Heat and Mass Transfer The unit of Stefan Boltzmann constant is watt/cm4 °K watt/cm3 °K watt/cm2 °K⁴ watt2/cm °K⁴ watt/cm4 °K watt/cm3 °K watt/cm2 °K⁴ watt2/cm °K⁴ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The highest thermal diffusivity is of Wood Lead Iron Concrete Wood Lead Iron Concrete ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fourier's law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body) k. A. (dx/dT) k. (dx/dT) k. (dT/dx) k. A. (dT/dx) k. A. (dx/dT) k. (dx/dT) k. (dT/dx) k. A. (dT/dx) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A cube at high temperature is immersed in a constant temperature bath. It loses heat from its top, bottom and side surfaces with heat transfer coefficients of h₁, h₂ and h₃ respectively. The average heat transfer coefficient for the cube is 1/h₁ + 1/h₂ + 1/h₃ (h₁.h₂.h₃)1/3 h₁ + h₂ + h₃ None of these 1/h₁ + 1/h₂ + 1/h₃ (h₁.h₂.h₃)1/3 h₁ + h₂ + h₃ None of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred by molecular collision, it is referred to as heat transfer by Conduction Convection Radiation Scattering Conduction Convection Radiation Scattering ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is given by (where h = Thermal diffusivity, ρ = Density of substance, S = Specific heat, and k = Thermal conductivity) h = kρ/S h = k/ ρS h = ρS/k h = S/ρk h = kρ/S h = k/ ρS h = ρS/k h = S/ρk ANSWER DOWNLOAD EXAMIANS APP