Question
Download Solution PDFA 1m diameter spherical cavity is maintained at a uniform temperature of 500 K. The emissivity of the material of the sphere is 0.5; One 10 mm diameter hole is drilled. The maximum rate of radiant energy streaming through the hole will be
This question was previously asked in
ESE Mechanical 2014 Official Paper - 1
Answer (Detailed Solution Below)
Option 2 : 0.139 W
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ST 1: UPSC ESE (IES) Civil - Building Materials
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20 Questions
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Detailed Solution
Download Solution PDFConcept:
Qradiation = σϵAT4
Calculation:
Given T = 500 k, d = 10 mm, ϵ = 0.5;
\({Q_r} = 5.678 \times {10^{ - 8}} \times 0.5 \times \frac{\pi }{4}{\left( {0.01} \right)^2} \times {\left( {500} \right)^4}\)
∴ Qr = 0.139 W
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