Heat and Mass Transfer Thermal conductivity of water _________ with rise in temperature. Decreases Increases Remain same May increase or decrease depending upon temperature Decreases Increases Remain same May increase or decrease depending upon temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Film coefficient is defined as the ratio of Thickness of film of fluid to the thermal conductivity Thermal conductivity to the equivalent thickness of the film of fluid Temperature drop through the films of fluids to the thickness of film of fluids Thickness of film of fluid to the temperature drop through the films of fluids Thickness of film of fluid to the thermal conductivity Thermal conductivity to the equivalent thickness of the film of fluid Temperature drop through the films of fluids to the thickness of film of fluids Thickness of film of fluid to the temperature drop through the films of fluids ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following has maximum value of thermal conductivity? Brass Aluminium Steel Copper Brass Aluminium Steel Copper ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of non-metallic amorphous solids with decrease in temperature Decreases May increase or decrease depending on temperature Increases Remain constant Decreases May increase or decrease depending on temperature Increases Remain constant ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The most commonly used method for the design of duct size is the Velocity reduction method Equal friction method Static regains method Dual or double method Velocity reduction method Equal friction method Static regains method Dual or double method 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 = [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)] Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) ANSWER DOWNLOAD EXAMIANS APP
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