Painting half a house black in Quebec

  • Thread starter Thread starter WolfishGrin
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AI Thread Summary
To minimize heating costs for Alice's house in Quebec, the southern half should be painted black to maximize sun exposure throughout the day, while the northern half should be painted white to reflect minimal sunlight. The discussion highlights the importance of considering thermodynamics, particularly the absorptive and radiative qualities of black and white paint. The initial thought of splitting the house east-west was reconsidered in favor of a north-south split due to Quebec's northern latitude. The conversation also touches on the cultural aspect of purchasing paint from a French-owned store. Ultimately, the decision is based on maximizing heat absorption in the southern half while minimizing heat gain in the northern half.
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Homework Statement


Alice lives in the Quebec. She wishes to build a new home and paint one-half of the outside black and the other half white. She can either split the house east-west or north-south. State which half she should paint white and which half she should paint black in order to minimize heating costs and explain this decision based on thermodynamics.


Homework Equations


N/A


The Attempt at a Solution


Right now, I'm basically lost as to where to start. I know the sun rises in the east and settles in the west, so I am guessing I'm going to split the house east-west. Now, which side is better? I think Quebec would be colder when the sun is rising than when the sun is setting, so my best bet is that I should paint the east black to bring more radiation heat into the house.
 
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First of all, consider whether overall heating, or overall cooling is more important in Quebec.

Then consider not only the absorptive qualities of black vs white, but the radiative qualities as well.
 
I changed my mind.

Since Queec is way north of the equator, the southern half of the house should be painted black. It will receive maximum sun exposure all day as opposed to only half the day (east/west), whereas the northern half should be painted white because it will reciev eminimal sun exposure.
 
WolfishGrin said:
I changed my mind.

Since Queec is way north of the equator, the southern half of the house should be painted black. It will receive maximum sun exposure all day as opposed to only half the day (east/west), whereas the northern half should be painted white because it will reciev eminimal sun exposure.

That's what I would do. Furthermore, why bother painting the north side white? Why not paint it black? There is a reason, and I alluded to it in my previous post.
 
Remember to buy your paint in a French owned store, though, if you wish to appear non-discriminatory. :smile:
 
arildno said:
Remember to buy your paint in a French owned store, though, if you wish to appear non-discriminatory. :smile:
Haha. :biggrin:

Thanks for the help, Chi. :) I'm only allowed to paint one half black, and one half has to be white. It's a strange question. I appreciate the second opinion. :)
 
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