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Totally OT: Doctor Science Question

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  • Totally OT: Doctor Science Question

    What causes this?






    Gary
    Gary


    Appearance is Everything...

  • #2
    Freezing ice uphill ?

    .
    .

    Sir John , Earl of Bligeport & Sudspumpwater. MBE [ Motor Bike Engineer ] Nottingham England.



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    • #3
      LOL....Yup...but the drop is less than it would be if level.
      Jim

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      • #4
        This might take thier mind off ballistics lol
        Ernie (VE7ERN)

        May the wind be always at your back

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        • #5
          Ice is crystalline. That is an extended ice crystal. Look at some photos of hoar frost and you will see the resemblance.

          Free software for calculating bolt circles and similar: Click Here

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          • #6
            Did you drop your Viagra in the freezer again?
            I just need one more tool,just one!

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            • #7
              ice spike

              Hello

              Look at this

              http://ffden-2.phys.uaf.edu/212_spri...ormations.html

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              • #8
                The frost is formed by sublimation, crystals forming from water vapor.

                That seen in the ice tray is frozen liquid water.
                I see that often when I dump my ice trays.

                The plastic trays are stacked in the freezer, and the one above has a slow drip leak.
                Last edited by lynnl; 12-21-2009, 02:49 PM.

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                • #9
                  Here's something "similar":





                  It's called "needle-ice".... very interesting physics behind the formation. Evan can explain



                  Another formation in Mud :



                  Boths pics from in my yard earlier this year.
                  Last edited by lakeside53; 12-21-2009, 02:55 PM.

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                  • #10
                    I think that the original poster's answer is that the feature is an extrusion of ice, likely formed when the original ice froze a skin all around the cube and the remaining water expanded on freezing. This might cause some of the water on the inside of the cube to extrude out and freeze during the extrusion.

                    That's about all I can think of, anyway.

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                    • #11
                      beats the hell outa me.
                      It's only ink and paper

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                      • #12
                        I would agree with Rkepler.
                        The water inside the icecube would be Lower than 32 deg(F) because it is under pressure, and then when the pressure is released (rupture) it would freeze immediately at atmospheric pressure.

                        The weird thing is
                        No signs of rupture?
                        Diagonal leaning ?

                        Not knowing all the conditions makes these a guess.
                        Rich

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                        • #13
                          do you have a small drip from above the ice tray? maybe the top part of your freezer is warmer, condensing the cool air, and there happen to be a low spot on the fridge's inner paneling... one drop at a time, freezing, follow by another drop. so on

                          edit: just saw the "ice spike" link. looks like my theory is completely wrong

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                          • #14
                            Rkeps got it, extrude freezing, very simple physics as ice expands when freezing and can even "crowd" the inner res. of what little water is left, the water finds the weakest crust and starts protruding.

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                            • #15
                              The problem with the xpanding on freezing hypothesis is that water starts expanding before it freezes. The maximum density of water occurs at 39.2 degrees F. As it cools below that temperature it expands. When it reaches the temperature called the triple point just above the freezing temperature the water may consist of vapour phase, liquid phase and crystal phase simulataneously. However, there is a very big joker in the deck, actually several of them. First, still water will supercool and stay liquid well below the freezing temperature. The cleaner and smoother the tray is the further it may super cool. Water can be supercooled under normal pressure to at least as low as -40 and perhaps all the way to absolute zero without turning to a crystalline solid.

                              Answering a question such as this dealing with water immediately runs into the problem of the very anomalous properties of water. It simply does not follow the "rules" that apply to nearly all other substances as they change phases with temperature. Water has at least something like 15 to 20 known distinct states some of which are entirely stable at what we consider to be ordinary temperature. It has even more metastable states that may exist temporarily and that are exceedingly sensitive to slight variations in the makeup of the water and the environment. Not just the current environment but also the environmental history of a sample is important.

                              For instance, the freezing of water will depend on the temperature from which it cools to start with. A sample that cools from boiling temp and a like sample that cools from room temp will have different freezing times even if compared when they are at the same temperature. It is actually possible for hot water to freeze faster than cold water due to something called the Mpemba effect.

                              As for this particular example, it isn't likely due to an increase in internal pressure caused by freezing. When water freezes it releases a great deal of heat which would prevent such a feature from being formed. It's called the Latent Heat of Crystallization. The more likely explanation is the reverse process of sublimation, called deposition, in which water vapour turns directly to ice without going through the liquid phase. Given a seed crystal if the conditions are just right water can grow perfect crystals that are hexagonal cylinders.
                              Last edited by Evan; 12-21-2009, 05:30 PM.
                              Free software for calculating bolt circles and similar: Click Here

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