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Can you please help me with this question? about a refrigerator and heat?

  1. Jul 27, 2009 #1
    Can you please help me with this question?? about a refrigerator and heat?

    The problem statement, all variables and given/known data

    A) Where does the heat go which is given off by the condensation coils of the refrigerator in your kitchen?

    B) Its 90 degrees in your kitchen, you decide all windows and all doors so no heat transfer occurs between the outside and inside, then you open your refrigerator. If you leave you refrigerator open the whole day will it cool down the kitchen? Why or why not? Describe the flow of heat after the refrigerator door is opened...

    C) After 5 minutes the refrigerator door is still open.Would the air in the refrigerator be changing temperature less quickly, more quickly or at the same rate when the refrigerator door was first opened? Why is this?

    D) If the refrigerator is unplugged what happens to the flow of the heat in the room?


    Can i at least get an idea...??
     
    Last edited: Jul 27, 2009
  2. jcsd
  3. Jul 27, 2009 #2

    diazona

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    Re: Can you please help me with this question?? about a refrigerator and heat?

    Well, what are your thoughts so far? We won't just give you the answers.
     
  4. Jul 27, 2009 #3
    Re: Can you please help me with this question?? about a refrigerator and heat?

    sorry about that your completely right.....
    D) my guess is that if the refri is unplugged it loses energy which produces the heat which makes the flow of the heat in the room less rising the temperature...a guess..but i think im really off ...

    C)After 5 minutes my guess is that the temperature in the refri would have changed at the same rate...its like a close door where heat can not enter....the temperature remains the same. But if it allows heat to enter then the temperature will continue to change at a constant rate

    B) I seriously dont know about this one but im thinking that it will not cool down because its not enough energy to change the temperature to cool it down. But the flow of heat would just go out only close to the refri not enough to cover the kitchen

    A) If im right the condensation coils are on the sides of the refri...so that heat would just go outward toward the kitchen....please help me out....i just have to answer this question and i wasnt given anything to guide my self
     
  5. Jul 27, 2009 #4

    diazona

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    Re: Can you please help me with this question?? about a refrigerator and heat?

    Yep, that's right.

    OK, the kitchen won't cool down, but will it heat up or stay at the same temperature?

    Here's the way to think about it: if the windows and doors are closed and are perfect insulators, no heat can enter or leave the kitchen. So the only thing that can change the amount of heat in the kitchen is the refrigerator. Is the refrigerator generating heat, removing heat, or neither?

    True, heat can't enter through the door, but as I said, the refrigerator could be producing or consuming heat, so the temperature does not necessarily remain the same.

    umm... not sure what exactly you mean by that
     
  6. Jul 27, 2009 #5
    Re: Can you please help me with this question?? about a refrigerator and heat?

    OH wow so its producing HEAT so it will heat up the kitchen...interesting...am i right?


    the part that you didnt understand....if the refrigerator was unplugged then it loses its source of energy...electricity...so it will not be able to produce heat and it will lower the temperature of the kitchen???
     
  7. Jul 27, 2009 #6

    diazona

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    Re: Can you please help me with this question?? about a refrigerator and heat?

    Yep, that's right. But how do you know that the heat released by the coils is more than the heat absorbed by the interior of the refrigerator?

    That much is right
    Why would the temperature of the kitchen drop? If the temperature drops, it means the kitchen must be losing heat, so where would the heat be going?
     
  8. Jul 28, 2009 #7
    Re: Can you please help me with this question?? about a refrigerator and heat?

    so this is what I came up with after reviewing our conversation ....

    A...the heat is given off to the surrounding air in this case toward the kitchen

    b...no because the refrigerator will produce more heat. The fact is that if you leave the door open the whole day the refrigerator would be consuming more electricity giving more heat and emitting that heat to the kitchen. So the flow of heat would be toward the condensation coils in the back of the refrigerator

    C...it would stay at the same rate as when it was first open. The only difference is that it will produce more energy to maintain the same temperature from the beggining

    D....of the refrigerator is unplugged then it loses it's source of enrgy to produce heat so it will not be able to produce heat and the temperature stays the same.....how does that sound please correct me if I am wrong in any of them.....
     
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