Heat and Mass Transfer The value of the wave length for maximum emissive power is given by Stefan’s law Planck’s law Wine’s law Kirchhoff’s law Stefan’s law Planck’s law Wine’s law Kirchhoff’s law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat of sun reaches to us according to None of these Radiation Convection Conduction None of these Radiation Convection Conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical thickness of insulation for a sphere is 2k/h₀ h₀/2k k/h₀ h₀/k 2k/h₀ h₀/2k k/h₀ h₀/k ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The product of Reynolds number and Prandtl number is known as Biot number Grashoff number Stanton number Peclet number Biot number Grashoff number Stanton number Peclet number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following would lead to a reduction in thermal resistance? In radiation, increasing the temperature and reducing the emissivity. In conduction, reduction in the thickness of the material and an increase in thermal conductivity. All of these In convection, stirring of the fluid and cleaning the heating surface. In radiation, increasing the temperature and reducing the emissivity. In conduction, reduction in the thickness of the material and an increase in thermal conductivity. All of these In convection, stirring of the fluid and cleaning the heating surface. ANSWER DOWNLOAD EXAMIANS APP