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Painting half a house black in Quebec

  1. Jan 27, 2007 #1
    1. The problem statement, all variables and given/known data
    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.

    2. Relevant equations

    3. 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.
  2. jcsd
  3. Jan 27, 2007 #2

    Chi Meson

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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.
  4. Jan 27, 2007 #3
    I changed my mind.

    Since Queec is way north of the equator, the southern half of the house should be painted black. It will recieve 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.
  5. Jan 27, 2007 #4

    Chi Meson

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    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.
  6. Jan 27, 2007 #5


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    Remember to buy your paint in a French owned store, though, if you wish to appear non-discriminatory. :smile:
  7. Jan 27, 2007 #6
    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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