Heat and Mass Transfer A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be k₁ k₂ (k₁ + k₂) (k₁ + k₂)/ k₁ k₂ 2 k₁ k₂/ (k₁ + k₂) k₁ k₂ (k₁ + k₂) (k₁ + k₂)/ k₁ k₂ 2 k₁ k₂/ (k₁ + k₂) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The insulation ability of an insulator with the presence of moisture would May increase/decrease depending on temperature and thickness of insulation Increase Remain unaffected Decrease May increase/decrease depending on temperature and thickness of insulation Increase Remain unaffected Decrease ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer 40% of incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is 0.55 0.45 0.4 0.75 0.55 0.45 0.4 0.75 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat is transferred by conduction, convection and radiation in Boiler furnaces None of these Melting of ice Condensation of steam in condenser Boiler furnaces None of these Melting of ice Condensation of steam in condenser ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS