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Two large parallel black plates are maintained at 27 C and 127 C. Taking Stefan's constant as (17/3) x 10⁻⁸ W/m²-K⁴, find the net rate of radiative heat transfer per unit area between the plates.

1. 992 W/m²
2. 14.71 W/m²
3. 446 W/m²
4. 29.5 W/m²

Correct answer: 992 W/m²

Solution

Using net flux = sigma*(T2⁴ - T1⁴) with T = 400 K and 300 K gives about 992 W/m².

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