Steel balls (diameter = 21 mm, p = 7833 kg/m , k = 54 W/M•°C, Cp =p.45 kJ/kg-°C, and a = 1.474x10 m /s) are annealed by heating them first to 870°C in a furnace and then allowing them to cool slowly to 85°C in ambient air at 27°C. The average heat transfer coefficient is 41 W/m ·°C. How long the annealing process will take (in Seconds)? %3D %3D

Steel balls (diameter = 21 mm, p = 7833 kg/m , k = 54 W/M•°C, Cp =p.45 kJ/kg-°C, and a = 1.474x10 m /s) are annealed by heating them first to 870°C in a furnace and then allowing them to cool slowly to 85°C in ambient air at 27°C. The average heat transfer coefficient is 41 W/m ·°C. How long the annealing process will take (in Seconds)? %3D %3D

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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Heat Transfer
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