Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Emissivity of a white polished body in comparison to a black body is Higher Same Depends upon the shape of body Lower Higher Same Depends upon the shape of body Lower ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical thickness of insulation for a sphere is 2k/h₀ k/h₀ h₀/k h₀/2k 2k/h₀ k/h₀ h₀/k h₀/2k 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 outlet and cold water inlet Cold water inlet and outlet Hot medium inlet and outlet Hot medium outlet and cold water outlet Hot medium outlet and cold water inlet Cold water inlet and outlet Hot medium inlet and outlet ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A cube at high temperature is immersed in a constant temperature bath. It loses heat from its top, bottom and side surfaces with heat transfer coefficients of h₁, h₂ and h₃ respectively. The average heat transfer coefficient for the cube is h₁ + h₂ + h₃ None of these (h₁.h₂.h₃)1/3 1/h₁ + 1/h₂ + 1/h₃ h₁ + h₂ + h₃ None of these (h₁.h₂.h₃)1/3 1/h₁ + 1/h₂ + 1/h₃ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in S.I. units is J/m °K sec Option (B) and (C) above W/m °K J/m² sec J/m °K sec Option (B) and (C) above W/m °K J/m² sec ANSWER DOWNLOAD EXAMIANS APP