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Is this a myth? Pyrmaids replace fridges?

  1. Aug 4, 2011 #1
    I heard it when i was little from TV.

    Is it true that you can put food into a box in the shape of a pyramid with a sqaure base and it will work like a fridge?

    How does it work? Why does it work? Is this true or just really mean hoax?
     
  2. jcsd
  3. Aug 4, 2011 #2

    xts

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    You must try it. I suggest to use piece of meat (or fish - it also smells well) and keep the pyramid in your bedroom.
     
  4. Aug 4, 2011 #3

    DaveC426913

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    Let's default to myth until there's any evidence to support it.

    Actually, lets default to 'who knows' until we even have some facts about the claim. How big? What material? What configuration? What conditions?
     
  5. Aug 4, 2011 #4
    No I mean jsut a pyramid made of cardboard
     
  6. Aug 4, 2011 #5

    Ryan_m_b

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    Staff: Mentor

    A pyramid made of cardboard? I'm going to call myth on this one. If the air temperature is (as it was in London yesterday) 30 degrees how is a cardboard pyramid going to cool to the 4 degrees that my fridge is kept at?
     
  7. Aug 4, 2011 #6
    I think it only works for warm food like bananas or last night's left overs. I mean it obviously isn't going to work for ice creams
     
  8. Aug 4, 2011 #7
    Just a mean hoax. Unless it is (a) located inside a fridge or (b) located in outer space.

    Otherwise it would overturn all of thermodynamics....and revolutionize most of science as well.
     
  9. Aug 4, 2011 #8
    Mythbusters tried it, and they came to the conclusion that nope, doesn't work for food, doesn't work for sharpening blades, doesn't work for something else that I can't remember.
     
  10. Aug 4, 2011 #9

    DaveC426913

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    Yeah: matter.

    :biggrin:
     
  11. Aug 4, 2011 #10
    Sometimes memories from when we were a kid are distorted. They seem very real but they are not actually what happened.
     
  12. Aug 4, 2011 #11

    FlexGunship

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    Art%20Model%20Award.jpg

    EDIT: The answer is no. The temperature inside of a pyramid-shaped cardboard box will not significantly differ from ambient temperature as there is no means to overcome entropy. There might be a very small gradient from the bottom of the box to the top of the box given that cooler air is more dense and will tend to settle on the bottom, but even that will equalize over time due to Brownian motion.

    Ask yourself the reverse: could you make an oven out of an upside-down pyramid box? And if so, could you make it large enough that the resultant heat would exceed the combustion threshold for the material? And if so, does that mean that you could make a SHAPE that, when properly scaled, is combustible?

    Opinion and commentary: I love crazy ideas.
     
    Last edited: Aug 4, 2011
  13. Aug 4, 2011 #12

    Hepth

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    The only thing I could see is that it acts as a bread-box, blocking sunlight and other sources of light that would promote cell growth of fungi/mold/etc exactly as a breadbox does. The shape shouldn't matter, but perhaps people that "tried" this with say, a piece of bread, would notice a drastic increase in shelf life from a piece of bread sitting in the open.
     
  14. Aug 4, 2011 #13

    DaveC426913

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    You cannot extrapolate this.

    Me, I was imagining some sort of heat sink, placing the bulk of the volume in contact with a convective cooling surface.

    Again, if we were to give this its due (which is way more than it deserves), we'd need the details of the claim.
     
  15. Aug 4, 2011 #14
    I'm guessing that some comment about the cool interior of a pyramid versus the blistering heat of the desert outside snowballed into the fanciful claim that it's like an air conditioner, and thus capable of keeping food cold.
     
  16. Aug 4, 2011 #15
    I won an award guys!
     
  17. Aug 4, 2011 #16
    So how do food in the real pyramids store food?
     
  18. Aug 4, 2011 #17

    DaveC426913

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    I'm detecting an attempt at humour here...
     
  19. Aug 4, 2011 #18

    Pythagorean

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    Fire Tetrahedron Dislikes!!

    [URL]http://upload.wikimedia.org/wikipedia/commons/9/99/Fire_tetrahedron.svg[/URL]
     
    Last edited by a moderator: Apr 26, 2017
  20. Aug 4, 2011 #19
    http://www.hpb.gov.sg/uploadedImages/HPB_Online/Health_Topics/Food_for_Health/Healthy_eating_-_the_basics/Healthy%20Diet%20Pyramid.jpg

    This pyramid seems to be keeping food quite nicely...
     
  21. Aug 5, 2011 #20

    phinds

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    2016 Award

    Uh ... it was "anything"
     
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