The emissivity of a surface coated with aluminum oxide can be approximated to be 0 15 for radiation at wavelengths less than 5 m and 0 9 for radiation at wavelengths greater than 5 m Determine the average emissivity of this surface at (a) 5800 K (b) 300 K What can you say about the absorptivity of ...

The variation of emissivity of a surface with wavelength is given The average emissivit ...

The emissivity of a surface coated with aluminum oxide can be approximated to be 0.15 for radiation

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The emissivity of a surface coated with aluminum oxide can be approximated to be 0.15 for radiation at wavelengths less than 5 μm and 0.9 for radiation at wavelengths greater than 5 μm. Determine the average emissivity of this surface at

(a) 5800 K

(b) 300 K. What can you say about the absorptivity of this surface for radiation coming from sources at 5800 K and 300 K?

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Fundamentals of Thermal-Fluid Sciences

ISBN: 978-0078027680

5th edition

Authors: Yunus A. Cengel, Robert H. Turner, John M. Cimbala

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Question Posted: Dec 10, 2018 04:12 AM

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