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Re: [Phys-L] Figuring Physics solution Jan 2018



I don’t think enuff info.

At one extreme no bubbles (He-4 < ~ 4K); bottom of cylinder heated rest insulated, and bubbles only at bottom (w/ nuclesation sites none on walls)

bc

On 2018/Jan/23, at 13:08, brian whatcott <betwys1@sbcglobal.net> wrote:

Robert Cohen wrote in part:
/snip/
I'll start with the simple situation of a gas in a one-dimensional container
(so the particles only travel along that one dimension),
made up of particles of identical speeds under no attraction and totally
elastic collisions. That way the speeds remain identical.

I then add a small attraction so that if I remove the "top" of the
container, the fluid doesn't necessarily spit out the top. This can then be
considered a liquid. The speeds won't always be identical at any given time
but on average they are.

At any given time, only the particle at the top is exposed to the vacuum
above and thus only that particle can "leave" the liquid state and fly away
as a free particle. /snip/

This conflicts with my image of a water column boiling at 20+ degC
when exposed to vacuum. I visualize bubbles nucleating at all levels,
NOT just at the surface.

Brian W
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