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Author Topic: stirring my photo chemicals  (Read 1338 times)

Offline percepts

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stirring my photo chemicals
« on: 13/04/2014 14:25:45 »
As I understand it, gravity causes the planets and galaxies to conglomerate into what they are. i.e. solid mass and it's garvitional pull that brings it all together.

So when I'm mixing my photo chemicals in a jug and stirring it, the undissolved chemical is drawn together into the center just as though it were gravity pulling it all in. But it isn't gravity, or is is it?  It seems the spinning motion creates a force of some kind that causes the chemical grains to be drawn together. Is this akin to gravity or not? Does spin in galaxy create gravitational pull?


 

Offline CliffordK

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Re: stirring my photo chemicals
« Reply #1 on: 13/04/2014 18:12:34 »
How are you mixing the photo chemicals?  By moving the container in a circular fashion? 

That sounds like you are using centrifugal force for the mixing process, and mixing them along the outside of the container rather than the middle. 

Isn't that the opposite of your gravity analogy?
 

Offline percepts

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Re: stirring my photo chemicals
« Reply #2 on: 14/04/2014 03:39:23 »
No, put a few grains of grit/sand in water in a flat bottomed jug and stir it in a circular motion and then leave it. The grit/sand will move to the center.

AND

The centrifugal force of a spinning galaxy should make the stars move outwards but it doesn't
« Last Edit: 14/04/2014 04:02:44 by percepts »
 

Offline RD

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Re: stirring my photo chemicals
« Reply #3 on: 14/04/2014 04:38:36 »
... put a few grains of grit/sand in water in a flat bottomed jug and stir it in a circular motion and then leave it. The grit/sand will move to the center.

Quote from: wikipedia.org/Vortex#Pressure_in_a_vortex
The fluid motion in a vortex creates a dynamic pressure (in addition to any hydrostatic pressure) that is lowest in the core region, closest to the axis, and increases as one moves away from it, in accordance with Bernoulli's Principle
http://en.wikipedia.org/wiki/Vortex#Pressure_in_a_vortex

That's why the particles are concentrated in the centre of stirred the cylindrical jug.
Same as bubbles/smoke trapped in toroidal vortexes ...

The centrifugal force of a spinning galaxy should make the stars move outwards but it doesn't

allegedly "dark-matter" is responsible anti-intuitive galaxy shape ... http://en.wikipedia.org/wiki/Galaxy_rotation_curve
 
« Last Edit: 14/04/2014 06:32:35 by RD »
 

Offline percepts

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Re: stirring my photo chemicals
« Reply #4 on: 16/04/2014 11:11:40 »
is this vortex pressure differential applicable to rotating galaxies? i.e. is there some field (local to the galaxy) in rotation causing a pressure differential, perhaps creating gravity or am I barking up the wrong tree.

And how fast does a black hole rotate? Fast enough to generate a massive pressure differentail?
« Last Edit: 16/04/2014 11:14:36 by percepts »
 

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Re: stirring my photo chemicals
« Reply #4 on: 16/04/2014 11:11:40 »

 

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