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Newton's Law of Cooling

  1. Feb 22, 2015 #1
    If the temperature of an object with temperature T(t) is place in a room with the ambient temperature Ta, Newtons Law of Cooling is defined as dT / dt = k (T(t) - Ta), correct?

    This implies we would need a negative k-value. Wouldn't the equation therefore be described better if T(t) and Ta changed place? As in: dT / dt = k (Ta - T(t))

    What am I missing?
  2. jcsd
  3. Feb 22, 2015 #2


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    Staff: Mentor

    The convention is somewhat arbitrary, but I think it makes sense for heat loss to be negative and heat gain to be positive.
  4. Feb 23, 2015 #3
    The firm of the equation I am familiar with is the one that you suggested.

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