Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: percepts on 13/04/2014 14:25:45
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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?
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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?
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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
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... 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.
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
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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?