptive power Absorptivity Emissive power Emissivity Absorptive power Absorptivity Emissive power 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 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 Depending on the radiating properties, a body will be white when(Where a = absorptivity, p = reflectivity, x = transmissivity) P = 0, x = 1 and a = 0 P=1, T = 0 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P = 0, x = 1 and a = 0 P=1, T = 0 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 ANSWER DOWNLOAD EXAMIANS APP