Heat and Mass Transfer When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a Grey body Opaque body White body Black body Grey body Opaque body White body Black body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The process of heat transfer from one particle of the fluid to another by the actual movement of the fluid particles caused by some mechanical means, is known as Free convection Forced convection Radiation Conduction Free convection Forced convection Radiation Conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Cork is a good insulator because it has Free electrons Porous body Low density Atoms colliding frequency Free electrons Porous body Low density Atoms colliding frequency ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Total emissivity of polished silver compared to black body is Same Very much lower Higher More or less same Same Very much lower Higher More or less same ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 20°C 66.7°C 40°C 60°C 20°C 66.7°C 40°C 60°C 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 = S/ρk h = ρS/k h = k/ ρS h = kρ/S h = S/ρk h = ρS/k h = k/ ρS ANSWER DOWNLOAD EXAMIANS APP