Calculate the rate of steady heat transfer from a 8 m-by-10 m roof of a building during a cold winter day. The roof temperature can be assumed to be constant at 12°C. The air temperature outside the building is -5°C. The sky temperature is -17°C. The solar irradiation at the location is 500 W/m². The convection coefficient can be assumed to be 8 W/m².°c. The emissivity of the roof is 0.75, and solar absorptivity is 0.4. Neglect any conduction via the walls to the ground. 2173 W

Calculate the rate of steady heat transfer from a 8 m-by-10 m roof of a building during a cold winter day. The roof temperature can be assumed to be constant at 12°C. The air temperature outside the building is -5°C. The sky temperature is -17°C. The solar irradiation at the location is 500 W/m². The convection coefficient can be assumed to be 8 W/m².°c. The emissivity of the roof is 0.75, and solar absorptivity is 0.4. Neglect any conduction via the walls to the ground. 2173 W

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 117AP: (a) Calculate the rate of heat conduction through a double-paned window that has a 150-m2 area and...

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