Heat and Mass Transfer The radiation emitted by a black body is known as Total radiation Black radiation All of these Full radiation Total radiation Black radiation All of these Full radiation ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Sensible heat is the heat required to Increase the temperature of a liquid of vapour Change vapour into liquid Convert water into steam and superheat it Change liquid into vapour Increase the temperature of a liquid of vapour Change vapour into liquid Convert water into steam and superheat it Change liquid into vapour 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 = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁) Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Prevost theory of heat exchange Heat transfer by radiation requires no medium It is impossible to transfer heat from low temperature source to t high temperature source All bodies above absolute zero emit radiation Heat transfer in most of the cases takes place by combination of conduction, convection and radiation Heat transfer by radiation requires no medium It is impossible to transfer heat from low temperature source to t high temperature source All bodies above absolute zero emit radiation Heat transfer in most of the cases takes place by combination of conduction, convection and radiation ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the Fourth power of the absolute temperature Absolute temperature Cube of the absolute temperature Square of the absolute temperature Fourth power of the absolute temperature Absolute temperature Cube of the absolute temperature Square of the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a Grey body Black body White body Opaque body Grey body Black body White body Opaque body ANSWER DOWNLOAD EXAMIANS APP
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