16. A 12 cm diameter long bar initially at a uniform temperature of 40°C is placed in a medium at 650°C with a convective co efficient of 22 W/m*K calculate the time required for the bar to reach255°C. Take k = 20W/mK, p = 580 kg/m' and e = 1050 J/kg K. Given : Unsteady state D- 12 cm = 0.12 m R=0.06 m T.- 40 + 273 = 313 K T.- 650 + 273 = 923 K T- 255 + 273 -528s K h- 22 W/m°K k= 20 W/mK p= 580 Kg'm' c = 1050 J/kg K Find: Time required to reach 255°C ()

16. A 12 cm diameter long bar initially at a uniform temperature of 40°C is placed in a medium at 650°C with a convective co efficient of 22 W/m*K calculate the time required for the bar to reach255°C. Take k = 20W/mK, p = 580 kg/m' and e = 1050 J/kg K. Given : Unsteady state D- 12 cm = 0.12 m R=0.06 m T.- 40 + 273 = 313 K T.- 650 + 273 = 923 K T- 255 + 273 -528s K h- 22 W/m°K k= 20 W/mK p= 580 Kg'm' c = 1050 J/kg K Find: Time required to reach 255°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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