A bearing piece in the form of half of a hollow cylinder of 60 mm ID, 90 mm OD and 100 mm long is to be cooled to -100°C from 30°C using a cryogenic gas at –150°C with a convection coefficient of 70W/m²K. density = 8900 kg/m', specific heat 444 J/kgK, conductivity = 17.2 W/mK. Determine the time required. (1)

A bearing piece in the form of half of a hollow cylinder of 60 mm ID, 90 mm OD and 100 mm long is to be cooled to -100°C from 30°C using a cryogenic gas at –150°C with a convection coefficient of 70W/m²K. density = 8900 kg/m', specific heat 444 J/kgK, conductivity = 17.2 W/mK. Determine the time required. (1)

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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