Heat and Mass Transfer Thermal conductivity of water _________ with rise in temperature. Increases May increase or decrease depending upon temperature Remain same Decreases Increases May increase or decrease depending upon temperature Remain same Decreases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity) RN = hl/k RN = V²/t.cp RN = ρ V l /μ RN = μ cp/k RN = hl/k RN = V²/t.cp RN = ρ V l /μ RN = μ cp/k ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A non-dimensional number generally associated with natural convection heat transfer is Prandtl number Weber number Grashoff number Nusselt number Prandtl number Weber number Grashoff number Nusselt number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following property of air does not increase with rise in temperature? Density Dynamic viscosity Thermal conductivity Thermal diffusivity Density Dynamic viscosity Thermal conductivity Thermal diffusivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is All of these Directly proportional to the thermal conductivity Inversely proportional to specific heat Inversely proportional to density of substance All of these Directly proportional to the thermal conductivity Inversely proportional to specific heat Inversely proportional to density of substance ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP