For infinite parallel planes having emis-sivities $${{\varepsilon _1}}$$ & $${{\varepsilon _2}}$$, the interchange factor for radiation from surface 1 to surface 2 is given by
A. $$\frac{{{\varepsilon _1} + {\varepsilon _2}}}{{{\varepsilon _1}.{\varepsilon _2}}}$$
B. $$\frac{{{\varepsilon _1}.{\varepsilon _2}}}{{{\varepsilon _1} + {\varepsilon _2} - {\varepsilon _1}.{\varepsilon _2}}}$$
C. $${\varepsilon _1}.{\varepsilon _2}$$
D. $${\varepsilon _1} + {\varepsilon _2}$$
Answer: Option B
This Question Belongs to Chemical Engineering >> Chemical Engineering Basics
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C. Malleable iron
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B. Travelling grate stoker firing
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D. Fluidised bed
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