Heat and Mass Transfer Thermal conductivity of water at 20°C is of the order of 0.23 0.51 0.42 0.1 0.23 0.51 0.42 0.1 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat is transferred by conduction, convection and radiation in Condensation of steam in condenser Boiler furnaces Melting of ice None of these Condensation of steam in condenser Boiler furnaces Melting of ice None of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A grey body is one whose absorptivity Varies with wavelength of the incident ray Varies with temperature Is equal to its emissivity Does not vary with temperature and. wavelength of the incident ray Varies with wavelength of the incident ray Varies with temperature Is equal to its emissivity Does not vary with temperature and. wavelength of the incident ray ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when (Where a = absorptivity, p = reflectivity, x = transmissivity) P = 0, x= 1, and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P=1, x = 0, and a = 0 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 (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) 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) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The concept of overall coefficient of heat transfer is used in heat transfer problems of Convection Radiation Conduction and convection Conduction Convection Radiation Conduction and convection Conduction ANSWER DOWNLOAD EXAMIANS APP