Heat and Mass Transfer In counter flow heat exchangers Both the fluids at inlet are in their hottest state One fluid is in hottest state and other in coldest state at inlet Both the fluids at exit are in their hottest state Both the fluids at inlet (of heat exchanger where hot fluid enters) are in their coldest state Both the fluids at inlet are in their hottest state One fluid is in hottest state and other in coldest state at inlet Both the fluids at exit are in their hottest state Both the fluids at inlet (of heat exchanger where hot fluid enters) are in their coldest state 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 = ρ V l /μ RN = V²/t.cp RN = μ cp/k RN = hl/k RN = ρ V l /μ RN = V²/t.cp RN = μ cp/k RN = hl/k ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is All of these Inversely proportional to density of substance Inversely proportional to specific heat Directly proportional to the thermal conductivity All of these Inversely proportional to density of substance Inversely proportional to specific heat Directly proportional to the thermal conductivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following property of air does not increase with rise in temperature? Dynamic viscosity Thermal diffusivity Thermal conductivity Density Dynamic viscosity Thermal diffusivity Thermal conductivity Density ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is Equal to one Equal to Nusselt number Greater than one Less than one Equal to one Equal to Nusselt number Greater than one Less than one ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Upto the critical radius of insulation, Added insulation will decrease heat loss Convective heat loss will be less than conductive heat loss Heat flux will decrease Added insulation will increase heat loss Added insulation will decrease heat loss Convective heat loss will be less than conductive heat loss Heat flux will decrease Added insulation will increase heat loss ANSWER DOWNLOAD EXAMIANS APP
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