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Temperature of Water in a Moving Plane

  1. Sep 13, 2010 #1
    Hello people,

    i have been wondering if translational K.E = 3/2 RT, where T is the temperature, why is it that when we place a cup of water in a fast moving jet, the Temperature still remains the same, even though the K.E of the cup of water increases (due to the velocity of the jet)

    would appreciate if someone help clear some doubts,
    thanks in advance!
  2. jcsd
  3. Sep 13, 2010 #2


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    Gold Member

    I assume it's because the cup, and the surrounding air, are stationary relative to the vehicle.
  4. Sep 13, 2010 #3
    is it possible to explain this in terms of internal energy?
  5. Sep 13, 2010 #4
    The internal K.E. of the cup is T3/2 R relative to its own center of mass.

    Relative to the airport, Total K.E. = (3/2)TR + (1/2)mv^2. (v being the speed of the center of mass).
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