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Consider radiant heat exchange between two non-black parallel surfaces. The surface 1 emits radiant energy E 1 which strikes the surface 2. Identify the correct option

Consider radiant heat exchange between two non-black parallel surfaces. The surface 1 emits radiant energy E 1 which strikes the surface 2. Identify the correct option Correct Answer The value of D is (1 – α1) (1 – α2) 2 E 1

The surface 1 emits radiant energy E 1 which strikes the surface 2. From it a part α2 E 1 is absorbed by the surface 2 and the remainder (1 – α2) E 1 is reflected back to surface 1 and so on.

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