A rigid box with insulated side walls is put in the air. Only the top wall and the bottom wall of the box are not insulated. Hot air at 70°C is blown over a 1m × 2m flat surface of the top wall of a box at 30°C. The convection heat transfer coefficient is 45 W/(m2 · °C). Determine the rate of heat transfer in kW from the bottom wall to the air, if you know that the temperature of the box remains constant and no heat is generated inside. Justify your answer.

A rigid box with insulated side walls is put in the air. Only the top wall and the bottom wall of the box are not insulated. Hot air at 70°C is blown over a 1m × 2m flat surface of the top wall of a box at 30°C. The convection heat transfer coefficient is 45 W/(m2 · °C). Determine the rate of heat transfer in kW from the bottom wall to the air, if you know that the temperature of the box remains constant and no heat is generated inside. Justify your answer.

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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