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DPCrisp
In: Bedfordshire
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| Neither the Sun nor Jupiter turns by force of momentum alone. There appears to be an internal power driving the rotation of the gas giants from the inside out. |
Or quite the opposite.
| That said, most of the rotational energy may still be attributable to momentum. |
Not sure what you mean by that. (Angular) momentum isn't a cause of (rotational) energy.
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Ishmael
In: Toronto
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| DPCrisp wrote: | | Or... We don't know what's happening inside. Is the outside/equator being driven fastest? Is the inside/pole being held back? Depends which scenario can actually be explained. |
How about this.
The only part of a star we know to be solid is the iron core.
What if the core is spinning? Simple friction between it and the surounding material should be enough -- in the vacum of space -- to get the rest of the mass to spin at the same speed as well.
The Law of the Conservation of Angular Momentum, however, is sufficient to ensure that the more distant material never quite spins as fast as the stuff nearest the center. What you get looks like a series of inset cylinders, surrounding a central pole, with each cylinder spinning at a slightly slower rate than the one just inside.
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Ishmael
In: Toronto
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| DPCrisp wrote: | | That said, most of the rotational energy may still be attributable to momentum. |
Not sure what you mean by that. (Angular) momentum isn't a cause of (rotational) energy. |
I think I beg to differ.
Once you start a body spinning, it isn't quick to stop.
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Mallas
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How do we know the core of the Sun is iron?
I mean, isn't the core of the Earth being iron just an assumption?
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Ishmael
In: Toronto
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| Mallas wrote: | | How do we know the core of the Sun is iron |
We know what the cores of stars are made of because you are sitting on one.
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DPCrisp
In: Bedfordshire
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| The only part of a star we know to be solid is the iron core. |
Well, you might suppose the nuclear fusion is carrying on around the growing surface of an iron ball... but why would the iron solidify?
| What if the core is spinning? |
Why would it? As a cause of everything else spinning, I mean. A ball of pure hydrogen would be spinning before it even lights up, let alone by the time it's produced an appreciable amount of iron.
| Simple friction between it and the surrounding material should be enough -- in the vacuum of space -- to get the rest of the mass to spin at the same speed as well. |
Except that the friction would slow it down unless it's driven somehow. And the rest isn't going at the same rate.
Are you thinking of central layer going at the same rate as the core, with a bit of slippage between successive layers leaving the poles going slowest? But why would there be slippage? As with stirring soup, it should all end up at the same rate unless the layers are being held back or the core is always accelerating.
| What you get looks like a series of inset cylinders, surrounding a central pole, with each cylinder spinning at a slightly slower rate than the one just inside. |
OK, not discs then. But this is the opposite of the actual picture: the equator goes fastest.
| Once you start a body spinning, it isn't quick to stop. |
Certainly -- you need a reason (a force) to speed up or slow down -- but momentum and energy are peers, so to speak: for a given mass, a certain velocity means a certain momentum and a certain kinetic energy. (In rotational terms, for a given moment of inertia, a certain angular velocity means a certain angular momentum and a certain rotational kinetic energy.) "Rotational energy is attributable to momentum" would be a queer thing to say: they both come from whatever forces set the thing going at the given rate.
| We know what the cores of stars are made of because you are sitting on one. |
That doesn't mean anything Earth-like exists at the centre of the Sun: only that in going out, Suns become Earth-like.
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Ishmael
In: Toronto
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| DPCrisp wrote: | | What you get looks like a series of inset cylinders, surrounding a central pole, with each cylinder spinning at a slightly slower rate than the one just inside. |
OK, not discs then. But this is the opposite of the actual picture: the equator goes fastest. |
oh.
silly me!
my mistake :-)
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Boreades
In: finity and beyond
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I empathise with much that has been said, but (surely) if we are thinking in terms of an iron sun and an electric universe, it is not Newtonian equations that matter, but those of Faraday, Maxwell, etc.
Things like the Right-Hand Rule. If there is an electric current flowing axially in the sun, then there must be a magnetic field at right angles to that,
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Ishmael
In: Toronto
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What are these equations?
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Boreades
In: finity and beyond
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| Ishmael wrote: | | What are these equations? |
Faraday's contribution was to devise a Law Of Induction which predicts how a magnetic field and an electric circuit will interact to produce an electromotive force (EMF)
Maxwell's most famous achievement was to create a set of equations that describe electricity, magnetism, and optics as one and the same thing, using a molecular vortex model of Faraday's law.
The Right Hand Rule is a nmemonic that makes it easier for simple folks like us to picture what these mathematics are describing in symbols.
Albert Einstein later said:
The precise formulation of the time-space laws was the work of Maxwell. Imagine his feelings when the differential equations he had formulated proved to him that electromagnetic fields spread in the form of polarised waves, and at the speed of light! To few men in the world has such an experience been vouchsafed ... it took physicists some decades to grasp the full significance of Maxwell's discovery, so bold was the leap that his genius forced upon the conceptions of his fellow workers.
Originally, Maxwell produced a set of 20 equations. As Maxwell was decades ahead of his colleagues in understanding, they needed a simplified or truncated version of Maxwell's equations, devised by Oliver Heaviside, to understand some of what he meant. The simpler version is good for local conditions, but it ignore two of Maxwell's key concepts of electric potential and magnetic potential. Which, years later, are accepted in quantum theory, but still ignored as part of Maxwell's greatest work.
The history of his equations is a fascinating subject in itself. Interestingly, Tom Bearden maintains that it is because of this truncation that most (if not nearly all) physicists just cannot understand how zero-point energy and over-unity devices might work.
All of this chould be a part of the AEL "Everything you thought you know is wrong" series (or whatever it gets called in the end). See: http://www.cheniere.org/correspondence/030706.htm
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Boreades
In: finity and beyond
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Is there a physicist in the house?
Faraday's law of induction is a basic law of electromagnetism predicting how a magnetic field will interact with an electric circuit to produce an electromotive force (EMF)�a phenomenon called electromagnetic induction. It is the fundamental operating principle of transformers, inductors, and many types of electrical motors, generators and solenoids.
The Earth is a giant magnetic, sitting in a huge electric field supplied by the Sun.
Does that produce electromagnetic induction?
Is it of sufficient force to produce a torque vector on the Earth?
If so, which direction would it make the Earth rotate?
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Chad
In: Ramsbottom
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The electric field produced by the Sun is a plasma field (it's electrickery Jim... but not as we know it) so basically it's just a cloud of hydrogen gas ejected from the sun, in which the negatively charged electrons have been split away from the positively charged protons.
These separated, ions coexist randomly within the plasma cloud but the overall state is one of quasi-neutrality.
http://www2.warwick.ac.uk/fac/sci/physics/current/teach/module_home/px384/lecture_04.pdf
Faraday's laws apply only where an electric current is flowing (a stream of ions, all carrying the same charge, flowing in the same direction) which will give an electromotive force in a predictable direction.
While the electrically ionised particle in the Sun's plasma cloud will interact with the Earths magnetic field, the overall neutrality of the plasma cloud will mean no electromotive force will be induced in the Earth.
(Unless of course, the plasma cloud is not actually neutral.... )
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Boreades
In: finity and beyond
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Err, I thought you just said the plasma is positively charged protons?
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Chad
In: Ramsbottom
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Err, didn't I also mention negatively charged electrons?
They've been split away from the protons, but still remain within the plasma... which should (in theory) contain an equal number of positive and negative ions.
(Sorry... I didn't make that very clear.)
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Boreades
In: finity and beyond
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Err, yes you did. My most grievous fault for not reading it properly.
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