An 8-m long square duct with thin metal walls is hanging in a room where the temperature is 10 °C. Air enters the duct at 75 °C. The air has a specific heat of 1000 J/kg K and is flowing at 0.015 kg/s. The internal convection coefficient is 25 W/m2 K, and the external convection coefficient is 15 W/m2 K. The perimeter length of the duct is 18 cm. Neglecting radiation, what is the temperature of the air at the duct exit? (a) 10.2°C (b) 16.2'C (c) 25.0°C (d) 36.4°C (e) 42.5°C (f) 61.1'C (g) 74.8°C

An 8-m long square duct with thin metal walls is hanging in a room where the temperature is 10 °C. Air enters the duct at 75 °C. The air has a specific heat of 1000 J/kg K and is flowing at 0.015 kg/s. The internal convection coefficient is 25 W/m2 K, and the external convection coefficient is 15 W/m2 K. The perimeter length of the duct is 18 cm. Neglecting radiation, what is the temperature of the air at the duct exit? (a) 10.2°C (b) 16.2'C (c) 25.0°C (d) 36.4°C (e) 42.5°C (f) 61.1'C (g) 74.8°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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