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Taking off Technique Please Help

  1. Nov 28, 2005 #1
    How are you everybody in this forum !!
    i would like to know if it is possible to take off a small machine from the ground to fly away about 200 or 300 Kilo-grams using other technique rather than differing the pressure of air like the most all air-planes do.
    My idea was:
    -------------
    Is that possible in physical and mathematical points of view that i can take off an object from the ground to fly up using opposing force against gravity but this force will be calculated just to enable the object to fly up to a specific level high against gravity without using reactors and running in high speed to fly like normal plane or even without vans to be turned around to take the object off from the ground i mean other techniques rather than helicopters or air-planes techniques.
    To use a force against gravity with specific potential to fly the object up to specific level in air (From the physical and mathematical point of view).
     
  2. jcsd
  3. Nov 28, 2005 #2

    Danger

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    If you supply powerful enough opposing magnets you can get a levitation effect from the repulsion. It isn't really practical outside of the realm of mag-lev trains and such. Anything over a few inches of lift would be prohibitive from an energy standpoint, and there'd be nasty stability problems with something not restricted to some sort of rail or other guide system. There's no such thing as anti-gravity.
     
  4. Nov 28, 2005 #3

    russ_watters

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    Sound to me like you are asking if anti-gravity machines are possible (machines that directly cancel the force of gravity). They aren't.
     
  5. Dec 2, 2005 #4
    Can you guys prove that antigravity doesn't exist? If not, then why be so closed minded to it? I don't understand, don't you have to be openminded...expecially in such a field as physics? To be honest, I'm disappointed.
     
  6. Dec 2, 2005 #5

    berkeman

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    We *are* openminded. And smart about what we spend our time working on. If you spend a lot of time working on antigravity rays and perpetual motion machines instead of inventing inportant practical things like the X-ray machine, then you most likely not contribute much to physics and humanity.
     
  7. Dec 2, 2005 #6
    If you are open minded people then that must impy that you believe antigravity to be a possibility? And if it's a possibility than shouldn't antigravity be a research field...afterall, this is what research is about right? And I partially disagree with your statment berkeman. True, practical things like X-Ray machines are important and contribute to humanity. But on the other hand, discovering antigravity (if it exists) would have a much greater impact on humanity and definitely will have a much much deeper impact on Physics. By the way...Boeing worked on Antigravity for a while...so there are people out there who are giving there time researching into Antigravity..
     
  8. Dec 2, 2005 #7
    One more thing berkemann..what makes you so sure that antigravity relates to any "rays or perpetual motion machines"? I am familiar with this old topic of gyroscopes and antigravity waves matter..but what makes you so sure that any of these relate to antigravity?
     
  9. Dec 2, 2005 #8

    Art

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    Isn't there some theory based on the 'M' theory that gravity 'leaks' into our universe from a higher dimension? Proponents say that's why it is such a weak force as only a small amount of the full force reaches us the rest being spread around several other dimensions. The theory also negates the need for dark matter. If so isn't it possible that anti-gravity resides in this higher dimension also?

    Edit I found a link for the theory here - http://www.nyu.edu/fas/Research/200310_tradition.html
     
    Last edited: Dec 2, 2005
  10. Dec 2, 2005 #9

    G01

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    I refuse to get into discussions on Things like this usually because I DON'T KNOW ENOUGH ABOUT IT.

    Simple, did it ever occure to you that the reason these people aren't taking antigravity seriously because they know something about gravity that YOU DO NOT KNOW.

    There are some very intelligent people on this board and its really a privelege being exposed to them. So what I'm trying to say is that maybe they know something you don't about gravity that makes antigrav impossible. Learn from those more experienced than you. Im not being mean here. Just offering advice. There are some very intelligent people here. Learn from them. If the people here are not open to antigrav THERE IS A REASON FOR IT. They know something that makes them believe very strongly against it. Learn from them.
     
  11. Dec 2, 2005 #10
    How can I when the existence of antigravity remains a "possibility"? I can't just shut the subject off...one more thing G01. It's things that we don't know about that we research...don't just shut a subject out when it's still a possibility.
     
    Last edited: Dec 2, 2005
  12. Dec 2, 2005 #11

    G01

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    IMO the reason anti grav isn't considered is that all forms of matter and energy we know of exert the force of gravity. NO MATERIAL we know of exerts an anti gravitational force. If a material like that is every discovered then believe me it will be researched. This is just my opinion. Im no expert.
     
  13. Dec 2, 2005 #12
    Yes it's true what you are saying G01. But what about the so called "Dark Energy"? Doesn't it, exert an "anti gravitational force"? If it is then...the "material" you are referring to is already being researched into. I'm no expert as well...just a college student and a physics enthusiast in the process of learning physics.
     
    Last edited: Dec 2, 2005
  14. Dec 2, 2005 #13

    russ_watters

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    No, it doesn't. Being open minded means that you objectively evaluate all the evidence and come to a logical conclusion, without a preconceived bias for what that conclusion should be. Evidence shows that anti-gravity is likely not possible, so it is not reasonable to put effort into researching it.

    Don't take that to mean that future discoveries could change that, but scientists, like anyone else, play the odds: they want to contribute and the evidence says betting on anti-gravity isn't a good bet.
    Have you ever heard of Pascal's Wager?

    Also, fyi, anti-gravity and perpetual motion are related because the concepts violate some of the same laws of physics.

    Anyway, like G01 says - learn what is known about gravity, then revisit your question. You will likely find that you agree.
     
  15. Dec 2, 2005 #14
    No I haven't..care to emphasize who Pascal's Wager is?..and If what i mentioned isn't refered to as open minded..I would very much like to know what it's called so that I will not make a mistake in the future...Thanks And...yes "what is know about gravity"..i agree with this.
     
    Last edited: Dec 2, 2005
  16. Dec 2, 2005 #15

    G01

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    I don't know enough about that subject to answer. But i'd say that if dark energy is being reasearched, and it causes an anti gravitational effect, then anti gravity must be being reasearched along with it. I pretty sure that dark energy hasn't been proven to exist. Its a purely theoretical concept that is being worked on. The problem is that anti grav is on the fringe in the science world. Theres not enough theory or experiemental evidence to suggest that it exists. If there ever is then it'll be considered. But dark energy is only an idea as far as I know. If Im wrong someone please correct me.
     
  17. Dec 2, 2005 #16

    Danger

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    Art, I'm somewhat familiar with the 'leakage' theory of gravity. Keep in mind, however, that even if it turns out to be correct we have no way to access dimensions other than our own.
    As for the rest, all evidence so far indicates that antigravity is not a possibility despite our limited knowledge of gravity itself. If it consists entirely of a wave-like distortion of spacetime, there is no way to 'flatten' it out. If the graviton theory is even still being considered (?), then a graviton would be its own antiparticle the same as a photon.
     
  18. Dec 2, 2005 #17
    I don't know why everyone is debating the issues of anti-gravity. The Op never said anti-gravity that I can tell. He mearly said a force against gravity is used. Sounds like a rocket to me, unless that's what he means by no reactor? You could use a rail gun type setup to launch something into the air. Maybe I'm missing the point.

    Furthermore, if you launch a rocket that travels fast enough you should be able to maintain a low earth orbit, even in the atmosphere, given enough continuous thrust.
     
  19. Dec 2, 2005 #18

    Danger

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    Snouto indeed did not mention antigravity in his question. That's why I mentioned maglev as the only non-reaction lift mechanism that I could think of. When he ruled out props and rotors, I assume that he was including such mundane things as rockets.

    Given continuous thrust, as long as it exceeds weight and drag, you don't need any particular speed to maintain an orbit. A hovering helicopter is 'in orbit' in a way. The high speed requirement is for a ballistic orbit.
     
  20. Dec 2, 2005 #19

    russ_watters

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    Pascal's Wager is the idea of betting a tiny amount of money on a virtual guaranteed failure, but with the tiny possibility of a massive payoff. It's what motivates people to play the lottery (which I call "the idiot tax") and it's why companies like Lockheed and government organizations like NASA occasionally bet on near-certain failures. It's a logically flawed approach to both business and science, but starry-eyed dreamers will always do it.
    I'm not sure that there's really a name for it, but it's basically just the erroneous belief that anything really is possible. It's similar to gullibility, but that isn't quite it.
     
  21. Dec 2, 2005 #20
    THanks russ_watters. But I don't think physics is about "masive payoff". And yes..i see your point about gullibility, but I don't quite think you understand where i'm coming from. Do you dedicate your life to physics? If you do, then i'm perfectly fine with you saying this.
     
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