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Homework Help: Homework Help: Gen Physics

  1. Jun 23, 2007 #1
    HW Help: Absolute temp and ideal gas law

    1. The problem statement, all variables and given/known data
    What fraction of the air molecules in a house must be pushed outside while the furnace raises the inside temperature from 16C to 20C? The pressure does not change since the house is not 100% airtight.

    2. Relevant equations

    3. The attempt at a solution
    NkT=NkT? N2/N1 = T2/T1. N2 = .80N1. Answer provided is .0136. I can't figure how that answer comes about. Help would be grateful. Thanks.
    Last edited: Jun 23, 2007
  2. jcsd
  3. Jun 23, 2007 #2


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    Science Advisor
    Homework Helper

    You need to take the temperature ratio in degrees Kelvin i.e. T=0 should be absolute zero.
  4. Jun 23, 2007 #3


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    Gold Member

    Assuming the pressure inside the house does not change, your formula is correct. It's OK to solve in degrees C, the answer is relational.
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