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Spining and weight loss

  1. Nov 3, 2009 #1
    Wonder chick have a question again today.

    I heard from doucumentary that when object is spining, It's bit lighter than when it stop. My understand is because Weight distribute to orther vecter than going down to gravity.

    So, Is it possible that object can spin fast enough to Its weight become zero? (cut thing about that object gonna break and scatter around because g-force out)

    and another question just come to mind while I posting this topic.

    I know that we can't go faster than light speed due the relative theory, but what if object that spin as fast as light speed? is it same thing?

    **sorry for a lot question, It's kill my eyes and my brain to look at all old topic to find that there some other person ask the same thing before. (My glasses are thick enough already)**


    PS. English is not my native language, forgive if I wrong in gramma or wrong spelling.
  2. jcsd
  3. Nov 3, 2009 #2

    Doc Al

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    Do you have a specific reference? I know of no such effect.
  4. Nov 3, 2009 #3

    Andy Resnick

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    The OP (or the show) could be referring to the discredited Podletnikov 'experiments'
  5. Nov 3, 2009 #4

    Doc Al

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    That's what I suspect.
  6. Nov 3, 2009 #5
    I can't exactly recall the name of doucumentary, It's been arrange by tv program in my country.

    but it's about UFO thing and the way it fly.

    Why? Is it wrong? I didn't mean to discredit anyone
  7. Nov 3, 2009 #6


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    This means the reliability of the claims are nigh-zero.
  8. Nov 3, 2009 #7
    Something wrong here.

    The Matter is not "reliable or not" but it's "true or not".

    Sorry but I Ask as someone who doesn't know, didn't mean to oppose anyone. If what I believe is wrong so tell me.

    Fantasy is the most basic of all science theory right?


    So, If fast spining object become bit lighter than normal is not true than fine.
    but what about object that spin faster than light speed? what will happen?
  9. Nov 3, 2009 #8


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    I think the answer has been answered here as not true.

    What? No. Fantasy is pretty much an anathema to science.

    Objects cannot spin faster than the speed of light. As the object's rim approaches relativistic velocities, more and more energy will be required to spin it faster. Eventually, all the energy in the universe will not be enough to make it spin any faster.
  10. Nov 3, 2009 #9


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    Since there is no solid evidence that UFOs are alien spacecraft, obviously we couldn't know how they would fly!
  11. Nov 3, 2009 #10
    It's Impossible, Thank you, That's clear enough.

    But there's says ... When we observ something go fast almost at light speed the we'll see time of that object slower and it size is smaller, and when it reach light speed time stop and it will vanished because it mass become zero. (no body say's about about not enough energy or any other oppose fector)

    So, If round object like ball spin to light speed, It' will become like that too?

    I just want to know by cut some oppose fector out. I'm not sciencetist, just normal people who interested in.
  12. Nov 3, 2009 #11


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    It will be length-contracted in the direction of its movement, yes. i.e its circumference will decrease, though its radius will not.
    It will never reach light speed. Ever.

    However, as it approaches light speed, time in its frame of reference will dilate without limit as observed from an external frame of reference (to us it will appear to 'age' slower).

    And as it apporaches light speed, its mass will increase without limit.
  13. Nov 3, 2009 #12
    mass increase without limit? hmmm.... so it become almost like black hole than. (infinite mass, extremly gravity etc...)


    oh and one thing

    It's true that fantasy is more like anathema to science, I admit.
    But is it because people always fantasy to something so science born to make that fantasy become real? (or even bust that fantasy sometime)

    Like... people fantasy about fly in sky like bird and try everyway they can and finally Aerodinamic is born and make fantasy about flying become real?

    Fantasy and science are just different side fo same coin, opposing yet cannot separate.

    If people not fantasy about anything, science will never be born too.


    okay okay, I think that's enough.

    Thankyou for awnser all my Curious, your great Science Advisor.
  14. Nov 3, 2009 #13
    So for a ball spinning at a such (peripheral) speeds close to c, what would happen to its gravitational mass? If placed on a measuring scale, what weight would be recorded?
  15. Nov 3, 2009 #14


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    No. In its own frame of refernce, the object experiences no change in mass. Thus, no black hole.

    People wouldn't be much without both fantasy and science. That much I agree with.

    Keep asking. We loooove helping people.
  16. Nov 3, 2009 #15
    Not just science. Art forms also become dull without fantasy-unrestricted imagination. I feel imagination is one thing that distinguishes machines from a few life forms.
  17. Nov 3, 2009 #16
    A black hole is not one with infinite mass.
  18. Nov 3, 2009 #17


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    I think it's safe to say he was thinking that, if an object's mass increases without limit, it will at some point collapse into a black hole. While his supposition is true, it has nothing to do with relativistic mass increase.
  19. Nov 3, 2009 #18
    Than maybe just maybe, inside black hole itself, It don't even know that Itself are already collapse. It just wonder why everything are rushing into them.

    Like, inside frame of refernce they think they still a normal ball (no change in mass), but to the oursider it become black hole.

    funny huh...
  20. Nov 4, 2009 #19

    Vanadium 50

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    It's probably not a bad idea to remind people to look at the Overly Speculative Postings section of the guidelines. It's very difficult to discuss anything that's not grounded in facts.
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