How to Calculate Heat Loss Per Hour Through a Glass Window Pane?

AI Thread Summary
To calculate heat loss through a glass window pane, the relevant equation is P = k A ΔT, where P is power loss, A is the area of the window, ΔT is the temperature difference between the inner and outer surfaces, and k is a material-specific constant. The heat loss is directly proportional to both the area of the window and the temperature difference; doubling either will double the heat loss. The discussion highlights the importance of understanding the relationship between thermal conductivity and thermal resistance when determining the value of k. It is crucial to ensure the correct units are used for k to accurately calculate heat loss. The conversation emphasizes the need for clarity in applying these principles to solve the problem effectively.
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Homework Statement



A glass window pane is 2.7 m high, 2.4 m wide and 2 mm thick. The temperature at the inner surface of the glass is and at the outer surface 4°C. How much heat is lost each hour through the window?



The Attempt at a Solution



I have the stats on the glass like specific heat ect.

Im not quite sure what equations to use to solve this
 
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How would you expect the power lost to depend on the area of the window and the temperature difference?

Do you know the equation for electrical resistance of a material? How is this similar?
 
no, I am not quite sure what that equation is.
 
You can work it out simply.

You expect the heat loss to go up with more area - double the area = double the heat loss.
And you expect it be proportional to the temperature difference, double the temperature difference double the heat loss.

so you have power is proprtional to area * temperature differences
or P = k A dt
where k is some constant for your material

Depending on how your data is given 'k' might be thermal conduction = bigger number is more heat lost, or thermal resistance = small number is more heat lost, so you migth have K or 1/K in the equation. You can tell from the units given for 'k'
 
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