Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 270 3 81 9 270 3 81 9 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is Greater than one Equal to one Less than one Equal to Nusselt number Greater than one Equal to one Less than one Equal to Nusselt number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The transfer of heat by molecular collision is smallest in Solids None of these Gases Liquids Solids None of these Gases Liquids ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The time constant of a thermocouple is The time taken to attain the final temperature to be measured The time taken to attain 50% of the value of initial temperature difference Determined by the time taken to reach 100°C from 0°C The time taken to attain 63.2% of the value of initial temperature difference The time taken to attain the final temperature to be measured The time taken to attain 50% of the value of initial temperature difference Determined by the time taken to reach 100°C from 0°C The time taken to attain 63.2% of the value of initial temperature difference ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The expression Q = ρ AT4 is called Joseph-Stefan equation Fourier equation Newton Reichmann equation Stefan-Boltzmann equation Joseph-Stefan equation Fourier equation Newton Reichmann equation Stefan-Boltzmann equation ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be One Four Three Two One Four Three Two ANSWER DOWNLOAD EXAMIANS APP
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