Stainless steel ball bearings (p=8085 kg/m², k=15.1 W/m°C, and C=0.480 kJ/kg.°C) having diameter of 1.2 cm are to be quenched in water. The ball leaving the oven at a uniform temperature of 900°C and is exposed to air at 30°C and with a convection coefficient of 125W/m².°C. Determine the time necessary to reach its surface to 850°C.

Stainless steel ball bearings (p=8085 kg/m², k=15.1 W/m°C, and C=0.480 kJ/kg.°C) having diameter of 1.2 cm are to be quenched in water. The ball leaving the oven at a uniform temperature of 900°C and is exposed to air at 30°C and with a convection coefficient of 125W/m².°C. Determine the time necessary to reach its surface to 850°C.

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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