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Boiling eggs

  1. Jul 10, 2009 #1
    If it takes 10 min to hard boil 1 egg, how long will it take to boil 2?
     
  2. jcsd
  3. Jul 10, 2009 #2

    Danger

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    10 minutes.
     
  4. Jul 10, 2009 #3
    why?
     
  5. Jul 10, 2009 #4

    berkeman

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    Why not?
     
  6. Jul 10, 2009 #5
    Well, first of all, I think when you have two eggs you need less volume of water to cover them (if you boil them in a cup) =) so the water will get heated faster. On the other hand transformation from an ordinary egg to hard-boiled egg is some kind of phase transition, so I guess it will take energy, and two eggs will take two times more energy than one.

    So what would your answer be if I asked how long will it take to boil 100 eggs?
     
  7. Jul 10, 2009 #6

    russ_watters

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    10 minutes and a bigger pot.
     
  8. Jul 10, 2009 #7

    Danger

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    :rofl:
     
  9. Jul 10, 2009 #8
    How much does the second egg lower the temperature of the water?
     
  10. Jul 11, 2009 #9
    Does it not take more energy to heat two eggs rather than one egg? I always thought a larger egg will take more energy to heat the internal temperature than a smaller egg. Similarly, a larger pot of water should take more energy to raise to the same temperature, shouldn't it? :\
     
  11. Jul 11, 2009 #10

    berkeman

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    Sure. But that wasn't the original poster's (OP's) question. That's why we're playing with them a bit.
     
  12. Jul 11, 2009 #11

    Danger

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    Despite the loss of W, I'm very happy to be back in my own house because it has a gas stove. The one in our apartment is electric. I hate those things.
    I have the recipe for the absolutely perfect boiled egg, using a gas stove. I cook 3 at a time, because that's all that my little pot will hold. Add some salt, to cauterize any cracks, fill the pot to covering the eggs by a cm or so with the hottest water from the tap. Put it on max flame until it starts to boil, then turn the burner to the lowest possible flame, pop on a lid, and simmer for exactly 7 1/2 minutes. Then quench in cold water. Perfect.
     
  13. Jul 11, 2009 #12

    DaveC426913

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    Excellent. Now we have empirical data.
    One egg takes 11 minutes.
    Three eggs take 7 1/2 minutes.

    Therefore 2 eggs take exactly 9 minutes 15 seconds.

    QED.
     
  14. Jul 11, 2009 #13

    Danger

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    Sometimes I truly wonder about you, Dave. :biggrin:
     
  15. Jul 11, 2009 #14

    HallsofIvy

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    Put one egg in a pan of water and put them on a burner. Put the other egg in a second pan of water and put it on a second burner. Turn them both on. Ifr it takes 10 min to hard boil 1 egg, it will take 10 min to hard boil 2 eggs (or 3 eggs up to however many burners you have on your stove!

    If that was not what you meant, then ask an intelligible question!
     
  16. Jul 11, 2009 #15
    I don't suppose it really matters how many eggs you put in the pot. If I remember correctly, water maintains a constant temperature while boiling, so as long as the water is boiling, all of the eggs should be getting the same amount of heat. Adding eggs may make it so that it requires more energy to keep the water boiling, but as long as it is boiling, it will take ten minutes regardless.
     
  17. Jul 11, 2009 #16

    DaveC426913

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    Then you'll really start to wonder when I tell you how long it takes to boil 8 eggs... :tongue2:
     
  18. Jul 11, 2009 #17

    turbo

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    I boiled 42 eggs once. I can't tell what happened - copyright issues, mostly.
     
  19. Jul 11, 2009 #18

    Danger

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    Does it involve boiling water, or did you just paint them with your salsa?
     
  20. Jul 12, 2009 #19
    I can't believe I forgot that. Thanks for answering my personal question.
     
  21. Jul 12, 2009 #20
    It seems we need much more time to discuss egg boiling than to boil eggs itself.
    Acccording to me, boiling 1 or 2 eggs can be very close, say 7 min if you start from boiling water. If you start from ambient temp, boiling 2 can be a little bit longer say 5 and 6 min.
    That's because the outer shell of an egg conducts heat very badly when it is boiled.
    When you start at 100 oC (put in the egg when water boils), the outer shell (not the yolk) is boiled and hardened so the yolk is almost insulted and you lose most of the heat from the stove, only small percentage is used for cooking the eggs. So 1 or 2 eggs make almost no difference.
    If you start at ambient, the egg outer shell can still conduct heat much better than when it is cooked, so 1 or 2 eggs can be different in time.
    If the pot is very big compared to the egg, the difference is negligible
    .
    .
    I have no experience of boiling more than 3 eggs
     
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