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Fridge Question

  1. Nov 4, 2005 #1
    A colleague has just posed this question and I need some help.

    There is a sealed room in space that has no external infulences.

    Inside the room is a fridge. The fridge is powered on and its door is open.

    The question is, what happens to the temperature of the room ???
  2. jcsd
  3. Nov 4, 2005 #2


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    Seems very much like a homework problem.

    What do you think will happen?
  4. Nov 4, 2005 #3
    Because the conservation of the energy.
    If you use the energy of the electricity, then the energy must convert into other forms.
  5. Nov 4, 2005 #4
    Not homework - just something to talk about at work.

    I think the obvious answer is that the temperature will rise - power is being put into a sealed system - therefore the effect is that the energy being put in will cause heat to be generated.

    But I am curious about whether the cooling aspect of the fridge would have any effect.
  6. Nov 4, 2005 #5
    I think.........
    ..while the fridge is running, the temperature in front of the door is really falling (your cooling effect) and the temperature behind the fridge is rising, but more than it is falling in front of the door.......

    after some time the fridge will consume all the energy added............and temperature will balance.....and of course the result is higher temperature (due to 2nd Thermodynamic law).
  7. Nov 4, 2005 #6
    What happens next then if the fridge is constantly running, surely the temperature just keeps rising - more energy in = more heat ???
  8. Nov 4, 2005 #7
    yes. exactly.
    and the time the fridge is running depends on amount of energy for the fridge in the system at the beggining. (sealed system).
  9. Nov 4, 2005 #8
    Cool, thanks for your help.
  10. Nov 4, 2005 #9


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    Was that a pun?


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