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

  1. 992
  2. 812
  3. 464
  4. 567

Answer (Detailed Solution Below)

Option 2 : 812
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ϵ = 0.9, T1 = 400 K, T2 = 300 K

σ = 5.67 × 10-8 W/m2K4

Heat transfer per unit area between parallel grey surfaces is given by

 

 

Q = 811.84 W/m2

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