Heat and Mass Transfer Kirchhoff's law states that None of these The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature None of these The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature The wave length corresponding to the maximum energy is proportional to the absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The highest thermal diffusivity is of Lead Iron Concrete Wood Lead Iron Concrete Wood ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The value of the wave length for maximum emissive power is given by Wine’s law Stefan’s law Planck’s law Kirchhoff’s law Wine’s law Stefan’s law Planck’s law Kirchhoff’s law 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 Free convection flow depends on Coefficient of viscosity Density All of these Gravitational force Coefficient of viscosity Density All of these Gravitational force ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity is a All of these Dimensionless parameter Function of temperature Physical property of a substance All of these Dimensionless parameter Function of temperature Physical property of a substance ANSWER DOWNLOAD EXAMIANS APP