Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
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Chapter 11, Problem 11.3P

Determine the total average hemispherical emissivity and the emissive power of a surface that has a spectral hemispherical emissivity of 0.8 at wavelengths less than 1.5   μ m , 0.6 at wavelengths from 1.5  to  2.5   μ m , and 0.4 at wavelengths longer than 2.5   μ m . The surface temperature is 1111 K.

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Principles of Heat Transfer (Activate Learning wi...
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