Heat and Mass Transfer Heat transfer by radiation mainly depends upon Kind and extent of its surface Nature of the body All of these Its temperature Kind and extent of its surface Nature of the body All of these Its temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 3 81 270 9 3 81 270 9 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal diffusivity is m²/hr kcal/m. hr °C kcal/m² hr m²/hr °C m²/hr kcal/m. hr °C kcal/m² hr m²/hr °C 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 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 = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following is the case of heat transfer by radiation? Cooling of parts in furnace Heating of building Blast furnace Heat received by a person from fireplace Cooling of parts in furnace Heating of building Blast furnace Heat received by a person from fireplace ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS