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 (T₁ - T₂)]/2.3 log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The amount of radiation mainly depends on All of these Nature of body Type of surface of body Temperature of body All of these Nature of body Type of surface of body Temperature of body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat transfer takes place as per Second law of the thermodynamics Zeroth law of thermodynamics First law of thermodynamic Kirchoff's law Second law of the thermodynamics Zeroth law of thermodynamics First law of thermodynamic Kirchoff's law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The highest thermal diffusivity is of Wood Lead Iron Concrete Wood Lead Iron Concrete ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following has least value of conductivity? Plastic Water Air Glass Plastic Water Air Glass ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Moisture would find its way into insulation by vapour pressure unless it is prevented by Less thermal conductivity insulator High vapour pressure A vapour seal High thickness of insulation Less thermal conductivity insulator High vapour pressure A vapour seal High thickness of insulation ANSWER DOWNLOAD EXAMIANS APP
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