Curious phase transition


by flicflex
Tags: curious, phase, transition
Dickfore
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#37
Dec16-12, 11:58 AM
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Quote Quote by flicflex View Post
solid gaz,
This is an oxymoron.
AlephZero
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Dec16-12, 01:49 PM
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Quote Quote by flicflex View Post
But why does the materia doesn't accumulate anymore (isn't solid anymore) beyond that greatest gravitational potential field (6400km)?
Mateiral is still accumulating, at a rate of about 10,000 to 20,000 tons per year. http://en.wikipedia.org/wiki/Micrometeoroid
snorkack
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Dec16-12, 04:19 PM
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Quote Quote by Borek View Post
No.

Mass & radius of a planet are in a way random and depend on the initial conditions in the system from which the planet emerged. They are easy to measure and they are the basic input data used to build the planet model. You can't use other data to predict mass & radius, as you don't have the other data.
They are not independent.

You cannot predict mass from radius without knowing composition. With mass and composition you can predict radius - reasonably easy at intermediate masses, gets harder at low and high masses. The radius does depend on internal heat (slightly).

Now, as for "phase change"...

The surface of ground is NOT generally at 0 altitude. The surface of water is.

When you look at water surface, you commonly see two, and even three transitions, depending on weather.

Counting from up to down, you will find mostly gaseous air, then mostly solid water, then mostly liquid water, then mostly solid rock.

The smallest composition contrast is the one between mostly solid water and mostly liquid water.

But before you single that out as a phase transition in contrast to the other two transitions, note that the liquid water contains significant amounts of liquid (dissolved) rock, which is missing in solid water, and smaller but also significant amounts of liquid (likewise dissolved) air.

The mostly gaseous air above contains significant amounts of gaseous water. And the mostly solid rock contains significant amounts of liquid water, as well as liquid (dissolved) rock and liquid (dissolved) air.
Borek
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Dec16-12, 05:05 PM
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Quote Quote by snorkack View Post
You cannot predict mass from radius without knowing composition. With mass and composition you can predict radius - reasonably easy at intermediate masses, gets harder at low and high masses. The radius does depend on internal heat (slightly).
I never stated you can predict them. And the way I see it composition is a function of the initial conditions.


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