A wood log (k = 0.17 W/m · K and a = 1.28 × 10-7 m²/s) is 7.5 cm in diameter and is initially at a uniform temperature of 15°C. It is exposed to hot gases at 500°C in a fireplace with a heat transfer coefficient of 13.6 W/m2 · K on the surface. If the ignition temperature of the wood is 420°C, determine how long it will be before the log ignites.

A wood log (k = 0.17 W/m · K and a = 1.28 × 10-7 m²/s) is 7.5 cm in diameter and is initially at a uniform temperature of 15°C. It is exposed to hot gases at 500°C in a fireplace with a heat transfer coefficient of 13.6 W/m2 · K on the surface. If the ignition temperature of the wood is 420°C, determine how long it will be before the log ignites.

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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