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Thread: WHAT IS THE CAUSE OF EARTH'S ROTATION ABOUT IT'S OWN AXIS?

  1. #1 WHAT IS THE CAUSE OF EARTH'S ROTATION ABOUT IT'S OWN AXIS? 
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    I KEEP ON THINKING OF PHENOMENONS I CAN'T EXPLAIN.. CAN ANYONE EXPLAIN THIS ONE.. PLEASE...

    HELP ME.... PLEASE.................................


    I won't die until i find out where i m gonna go after dying..... and I KNOW PHYSICS IS GONNA HELP ME FIND IT OUT.
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    It is a relic from the formation of our solar system. As I already explained in a different thread, in the beginning everything in the universe has a slight rotation, how small it may be. This often a result of encounters of - let's say - gas clouds that attract each other by gravity.

    From such gas clouds that always also contain about 1% of dust, the stars form by gravitational collapse. Certain density and temperature conditions must be fulfilled so that a cloud can collapse by self gravity, i.e. the inner denser parts pull at the outer parts. Like an ice skater who pulls in his arms in order to increase his rotation, such clouds spin faster and faster during the collapse. The resulting centrifugal force in part compensates the gravity leading to the formation of a disc in the plane of the equator of the rotation. The centre forms the star, the disc is the material that forms planets.

    The disc material is viscous, i.e. there is friction leading to local eddies that rotate inside the disc that itself rotates around the future star (called protostar). Through a process that is not yet well understood, these rotating eddies collapse themselves under self-gravity forming planets. The rotation that these proto-planets have survive the planet formation phase. As a result the planet rotates, because the local densification from which it ermerged inside the early viscous disc rotated. I hope, I was able to explain it.


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    earth probably started rotating from all the asteroids colliding with it.
    when you have eliminated the impossible, whatever remains, however improbable, must be the truth
    A.C Doyle
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    dejawolf,
    read Dishmasters explanation. It is the correct one. Doubtless the impacts of comets and asteroids effected the rotation, but they did not cause it. The impact of a Mars sized planetesimal that is believed to have created the moon, probably also led to the high initial rotation rate - six hours or less.
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    I think the entire bodies in universe rotate. Where does the energy come from? When will they exhaust? The Sun & Moon put lot of tidal force on earth. Even then the rotation survived for such a long period?
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    Universal Mind John Galt's Avatar
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    Energy can neither be created or destroyed. (We shall ignore transformation to matter and vice versa.) The energy of rotation, expressed as angular momentum, in any system must remain the same. All that happens with the tidal interaction of the Earth and the moon is that the Earth slows down (losing angular momentum) and the moon moves further away (gaining angular momentum).
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    How noticeable is that effect? How many meters per year (if not Km) does the moon move away, and how much velocity does the earth lose per year?
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

    -Einstein

    http://boinc.berkeley.edu/download.php

    Use your computing strength for science!
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    Quote Originally Posted by Cold Fusion
    How noticeable is that effect? How many meters per year (if not Km) does the moon move away, and how much velocity does the earth lose per year?
    The moon distance increases by 3.8 cm every year. This has an effect on the Earth's rotation that the day is prolonged by 23 microseconds per year. Another counter effect reduces this to a net value of 17 microseconds per year. This does not seem much, but it sums up to quite a number if calculated back to millions of years in the past. Remember: 86400 seconds roughly make a day.
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    thats not much at all. it basically means when the dinosaurs died out, earth spun about 18 minutes slower.
    when you have eliminated the impossible, whatever remains, however improbable, must be the truth
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    Quote Originally Posted by dejawolf
    thats not much at all. it basically means when the dinosaurs died out, earth spun about 18 minutes slower.
    Faster. It slows down. The days were shorter then.
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    Quote Originally Posted by Dishmaster
    Another counter effect reduces this to a net value of 17 microseconds per year. This does not seem much, but it sums up to quite a number if calculated back to millions of years in the past. Remember: 86400 seconds roughly make a day.
    14b * 17 X 10**-6 = 2.75 Days. Is it that pretty small? Our tidal height is over 1M!
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    Quote Originally Posted by sak
    14b * 17 X 10**-6 = 2.75 Days. Is it that pretty small? Our tidal height is over 1M!
    What are you calculating here? Is it the time shift within 14 billion years? The earth only exists for about 4.5 billion (10^9) years. I doubt that this rate can be extrapolated that far. It is probably only valid for a much shorter time.

    Anyway, what is that reference to the tidal height? Are you suggesting that the tides are created by the rotation of the Earth? I think, in that case you should better look it up somewhere, because they aren't. At least not that simple, depending on the point of view how to explain them.
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    The liquid core of earth is what keeps it at the speed it is going at, pretty much. It would go much faster if the core cooled off.

    My aunt Carole showed me the uncooked and the hardboiled egg spin test. Pretty cool.

    MY guess is that if there was not some liquid in the core they could probably go faster.



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    Quote Originally Posted by William McCormick
    The liquid core of earth is what keeps it at the speed it is going at, pretty much. It would go much faster if the core cooled off.

    My aunt Carole showed me the uncooked and the hardboiled egg spin test. Pretty cool.

    MY guess is that if there was not some liquid in the core they could probably go faster.
    Oh please. How would that be possible? It is just its inertia of rotation. The breaking is done by tidal breaking by the sun and the moon. Did you know that the core of the earth is made of an outer shell of liquid iron (mostly) and an inner solid core? This is the thought to be the earth's dynamo producing the terrestrial magnetic field.

    I suppose your aunt stirred the egg in water. This causes breaking due to friction. The test works, because the raw egg has a tendency to keep upright which is done by the chalaza (just looked the name up). You might remember the discussion about the main axes of inertia. The initially induced rotation is not done along one of the main axes. This hinders the rotation to continue.

    http://en.wikipedia.org/wiki/Egg_(food)
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    I think he (william) was talking about the test where you spin an egg and stop it with a finger and let go before the liquid yoke inside stops rotating, thus allowing the egg to resume spinning.

    Hard boiled eggs don't do this, it all has to do with inertia.

    But the thing that started the core spinning is as Dishmaster said:

    "It is a relic from the formation of our solar system....in the beginning everything in the universe has a slight rotation, how small it may be. This often a result of encounters of - let's say - gas clouds that attract each other by gravity."
    "It's no wonder that truth is stranger than fiction. Fiction has to make sense." - Mark Twain
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    Quote Originally Posted by Dishmaster
    Quote Originally Posted by William McCormick
    The liquid core of earth is what keeps it at the speed it is going at, pretty much. It would go much faster if the core cooled off.

    My aunt Carole showed me the uncooked and the hardboiled egg spin test. Pretty cool.

    MY guess is that if there was not some liquid in the core they could probably go faster.
    Oh please. How would that be possible? It is just its inertia of rotation. The breaking is done by tidal breaking by the sun and the moon. Did you know that the core of the earth is made of an outer shell of liquid iron (mostly) and an inner solid core? This is the thought to be the earth's dynamo producing the terrestrial magnetic field.

    I suppose your aunt stirred the egg in water. This causes breaking due to friction. The test works, because the raw egg has a tendency to keep upright which is done by the chalaza (just looked the name up). You might remember the discussion about the main axes of inertia. The initially induced rotation is not done along one of the main axes. This hinders the rotation to continue.

    http://en.wikipedia.org/wiki/Egg_(food)
    I would take the couple of minutes it takes to boil an egg. And spin both the raw and boiled egg before I went on about it. Just spin both on a table.

    I was amazed when I saw it. If someone put the question to me. I probably would have thought of liquid state change bombs. And tested it before answering.

    However when I saw the difference I could not believe it.

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    William McCormick
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    Forum Masters Degree SuperNatendo's Avatar
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    William, I can't make much sense out of this last post, whats all this about bombs?

    The unboiled egg spins because the liquid inside it is still spinning. Thats not what STARTED the egg spinning but what allowed it to start spinning again after it was 'stopped'.

    The planet started spinning as a result of the formation of the solar system.
    "It's no wonder that truth is stranger than fiction. Fiction has to make sense." - Mark Twain
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    Quote Originally Posted by SuperNatendo
    William, I can't make much sense out of this last post, whats all this about bombs?

    The unboiled egg spins because the liquid inside it is still spinning. Thats not what STARTED the egg spinning but what allowed it to start spinning again after it was 'stopped'.

    The planet started spinning as a result of the formation of the solar system.
    You need to go and do the egg test. You have shown that you did not do it.
    It is a fascinating real science demonstration that changes things. It demonstrates a million things.

    A liquid state change bomb, requires time to break the casing of the bomb. During this time of compression, a truly remarkable amount of energy is stored in the casing of the liquid state change bomb. So much pressure and friction is created, that it super heats to the temperature of the sun. And then it releases the energy.

    Some firemen are shown a demonstration that uses the idea of storing heat in an substance. Often 55 gallon steel drum containers can store massive amounts of pressure before blowing. If you put just a couple gallons of gasoline in one and heat it over a fire, over time.

    When it explodes the results often horrify those that witness it. They are forever unafraid of winning a revolution. And this is just a micro incident compared to the liquid state change bomb.

    Sincerely,


    William McCormick
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    And here comes again the lord of destruction. It's just disgusting. What is going on in this mind?
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  21. #20  
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    William, please state clearly, concisely, without equivocation exactly what the results of the egg test are. Please do so without meandering off with nonsense about bombs and revolutions and other irrelevancies.

    So we are clear on this, I am asking you to do this as a moderator. I expect compliance, otherwise further contributions by you to this thread are liable to be deleted without warning.

    Thank You
    Ophiolite
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    Quote Originally Posted by Ophiolite
    William, please state clearly, concisely, without equivocation exactly what the results of the egg test are. Please do so without meandering off with nonsense about bombs and revolutions and other irrelevancies.

    So we are clear on this, I am asking you to do this as a moderator. I expect compliance, otherwise further contributions by you to this thread are liable to be deleted without warning.

    Thank You
    Ophiolite
    Ok, I thought it better that they do the test, rather then rely on me, that they seem not to trust.

    If you spin a hard boiled egg, it spins well and persists for a rather long time. If you spin a raw egg, it will not get up to speed and just slows right down.

    I would keep both eggs at room temperature for the experiment. The results are better.

    The hard boiled egg can really spin fast. The raw egg cannot spin as fast or as long.



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    William McCormick
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    Quote Originally Posted by Dishmaster
    And here comes again the lord of destruction. It's just disgusting. What is going on in this mind?
    Those that fear destruction have not decided to be scientists yet.


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    William McCormick
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