Heat and Mass Transfer Unit of thermal conductivity in S.I. units is J/m °K sec W/m °K J/m² sec Option (B) and (C) above J/m °K sec W/m °K J/m² sec Option (B) and (C) above 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 Four One Three Two Four One Three Two ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The unit of Stefan Boltzmann constant is watt2/cm °K⁴ watt/cm2 °K⁴ watt/cm3 °K watt/cm4 °K watt2/cm °K⁴ watt/cm2 °K⁴ watt/cm3 °K watt/cm4 °K ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Sensible heat factor is given by (where S.H. = Sensible heat, and L.H. = Latent heat) (S.H + L.H) /S.H S.H/(L.H - S.H) (L.H - S.H)/S.H S.H/(S.H + L.H) (S.H + L.H) /S.H S.H/(L.H - S.H) (L.H - S.H)/S.H S.H/(S.H + L.H) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thermal diffusivities for solids are generally Less than those for gases More or less same as for liquids and gases More than those for liquids and gases Less than those for liquids Less than those for gases More or less same as for liquids and gases More than those for liquids and gases Less than those for liquids 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 = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP