Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called None of these Emissivity Absorptive power Emissive power None of these Emissivity Absorptive power Emissive power 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 Two Three Four One Two Three Four ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A grey body is one whose absorptivity Varies with temperature Does not vary with temperature and. wavelength of the incident ray Varies with wavelength of the incident ray Is equal to its emissivity Varies with temperature Does not vary with temperature and. wavelength of the incident ray Varies with wavelength of the incident ray Is equal to its emissivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A non-dimensional number generally associated with natural convection heat transfer is Grashoff number Nusselt number Prandtl number Weber number Grashoff number Nusselt number Prandtl number Weber number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In heat exchangers, degree of approach is defined as the difference between temperatures of Hot medium outlet and cold water outlet Hot medium inlet and outlet Hot medium outlet and cold water inlet Cold water inlet and outlet Hot medium outlet and cold water outlet Hot medium inlet and outlet Hot medium outlet and cold water inlet Cold water inlet and outlet ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in S.I. units is W/m °K J/m² sec J/m °K sec Option (B) and (C) above W/m °K J/m² sec J/m °K sec Option (B) and (C) above ANSWER DOWNLOAD EXAMIANS APP
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