Heat and Mass Transfer Depending on the radiating properties, body will be transparent when (Where a = absorptivity, p = reflectivity, x = transmissivity) X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P=1, x = 0, and a = 0 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The rate of energy transferred by convection to that by conduction is called Peclet number Stanton number Biot number Nusselt number Peclet number Stanton number Biot number Nusselt number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by 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) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The radiation emitted by a black body is known as Black radiation Full radiation Total radiation All of these Black radiation Full radiation Total radiation All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The insulation ability of an insulator with the presence of moisture would Decrease Remain unaffected Increase May increase/decrease depending on temperature and thickness of insulation Decrease Remain unaffected Increase May increase/decrease depending on temperature and thickness of insulation 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 Three Four Two One Three Four Two ANSWER DOWNLOAD EXAMIANS APP
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