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Consider the above problem, what should be the emissivity of a polished aluminum shield placed between them if heat flow is to be reduced to 40 percent of its original value?

Consider the above problem, what should be the emissivity of a polished aluminum shield placed between them if heat flow is to be reduced to 40 percent of its original value? Correct Answer 0.347

(F g) 12 = 1/E 1 +1/E 2 +2/E 3 – 2 = 7.936.

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