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If I had two cups of hot water and put one in the fridge and left one

  1. Dec 21, 2009 #1
    If I had two cups of hot water and put one in the fridge and left one on the table which one after 10 minutes would be cooler ?
    I have no idea and have been asked this question, thanks in advance for the answer.
     
  2. jcsd
  3. Dec 21, 2009 #2

    mgb_phys

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    Re: Heat

    All else being equal the rate of cooling depend son the temperature difference between the water and it's surroundings - so unless it's very cold in your kitchen, the fridge would be better.
     
  4. Dec 21, 2009 #3

    ideasrule

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    Re: Heat

    Do you really need physics to answer this question? I mean, really? I don't want to be harsh, but common sense should tell you the answer.
     
  5. Dec 21, 2009 #4

    mgb_phys

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    Re: Heat

    Isn't physics simply asking 'why' to commonsense questions?

    edit: I did think they would follow up with a more 'but why' type question !
     
  6. Dec 21, 2009 #5

    fluidistic

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    Re: Heat

    Yeah I find very strange that you have no idea about the answer. Also, the experiment is quite easy to do (you only 2 glasses of water + a fridge).
    Then putting the same finger in each glass should tell you the answer.
     
  7. Dec 21, 2009 #6
    Re: Heat

    The real question is why is it that hot water will make ice-cubes faster than cold water...
     
  8. Dec 21, 2009 #7

    fluidistic

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    Re: Heat

    Oh... then it's a totally different question!
    It has been discussed in this forum and I'm pretty sure more than once.
    Read http://en.wikipedia.org/wiki/Mpemba_effect.
     
  9. Dec 21, 2009 #8

    DaveC426913

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    Re: Heat

    It won't.

    Except in very carefully-controlled circumstances.
     
  10. Dec 21, 2009 #9
    Re: Heat

    ok if the room was 20°C warmer what would the answer be ?
     
  11. Dec 21, 2009 #10

    fluidistic

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    Re: Heat

    You definitely didn't read the link I provided... There are many more parameters than the room temperature to take into account.
     
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