The emissivity of a tungsten filament can be approximated to be 0 5 for radiation at wavelengths less than 1 m and 0 15 for radiation at greater than 1 m Determine the average emissivity of the filament at (a) 2000 K (b) 3000 K Also, determine the absorptivity and reflectivity of the filament at bo...

The variation of emissivity of a tungsten filament with wavelength is given Th ...

The emissivity of a tungsten filament can be approximated to be 0.5 for radiation at wavelengths less

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The emissivity of a tungsten filament can be approximated to be 0.5 for radiation at wavelengths less than 1 μm and 0.15 for radiation at greater than 1 μm. Determine the average emissivity of the filament at

(a) 2000 K

(b) 3000 K. Also, determine the absorptivity and reflectivity of the filament at both temperatures.

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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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