Heat and Mass Transfer Depending on the radiating properties, a body will be white when (Where a = absorptivity, p = reflectivity, x = transmissivity) X = 0, a + p = 1 P=1, T = 0 and a = 0 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 X = 0, a + p = 1 P=1, T = 0 and a = 0 P = 0, x = 0 and a = 1 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The emissivity for a black body is 0.75 0.5 1 0.75 0.5 1 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is Less than one Equal to Nusselt number Greater than one Equal to one Less than one Equal to Nusselt number Greater than one Equal to one ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities. For the minimum heat transfer, One should take into account the steam temperature before deciding as to which insulation is put where The better insulation must be put outside One could place either insulation on either side The better insulation must be put inside One should take into account the steam temperature before deciding as to which insulation is put where The better insulation must be put outside One could place either insulation on either side The better insulation must be put inside 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 None of these (h₁.h₂.h₃)1/3 1/h₁ + 1/h₂ + 1/h₃ h₁ + h₂ + h₃ None of these (h₁.h₂.h₃)1/3 1/h₁ + 1/h₂ + 1/h₃ h₁ + h₂ + h₃ 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. (dT/dx) k. A. (dT/dx) k. (dx/dT) k. A. (dx/dT) k. (dT/dx) k. A. (dT/dx) k. (dx/dT) ANSWER DOWNLOAD EXAMIANS APP