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Id appreciate feedback to develope an idea

  1. Jan 23, 2006 #1
    i have a flat box in which i put a spinning beam hold by the center

    i putweights on the beam that can run longitudinally on the beam so when the beam spins the centrifugal force send them away from the center

    i tight a cable to a corner of the box and the weights in such a way that when the weights are in the end of the beam, as it spins the cable tenses and pulls the weights to the center

    in this way the weights increase the radius during 3/4 of spin due to centrifugal force and decrease the radius during 1/4 of turn due to string tension

    what i expect is some thrust in the direction of the quarter of turn whes theres tension on the string
  2. jcsd
  3. Jan 24, 2006 #2
    I am not sure I have well understood your project.

    Best regards

  4. Jan 25, 2006 #3
    i can not attach the draw i made for being to big so i put it here:

    [crackpot forum url deleted]

    [Moderator note: There's no excuse for that. If you can't draw it simply and resize it to fit the attachment limit (just how BIG is this drawing anyway), then use one of the freebie image upload area and point the url to that. Citing a link to a crackpot forum is not allowed.]
    Last edited by a moderator: Jan 25, 2006
  5. Jan 25, 2006 #4


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    OK, so you've set a rod in circular motion inside your box, and you've got a brake on it. So, at some point the box will jerk rotationally. Yup. No problem.

    If you put some angular momentum into a system, you can reasonably expect to extract a small amount of it through some delayed mechanism. What's the big deal?

    Or are you thinking this is some sort of perpetual motion device?
  6. Jan 25, 2006 #5
    http://www.2and2.net/Uploads/Images/File1931.jpg [Broken]

    im in the top of a tower and two cannons are shot underneath me, one to the left and one to te right, im united to the cannonballs by a cable and i give away cable or take it with a spool lests look at the drawing:

    the cannonball i shot in trajectory 3, a straight one, i give away as much cable as needed so the tension of the cable is 0

    the tension in trajectory 1 the circular one the tension is constant of 10000 N so the tension is the same the one that pulls up that the one that pulls down

    but in the trajectory 2 the one that is first an outwards spiral and then and inwards one the tension that pulls down is of 1 N while the one that pulls up is of 10000 N

    i would be virtually shot up in trajectory 2 with almost no reaction or it being a virtual vector
    Last edited by a moderator: May 2, 2017
  7. Jan 25, 2006 #6
    the idea is to get a thrust engine that sends no mass away

    im not saying theres no reaction and of course you need energy to power it

    the reaction would be the same than a person who sits on a spinning chair and by spinning on his hands a wheel rotates the chair

    he doesnt rotate a mass on the oposite sense of the chair but theres still a reaction
  8. Jan 25, 2006 #7


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    Except the heat and gasses from the firing mechanism. Once you run out of fuel to fire your masses and retrieve them, you're dead in the water.

    And don't forget that to fire those masses forward, all your thrust will push your vehicle backward, thus no net gain.

    Consider: the masses exiting and returning result in zero-sum. Eliminate them. Point the cannon toward the rear, and you'll make better use of the escaping heat and gasses - you'll be converting them *directly* into movement.
  9. Jan 25, 2006 #8
    yes but imagine my drawing as an engine where the cannonballs are pistons

    it could work from solar energy so it could travel very far

    also remember that for the cannon that shoots forward theres another that shoots backwards so the horizontal component nulifies its only the vertical compnent of the tension the one to look at
  10. Jan 25, 2006 #9


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    You're still trying to use gadgetry to obfuscate the basic mechanisms involved. You put energy into the system initially (and now you're talking about powering it with solar power). What you'll get out of it is the work that can be done from these two sources. Everything else is merely a way of trying to store that energy. Your system is going to throw a whole lot of momentum around, all of which (not including the initial and solar energy) will net to zero.

    Why don't you just use it to power a flywheel? Same principle as what you're proposing (storing energy as angular momentum), but a flywheel is more efficient and much simpler.

    And yes, the vehicle will travel for a while. But you're still not getting out more than you put in.

    Proposal #2:

    If your goal is to get a vehicle to travel a long ways, frankly, you don't need a mechanism at all!

    You're allowing for frictionless parts, right? (Otherwise your idea falls flat, right?)

    So here's my nigh-perpetual motion device: three wheels on the bottom of a board. Give it some initial energy (just as in your proposal) - give it a push. With frictionless bearings and wheels, it will travel quite a distance - farther than your device.
  11. Jan 25, 2006 #10


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    If you push something forward in space, you go backwards.

    You're forgetting Newton's second law.

    This was a major problem on the very first spacewalk. One of the astronauts had to tighten a bolt (or something like that... twist a widget), but they forgot to give him footholds to hold himself steady. He was trying to twist the bolt, and hold onto the outside of the spacecraft to keep himself from spinning in the opposite direction. He gave up, exhausted, after 3 or 4 hours.
  12. Jan 27, 2006 #11
    my point is to make an engine that sends no mass away to accelerate

    this is regarded as imposible because of newton but then what happens with a gyro hanged on a string by its extreme, it will spin with precesion but no mass is spinned the oposite sense

    i think im really building this device

    i would need a string that winded by itself in a spool(with a spring) so the string doesnt mix up with the spinning wheel
  13. Jan 27, 2006 #12


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    Not that I'm trying to discourage you, I just am wondering if I'm missing what you feel you've discovered.

    "... an engine that sends no mass away to accelerate ... this is regarded as imposible because of newton ..."

    Not true.

    You are putting energy into the system when you initially spin up the gyro. Yes, you can get that energy to do work in the form of movement, at least until you use up you supply of energy.

    Am I missing something?
  14. Jan 27, 2006 #13


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    If you are intent on building it, I have some advice that will increase your likelihood of success:

    The gadget you've designed exploits some fundamental principle (say, perhaps, angular momentum) - what principle is, is currently unknown (I'm not saying you've discovered a new one, I'm just saying we haven't actually zeroed in on exactly where you're gainnig the energy from). But that principle has nothing to do with the details of your device, and everything to do with mass, force and movement. and that can be generalized.

    Your gadget is likely more complex than it needs to be in order to exploit the principle. The simpler your engine, the less can go wrong (in terms of loss through heat, friction and engineering challenges, etc.) So try to boil down your device to its most basic elements and work towards isolating that underlying principle. The closer your device gets to exploiting the principle directly, the more efficent its conversion to useful work.

    For example, if the principle works in a gadget that uses the energy stored in spinning mass, it should work on, say, a gyroscope, if it were designed the right way. It is way easier to get a gyroscope going without loss due to heat or friction or engineering challenges than your use of cannon and cannonballs.

    It also means you can solve the whole thing on paper, where things don't break or get stuck or operate poorly. If you try to build it, you will get bogged down in engineering issues rather than principles of physics.
    Last edited: Jan 27, 2006
  15. Jan 27, 2006 #14


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    In this, and also in previous threads that you have started, you were given plenty of advice to look into elementary intro physics text to get you off this over-unity "experiments" that you keep coming up.

    For example, your "example" of the gyroscope here is a clear indication that you have not understood basic Newton's laws. A gyroscope already spinning is equivalent to a mass already moving with no net force acting on it. This means that it will continue to spin, the same way the mass will continue to move, until a net torque or force acts on it. THere is no need for either of them to give off mass. There's no "propulsion" needed.

    However, when you CHANGE something, or have to work against a force, THEN you need propulsion. A rocket has to keep on ejecting mass in the form of gas because it either needs to accelerate the rocket, or to do work against gravity! If you have a gyroscope that isn't already spinning, you have to put a TORQUE onto the gyroscope to make it start spinning and pick up angular speed. This is where you either need something external, or the object has to eject mass to cause a momentum, or angular momentum change.

    Again, you have been given ample leeway here in presenting your question. Each one of them keeps coming back to the SAME thing, and the same basic physics principles. There is only so much that this forum can do before you yourself have to put in your own effort in learning these things. After more than several months since you first got here (in your various other incarnations), haven't you noticed that there has been NO progress at all in your understanding?

  16. Jan 28, 2006 #15
    zapperz im studying and i believe most of what i study but though i have no right to express it here i have the right to believe that actual science is a matrix to keep the world away from a revolution

    for example i cant discuss here that i raised the center of gravity slightly by use of gravity by using a balance, i choose to believe my eyes before books, i suppose you think im dislearning XD

    the set up about i ask now is this:

    i have a spinning beam hold on its center and two weights can move longitudinally along the beam

    when vertical both weights are at distance of 20 cm but when horizontal one is at 10 cm and the other is at 30 cm

    angular momentum is conserved as a whole but i want to test if some artificial gravity appears similar to the one of 2002 rotational ship
  17. Jan 28, 2006 #16
    in fact if some thrust appeared maybe electrons in atoms follow the pattern i draw creating an aceleration in a fixed direction by every single atom

    that would explain than an atom of h2 falls at the same rate than an atom of plumb, for every electron propelling theres a proton to be propelled so the ratio weight-thrust is always kept constant
  18. Jan 28, 2006 #17


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    Damn this is gooooood readin' here. That made me laugh. I am anxiously awaiting a response to this one.

    So you raised something by using a lever? Oh, but gravity was pulling the one end down which brought the other end up? So how did gravity pull down the other side? Did you have to put a weight on that side?
  19. Jan 28, 2006 #18
    no what i did is buid a balance with the center of gravity and the spinning axe in the same position( i made sure of this by turning it upside down)

    then i added a vertical cigarrete in the axe as the fiel rising the center of gravity slightly and the balance would still work

    from a 45º position it would go to horizontal what means that gravity raised slightly the COG

    of course once the balance levels this potential energy is spent

    but i have made at least one experiment obtaining results opposite of those expected by mainstream
  20. Jan 28, 2006 #19


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    I think the point is that all of this information is available to you in basic physics books. Once you study up on it, you'll find your own questions answered.

    And that way, if you choose not to believe what the books say (like you choose not to believe what forum members are telling you) - well, the only time wasted will be your own.
  21. Jan 28, 2006 #20


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    I am no physics expert. Being just a student myself I am still learning, but I BELIEVE, and maybe someone farther along in their physics education can confirm or deny this, but I believe that this change in height of the balance changed because you spinned theaxe in a way that the momentum vector pointed straight upward and the axe was sitting on an incline and began to tilt. As it tilted, the momentum vector "wanted" to stay pointing straight upward and "pulled" the axe off of the balance a little and the balance went back to horizontal as the axe was "pulled" off it and at horizantal the axe"s momentum vector is pointing straight upward and with less tendancy to change so the vector stopped "pulling" up any higher, but pulled enough to keep it there. (Until the axe stopped spinning of course)

    I really am not sure about this. Please someone confirm this for me. It sounds much more plausible than anti gravity

    Eosphorus, I commend your yearning to discover something new. Any true scientific mind wants to discover new things. You never hear a scientist say, "I never want to discover anything new in my career."
    Your problem is that you need to know what is already known. Before making a new theory of antigravity, make sure that this phenominon isn't alreadyexplained bya much simpler theory. Good luck to you in you studies.
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