5.6 Steel balls 12 mm in diameter are annealed by heating to 1150 K and then slowly cooling to 400 K in an air envi- ronment for which T325 K and h = 20 W/m².K. Assuming the properties of the steel to be k = 40 W/m.K, p= 7800 kg/m³, and c=600 J/kg K, estimate the time` required for the cooling process.

5.6 Steel balls 12 mm in diameter are annealed by heating to 1150 K and then slowly cooling to 400 K in an air envi- ronment for which T325 K and h = 20 W/m².K. Assuming the properties of the steel to be k = 40 W/m.K, p= 7800 kg/m³, and c=600 J/kg K, estimate the time` required for the cooling process.

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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REFERENCE: FROM BOOK - ENGINEERING THERMOFLUIDS, M. MASSOUD
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