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 = = 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) Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)] Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The rate of energy emission from unit surface area through unit solid angle, along a normal to the surface, is known as Transmissivity Intensity of radiation Reflectivity Emissivity Transmissivity Intensity of radiation Reflectivity Emissivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In a heat exchanger with one fluid evaporating or condensing, the surface area required is least in All of these Cross flow Counter flow Parallel flow All of these Cross flow Counter flow Parallel flow ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Film coefficient is defined as Inside diameter of tube Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity Equivalent thickness of film Film coefficient × Inside diameter Thermal conductivity Thermal conductivity Equivalent thickness of film Specific heat × Viscosity Thermal conductivity Molecular diffusivity of momentum Thermal diffusivity Equivalent thickness of film Film coefficient × Inside diameter Thermal conductivity Thermal conductivity Equivalent thickness of film Specific heat × Viscosity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The product of Reynolds number and Prandtl number is known as Stanton number Peclet number Biot number Grashoff number Stanton number Peclet number Biot number Grashoff number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Wien's law, the wavelength corresponding to maximum energy is proportion to Absolute temperature (T) I² T F Absolute temperature (T) I² T F ANSWER DOWNLOAD EXAMIANS APP