Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) 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 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer An ordinary passenger aircraft requires a cooling system of capacity. 4 TR 8 TR 2 TR 10 TR 4 TR 8 TR 2 TR 10 TR ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The use of heat exchangers is made in Condensers and evaporators in refrigeration and air conditioning units All of these Condensers and boilers in steam plants Radiators in automobile Condensers and evaporators in refrigeration and air conditioning units All of these Condensers and boilers in steam plants Radiators in automobile ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by Convection Radiation Free convection Forced convection Convection Radiation Free convection Forced convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The thermal diffusivities for solids are generally Less than those for liquids Less than those for gases More than those for liquids and gases More or less same as for liquids and gases Less than those for liquids Less than those for gases More than those for liquids and gases More or less same as for liquids and gases 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 = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP