The concrete wall of a building is 0.18 m thick. The temperature inside the building is 22.8°C, while the temperature outside is 0.0°C. Heat is conducted through the wall. When the building is unheated, the inside temperature falls to 0.0°C, and heat conduction ceases. However, the wall does emit radiant energy when its temperature is 0.0°C. The radiant energy emitted per second per square meter is the same as the heat lost per second per square meter due to conduction. What is the emissivity of the wall?(adsbygoogle = window.adsbygoogle || []).push({});

This is the problem I have to solve. I was thinking that I might need to use a combination of equations to solve this such as: H=kA(delta)T/L or Q=e(stefan-bolzmann constant)At(T^4).

But I don't even know where to start. Please help me!!!

thank you

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# Homework Help: Need help with transfer of heat/radiation/emissivity problem

Can you offer guidance or do you also need help?

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