Two large diffuse Gray parallel plates, separated by a small distance, have surface temperature of 400 K and 300 K. If the emissivities of the surfaces are 0.8 and the Stefan-Boltzmann constant is 5.67 10-8W/m2K4, the net radiation heat exchange rate in kW/m2 between the two plates is

Two large diffuse Gray parallel plates, separated by a small distance,

1.	Two large diffuse Gray parallel plates, separated by a small distance, have surface temperature of 400 K and 300 K. If the emissivities of the surfaces are 0.8 and the Stefan-Boltzmann constant is 5.67 10-8W/m2K4, the net radiation heat exchange rate in kW/m2 between the two plates is
A.	0.66
B.	0.79
C.	0.99
D.	3.96
Answer» B. 0.79

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Two large diffuse Gray parallel plates, separated by a small distance, have surface temperature of 400 K and 300 K. If the emissivities of the surfaces are 0.8 and the Stefan-Boltzmann constant is 5.67 10-8W/m2K4, the net radiation heat exchange rate in kW/m2 between the two plates is

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