Re: Chez Watt: There can be no Evolution by natural selection DJT

On Oct 29, 2:44 pm, Rusty Sites <SpameYou...@xxxxxxxxxx> wrote:
Christopher Denney wrote:
On Oct 28, 7:44 pm, Rusty Sites <SpameYou...@xxxxxxxxxx> wrote:
Christopher Denney wrote:
On Oct 27, 7:45 pm, Rusty Sites <SpameYou...@xxxxxxxxxx> wrote:
the heekster wrote:
On Sat, 27 Oct 2007 13:47:43 -0700, Rusty Sites
<SpameYou...@xxxxxxxxxx> wrote:
the heekster wrote:
On Fri, 26 Oct 2007 15:58:19 -0700, Rusty Sites
<SpameYou...@xxxxxxxxxx> wrote:
the heekster wrote:
On Sun, 21 Oct 2007 20:19:29 -0700, Ken Shackleton
<ken.shackle...@xxxxxxx> wrote:
On Oct 21, 8:09 pm, the heekster <heeks...@xxxxxxxx> wrote:
On Sat, 20 Oct 2007 19:15:58 -0700, Harry K <turnkey4...@xxxxxxxxxxx>
wrote:
On Oct 20, 6:28 pm, Harry K <turnkey4...@xxxxxxxxxxx> wrote:
On Oct 20, 5:37 am, Ernest Major <{$t...@xxxxxxxxxxxxxxxxx> wrote:
In message <1192817121.229225.42...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, Harry
K <turnkey4...@xxxxxxxxxxx> writes
On Oct 19, 10:21 am, John Vreeland <vreej...@xxxxxxxxxxxx> wrote:
On Wed, 17 Oct 2007 17:54:18 -0700, Bob Casanova <nos...@xxxxxxxx>
opined:
On Tue, 16 Oct 2007 21:10:44 -0700, the following appeared
in talk.origins, posted by Kent Paul Dolan
<xanth...@xxxxxxxx>:
File under "Anti-Eureka!":
OK I believe that also, but if Ice
shrinks when it melts the sea level
will become lower when the Ice shrinks.
hot higher..
Ye chaos, that such stupidity can even
support respiration...
I'd guess Archimedes is up to about 3000rpm by now...
I heard that Rush Limbaugh made this claim on the air, once.
For the record, when fresh-water ice (pack ice is fresh) melts in salt
water, the water level rises. Of course, most ice is land-locked,
anyway, so there is no question of its raising sea level when it
melts. And then, of course, the fact that warming water expands...
But if we want to indulge in exploring ephemera, how about the fact
that increased world-wide prosperity will result in more boats being
in the water, which can only result in more water being displaced?
Why is this cross-posted to misc.misc? deleted.
--
Two Creation Scientists can hold an intelligent conversation, if one
of them is a sock puppet.
---John Vreeland(IEEE.org) http://rtmabc.blogspot.com
See discussion with Ken Shackleton. Logic says that the level won't
change as the cube displaces enough salt water to balance the mass of
fresh water contained in the ice. Same happens after the cube melts.
I am setting up an experiment to try but would like a cite if there is
one.
Harry K
A thought experiment -
Consider a hundred square miles of ice of uniform thickness floating on
the ocean, coated by a rigid covering of negligible mass. The surface of
the ice is above that of the ocean, due its lower density. Then
instantly turn the ice to fresh water. Because its still of lower
density than the ocean, and is constrained from flowing away, the
surface of the fresh water is still above that of the ocean, although
lower than that of the ice. Finally remove the coating. The freshwater
will flow outwards raising the surface of the surrounding ocean.
--
alias Ernest Major- Hide quoted text -
- Show quoted text -
Ice floats with almost all of its mass under water. This a a rather
wierd way to look at it but it is accurate as to the result: The melt
water exactly fills the hole the ice occupied prior to melting. That
is true no matter what the ice is floating in.
Try doing the experiment.
Harry K- Hide quoted text -
- Show quoted text -
After rethinking that, the light dawned. Pictured cube floating in/on
mercury. Yep, the level rises.
Harry K
Consider that ice is about 8% less dense than water. For a freshwater
iceberg, and salt water, that difference is probably about 13% less
dense. This means that the berg will float higher in the water.
When it melts, it should fill the volume it displaced.
By your own numbers, there will be 5% left over once the "hole"
displaced by the iceberg is filled by meltwater.
Well, maybe so, but icebergs are even less dense than an ice cube,
because 'bergs have a lot of air trapped in them
Trapped air would make no difference. The iceberg would displace the
same amount of water with or without the air and the air would escape
into the atmosphere upon being released.
Displacement is a function of mass.
You appear to be arguing that trapped air in an iceberg is massless.
Displacement by a floating object is a function of its weight.
And weight is mass times the acceleration. Here, the acceleration is
gravity.
Air has
no weight because it is floating.
Your education is sorely lacking. Air has mass, and consequently,
weight.
How would you propose to weigh air in air? I am educated enough to know
that the weight of the atmosphere manifests itself in pressure.
Pressure is a scalar. It has no direction associated with it. It acts
equally in all directions.
The amount of fluid displaced by a
floating object does not depend on how its mass is distributed through
its volume.
No one said that it did.
My argument follows from that single fact.
That means you can move the air pockets around in the
iceberg without changing the amount of water it displaces.
Chez Watt?
Move all the
air to the top of the iceberg so that it has two layers.
This is absurd on its face.
It is demonstrating the absurdity of what you are saying.
It has ice
below and air above. The amount of water displaced has not changed.
So, you change the density of the object, by removing the mass of the
air, and you think nothing has changed?
I didn't say nothing had changed. I said the amount of water displaced
has not changed. Since you have agreed that the distribution of mass in
a floating object makes no difference, I could just declare any amount
of air lying above an iceberg to part of the iceberg. Obviously, such a
declaration does not change the amount of water displaced by the
iceberg. If you don't like that, I could take a slightly more
complicated approach. Suppose all the air in the iceberg is in one big
pocket at the top. I will make the iceberg cubic for simplicity. Now
suppose that there is a thin shell of ice around the top and sides of
the pocket. If the shell is made thinner and the ice that is removed
from the shell is placed somewhere else in the iceberg, only the
distribution of the matter in the iceberg is being changed, so the
amount of water displaced does not change. In the limit, as the shell
becomes thinner and thinner, the air pocket just becomes part of the
air. When does the amount of water being displaced by the iceberg change?
Do your experiment in reverse, with the air at the bottom. Here's a
hint, at the same time.
First, let's do a vacuum at the bottom and no atmosphere above the
water. The iceberg has the same weight, so it displaces the same amount
f water. Now make the bottom part air. This would add weight to the
iceberg, but it also puts more of the iceberg above the water. The
extra part above the water displaces its volume in air which produces a
buoyant force equal to its weight in air. Equilibrium will occur when
the extra volume of air added at the bottom equals the added volume
above the water. Of course, this is all assuming that the air in the
iceberg is at atmospheric pressure.

The displacement of an object depends only on how much volume is
enclosed by it's surface.

If the object is floating, it depends only on the weight of the object.
If it is submerged, then the displacement only depends on its volume.

If an object floats in water it's because it's density is less than
that of the water it's floating in.

Your experiment is both changing the density of the object, and it's
total volume.

Yes, but the point was that adding air to the iceberg does not change
the amount of water is displaces.

Actually it does, the iceberg is bigger because of the trapped air,
than it would be if it had no trapped air.
The trapped air displaces ice that would otherwise occupy it's volume.
Thus the density of the iceberg is less than just ice. (i.e. it's
bigger for the same mass of ice)
Thus the amount of water, per unit mass, displaced is increased.
That means that for every unit of mass of ice, the iceberg with air
trapped will ride higher in the water than the same mass of ice with
no air trapped, because it is less dense.

A real good demonstration, imagine a solid lead ball, will is sink or
float in water?
Now form that solid ball into a sphere that is hollow, using the same
mass of lead.
Amazingly it floats, why? Because the mass of the water it displaces
is more than the mass of then lead(and air).
The system is less dense because it has air trapped inside, the hollow
sphere is bigger than the solid one.

.

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