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Thread: could merlin make magic and create momentum?

  1. #1 could merlin make magic and create momentum? 
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    merlin makes a spell to teleport himself and two circled stones to space, he also makes a spell to turn himslef weightless

    he starts in "one" counterrotating both stones very fast over his head

    he put the arms in cross as in "two" and voila momentum has been created

    whats wrong about this?


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  3. #2  
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    magic.


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  4. #3  
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    Merlin can't create a damn thing much less momentum , momemtum is always there for the taking!
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  5. #4  
    Reptile Dysfunction drowsy turtle's Avatar
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    Conservation of momentum has been violated.

    Conservation of energy has been violated.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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  6. #5  
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    Ignoring everything about magic and teleportation and weightlessness and such:

    If Merlin did all that, he would be adding momentum to the stones when he started rotating them (total momentum would still remain the same, but it would increase for the individual stones). If he moves to the cross position, what he is actually doing is moving the stones apart, while his weightless body moves up to between the stones, again not changing total momentum.

    unless Merlin also has a spell to magically increase momentum of course
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  7. #6  
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    no no notice that when the stones are above his head they are counterotating but once he puts his arms in cross both stones have identical sense of rotation
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  8. #7  
    Forum Professor sunshinewarrior's Avatar
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    Quote Originally Posted by luxtpm
    no no notice that when the stones are above his head they are counterotating but once he puts his arms in cross both stones have identical sense of rotation
    If that's the case, unless he has something to stand on, he will simply rotate in the other direction to counter-balance their rotation (it's why helicopters generally need tail planes - toherwise they would simply rotate counter to the rotor and not generate any lift). No momentum would be created.
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  9. #8  
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    thats why i said merlin is weightless

    if you dont like it imagine merlin as a flexible 1 microgram tube
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  10. #9  
    Administrator KALSTER's Avatar
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    He would somehow have to transform the angular momentum he induced in the stones into linear momentum on himself. The stones would stop rotating. I don't quite see how the stones being rotated either in the same direction or not would do anything useful.

    A similar setup would be if he magically rotated a wheel connected to a catapult via a spring-loaded system. Once he stops rotating it and releases the stop of the catapult, the spring-loaded system would release its potential energy into the catapult and propel him. If efficiency was 100%, then the travelling Merlin would possess the same extra energy as the spring-loaded system did before release.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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  11. #10  
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    Ah, so Merlin is turning the stones while they are turning around another axis.

    In that case, you are forgetting the gyroscopic effect. The stones will start turning around the third axis until they are both spinning in the plane of the drawing you made, again resulting in no resulting momentum.
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  12. #11 Re: could merlin make magic and create momentum? 
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    Quote Originally Posted by luxtpm
    whats wrong about this?

    that picture for starters...



    merlin was MAGIC, he didn't need to follow the rules of physics, he just thought, and it was so. in fact. HE invented GOD
    It's not how many questions you ask, but the answers you get - Booms

    This is the Acadamy of Science! we don't need to 'prove' anything!
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