Heat and Mass Transfer Fourier's law of heat conduction is valid for One dimensional cases only Two dimensional cases only Three dimensional cases only Regular surfaces having non-uniform temperature gradients One dimensional cases only Two dimensional cases only Three dimensional cases only Regular surfaces having non-uniform temperature gradients ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Metals are good conductors of heat because They have high density Their atoms are relatively far apart Their atoms collide frequently They contain free electrons They have high density Their atoms are relatively far apart Their atoms collide frequently They contain free electrons 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 Two One Four Three Two One Four Three ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of air with rise in temperature Decreases Increases May increase or decrease depending on temperature Remain constant Decreases Increases May increase or decrease depending on temperature Remain constant ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when(Where a = absorptivity, p = reflectivity, x = transmissivity) P=1, x = 0, and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P = 0, x= 1, and a = 0 P=1, x = 0, and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P = 0, x= 1, and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be 800 mm 40 mm 160 mm 25 mm 800 mm 40 mm 160 mm 25 mm ANSWER DOWNLOAD EXAMIANS APP