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Homework Help: Freezer question

  1. Apr 5, 2005 #1
    I have this question to do, any I can't work it out! I've looked everywhere, all through my textbook and all over the internet, and I just can't find it. It is...

    Explain what leaving the freezer door open would do to the temperature of the room the freezer is in.

    I'm not completely sure, would it cool the room, but only slightly, because the freezer is only designed to cool a small space?
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  3. Apr 5, 2005 #2

    Andrew Mason

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    A refridgerator moves heat from the inside of the box to the outside of the box. In order to do this it does some work which is also released as heat. The heat that is taken out of the box plus the energy (work) added is delivered as heat to the room (feel the coils at the back of your fridge/freezer).

    So if it takes heat from inside and puts it and a little more outside, and that outside heat moves around and goes inside again, does the total heat in the room go up, down or stay the same?

  4. Apr 5, 2005 #3


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    Don't know if this is too nitpicky to be considered, but note that the room is not a closed system. Energy is entering (or has previously entered) the room in the form of electricity.

    Yeah, it's proably too nitpicky. Go with Andrew's answer.
  5. Apr 5, 2005 #4
    Thanks guys, that really helped, I think I understand it now.
  6. Apr 6, 2005 #5


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    In the long run, as others noticed, it would heat up the room. But when the freezer is cold, with a closed door, and you then open the door, in the beginning, the temperature of the room will DROP slightly, because heat from the room is extracted to heat up the cold part of the freezer. It is only later, when the motor of the freezer is pumping and pumping, that you will slowly start to heat the room (indeed, as said here before, the room is consuming a certain amount of electricity: that's the energy going IN the room ; nothing is supposed to come out, so the internal energy must rise).

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