12.37 Consider the metallic surface of Example 12.7. Addi- tional measurements of the spectral, hemispherical emissivity yield a spectral distribution which may be approximated as follows: 0.4 * 0.2 2 4 a (um) (a) Determine corresponding values of the total, hemi- spherical emissivity ɛ and the total emissive power E at 2000 K. Ez (2.)

12.37 Consider the metallic surface of Example 12.7. Addi- tional measurements of the spectral, hemispherical emissivity yield a spectral distribution which may be approximated as follows: 0.4 * 0.2 2 4 a (um) (a) Determine corresponding values of the total, hemi- spherical emissivity ɛ and the total emissive power E at 2000 K. Ez (2.)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Liquid oxygen is stored in a thin-walled, spherical container 0.8 m in diameter, which is enclosed within a second thin-walled, spherical container 1.2 m in diameter. The opaque, diffuse, gray container surfaces have an emissivity of 0.05 and are separated by an evacuated space. If the outer surface is at 270 K and the inner surface is at 95 K, what is the mass rate of oxygen lost due to evaporation, in kg/s? (The latent heat of vaporization of oxygen is 2.13 x 105 J/kg.) i kg/s
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Calculate the absorbed irradiation by the surface in W/m2
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please show all steps, not Ai generated
Liquid oxygen is stored in a thin-walled, spherical container 0.8 m in diameter, which is enclosed within a second thin-walled, spherical container 1.2 m in diameter. The opaque, diffuse, gray container surfaces have an emissivity of 0.05 and are separated by an evacuated space. If the outer surface is at 270 K and the inner surface is at 95 K, what is the mass rate of oxygen lost due to evaporation, in kg/s? (The latent heat of vaporization of oxygen is 2.13 x 105 J/kg.) m = kg/s Physical Properties Mathematical Functions
An opaque surface has the spectral, hemispherical reflectivity distribution as shown below. The surface receives the spectral irradiation shown below. A. Determine the total irradiation on the surfaceB. Determine the radiant flux that is absorbed by the surface