The radiative heat transfer rate per unit area (W/m2) between two plane parallel gray surfaces (emissivity = 0.9) maintained at 400 K and 300 K is ( = Stefan Boltzmann constant = 5.67 10 8 W/m2K4)

The radiative heat transfer rate per unit area (W/m2) between two plan

1.	The radiative heat transfer rate per unit area (W/m2) between two plane parallel gray surfaces (emissivity = 0.9) maintained at 400 K and 300 K is ( = Stefan Boltzmann constant = 5.67 10 8 W/m2K4)
A.	992
B.	812
C.	464
D.	567
Answer» C. 464

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The radiative heat transfer rate per unit area (W/m2) between two plane parallel gray surfaces (emissivity = 0.9) maintained at 400 K and 300 K is ( = Stefan Boltzmann constant = 5.67 10 8 W/m2K4)

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