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09-08-05, 12:20 AM #381
MacM:
Perhaps you can explain how a rocket can accelerate to a speed greater than the speed of its exhaust gases.
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09-08-05, 12:30 AM #382The reaction of a rocket is based on F=ma. That function is derived from aboard the rocket itself. That is the thrust engine views the rocket at relative rest. Hence F = ma doesn't change.
Originally Posted by James R
You are taking the view that the rocket exhaust is pushing againt it's own gas column. That would not be a useful design.
Remember I have designed and built inertial drive systems which use no exhaust. All thrust is internal.
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09-08-05, 01:06 AM #383If it doesn't push against its gas column, what does it push against? Anything? (Assuming it is in space.)You are taking the view that the rocket exhaust is pushing againt it's own gas column.
And they didn't give you the Nobel Prize.Remember I have designed and built inertial drive systems which use no exhaust. All thrust is internal.
You've achieved the impossible - action without reaction. How interesting.
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09-08-05, 02:42 AM #384Are you really a physicist? Can't be. Do I need to explain F = ma and action and equal reaction?
Originally Posted by James R
Who knows they might yet.And they didn't give you the Nobel Prize.
If you think talking stupid is appropriate here then I can talk stupid as well.
Are you always so ill informed, confused, in error? You would of course be also talking about:You've achieved the impossible - action without reaction. How interesting.
http://www.sandia.gov/media/imbalance.htm
Which is one model I built some 20+ years before them. In the technical write up (which they provided me) they specifically discuss using this to change orbits. Now just what did they push against. And what have my several different models pushed against?
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09-08-05, 02:56 AM #385Action = rocket goes forward. What is the reaction, in this case, according to you?Do I need to explain F = ma and action and equal reaction?
This works by moving masses around within a spaceship. The masses and the spaceship are in contact, so they push against each other. The total momentum of the system does not change.Now just what did they push against.
This is not an "inertialess drive".
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09-08-05, 07:41 PM #386Registered Senior Member
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The question is moot because no one giving the problem two cycles of thought will ask it.
Originally Posted by MacM
Your analogy doesn't fit. The particle is always at a velocity less than the wave front.Can a sail boat with it's sail orthogonal to the wind reach the speed of the wind?
Of course not. To accelerate the boat there must be a delta p across the sail. As the sail boat approaches the speed of the wind the delta p decreases and acceleration decreases. At the speed of the wind there is no delta p to accelerate it any faster.
Guess what under those conditions it does not matter how large your sail is you cannot accelerate the boat. Gee infinite wind energy cannot accelerate the boat. Must be that the boats mass has increased to infinity.
We are talking about the absorption and emission of energy in both cases.Two different physical principles. Why would you think they are related.?
Other stuff:
All "thrust" requires "exhaust". Now the use of the terms "thrust" and "exhaust" are semantical, and doesn't change the underlying principles. A closed system will never produce "thrust", energy must leave or enter the system. This may create an imbalance of energies so "thrust" is generated.
In the case of MacM's link, no new energy is entering or leaving the system, so no new "thrust" is generated. It is a redirection of existing "thrust".Last edited by Raphael; 09-08-05 at 08:11 PM.
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09-08-05, 08:55 PM #387Registered Senior Member
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How is the "thrust" internal?
Originally Posted by MacM
Yes you do need to explain. You said all the thrust was internal, so how does this get you anywhere given action and reaction? Is all the thrust absorbed in the way a turbofan jet engine uses a turbine to absorb some of the exaust and spin the fan?
Originally Posted by MacM
Where might I find these different models?
Originally Posted by MacM
Last edited by Aer; 09-08-05 at 09:09 PM.
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09-08-05, 09:21 PM #388Moderator of B&E forum
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Thanks for the faint prase. I gave the second explanation also many posts ago in another thread, but included something I later had slight doubts about (please give me your view, as if it is correct as I think it is I will resume giving both ways of thinking why we have two tides instead of just one.).
Originally Posted by James R
I said that the "far side" tide was more due to the fact that that ocean had to orbit the common Earth/Moon center of mass also, but that it had too little force acting on it to produce the reqired acceleration. Thus it was elevated above the level that centrifical and gravitational forces would give it to add gravitational energy to the shape of the ocean. This energy can be lowered in a virtual displacement - hence there is suplimental force acting on the "raised" water to supply the force that is "missing" and these combined forces are just what is required to keep the far-side ocean orbiting with the solid Earth around the common C.of M.
I still think there is something to this, but am unconfortble with my words. The real problem (for me) is why does the far side ocean orbit the C.of M.? It is very clear to me that it must and does but by moving away from the center of the Earth it is moving into a weaker gravity field. When I notice this, I tend to think there should be a "depression" tide on the far side to supply the compensating force for the weaker moon's gravity by putting that water in a stronger Earth's gravity field. - I need a little help the true understand of the second view - so I stopped giving it.
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09-08-05, 09:40 PM #389Moderator of B&E forum
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Obviously you have little sailing experience. The speed of the wind relative to the sail on a fast moving boat is not orthogonal - it is producing lots of "lift," like an airplane wing because the speed of the air moving over the sail (wing) is greater than the wind's ground speed. For example if boat and orthogonal wind speeds are both 10knots, then roughly speaking the wind speed over the sail is 14knots.
Originally Posted by MacM
Sailing with the wind "orthogonal" is called "on a broad reach"
Sailing with the wind at the stern is "running with the wind."
When you are "running with the wind", your speed will be less than that of the wind, but on a "broad reach", it can be significantly higher. (There are other factors, the most important is whether you are a displacment boat or "plaining")
Displacement boats can not go faster that the speed of the wave whose half wave length is approximately the water line length of the boat. (Why big displacement boats can go faster than small one - water waves have dispersion.) Effectively your boat has dug a hole in the ocean and is trapped in it.
If you are on a plainning boat what limits your speed (It will always be less that the vector sum of your and the winds speed also, but that is always greater than the wind speed.) is mainly the friction with the water.
Now that you know all about sailing, cast off, but make sure the boat has a weather helm - that is important for us old guys or young one that drink too much. (boat should automatic turn into the wind if you pass out, not sail on towards europe.)Last edited by Billy T; 09-08-05 at 10:27 PM.
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09-08-05, 09:53 PM #390Registered Senior Member
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Ahh, thanks Billy T - I thought something was wrong with the example MacM gave and just couldn't put my finger on it
Originally Posted by Billy T
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09-08-05, 10:06 PM #391First I am not obligated to give you a correct scientific proof of principle. I am well aware of the current thinking regarding Newtons laws of action and reaction.
Originally Posted by James R
However, I do believe that definition is flawed and does not properly consider the affects of F = ma and centrifugal force which happen to lie at 90 degrees in cases of rotary motion and while directly related cannot and do not function in the equal and opposite manner of Newton's law.
Secondly, even if it were not for this fact, my own research (extensive BTW, perhaps $20,000.00 into several units. One weighing 100 pounds that not only powered itself in both directions on a rail bed but generated 12 pounds steady pull on an anchored spring scale) into these devices and what I have seen and recorded is in direct contrast to your assertion (or impliction here) that such devices do not work. They do. So it is your concept of physics that is in error. Not the concept of inertial drives.
Perhaps momentum does not change but the net directed momentum does propel inertial drive units. They function on thrust from F = ma and centrifugal force. Momentum is conserved in F = ma, acceleration and decelleration forces.This works by moving masses around within a spaceship. The masses and the spaceship are in contact, so they push against each other. The total momentum of the system does not change.
Sorry, I couldn't find this word in Webster.This is not an "inertialess drive".
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09-08-05, 10:17 PM #392Moderator of B&E forum
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Please post the section about changing orbits. I looked at the reference. Note that it is an attitude control system, used during reentry to change the lift characteristics of the re-entering satellite. They could due this with fins (little wings) etc but they would need to be quite strong and might burn off, so it is better to change attitude purely internally.
Originally Posted by MacM
More than 20 years ago, I think it must be around 35 now APL where I worked was building interal devices we called "momentum wheels" with three orthogonal wheels, we could orient the satellite any way we liked. As you torque up one, the satellite rotates the other way around that momentum wheel's axis (conserving total angular momentum - hence the name). When Satellite has almost turned to where you want it to point, you reverse the torque applied to the wheel and there you are with a new "attitude" - Perhaps you did not recognize what your reference was doing as this is a specalized, technical (and some what strange) word to use for orientation control - Read the article again and you will see they describe their system as "attitude control system". The only mystery to me is why is this 35 year old technology news worthy? We did not apply magnetic hystereous rods for both "zero energy" and "zero mass" required "attitued control" in "gravity gradient" satellites until 20 years ago - I look forward to reading about that system in another 15 years also. ( the reference's and our momentum wheels both required energy, but at least not the expenditure of mass the tangential "micro thrusters" used, which they replaced.)
Momentum wheels can be quite small and light weight if you have time to wait or only want to make fine continuous adjustements. Perhaps one could even use their computer's hard drive? You would need to assume the correct "attitude" with in the space craft but as Aer points out in later post (this is by edit) attitude = orientation control and among a bunch of men who knows what happens on a long trip?
There is nothing you can do along these lines to "change orbits" so again please post that section for all to read about a violation of physics.Last edited by Billy T; 09-08-05 at 10:51 PM.
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09-08-05, 10:21 PM #393Moderator of B&E forum
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To MacM - I intend this as friendly advice:
Don't expose your ignorance about sail boats & and momentum wheels - they are practical devices a lot of people know about. Stick to uniKEF.Last edited by Billy T; 09-08-05 at 10:37 PM.
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09-08-05, 10:21 PM #394Registered Senior Member
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So the only behaviour it is controlling is sexual behaviour?
Originally Posted by Billy T
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09-08-05, 10:38 PM #395Moderator of B&E forum
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That is a gay interpertation.
Originally Posted by Aer
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09-08-05, 10:54 PM #396Not a very sound reply. You are simply incorrect.
Originally Posted by Raphael
Doesn't fit. That is precisely the point. It is not possible to accelerate the particle faster than the propelling field. Since it has a finite velocity it is obvious why no amount jof power can reach or esceed theat veloicty. Mass change has no meaning in such understanding. It is energy transfer efficiency, not mass change that limits veloicty.Your analogy doesn't fit. The particle is always at a velocity less than the wave front.
Trying to disguise different physical principles by some dommon definiton isn't physics.We are talking about the absorption and emission of energy in both cases.
You have proven you don't know what you are talking about. Not only have I built a number of different designs, mechanical, electro-mechanical, fluid, magnetic, etc and they work but:Other stuff:
All "thrust" requires "exhaust". Now the use of the terms "thrust" and "exhaust" are semantical, and doesn't change the underlying principles. A closed system will never produce "thrust", energy must leave or enter the system. This may create an imbalance of energies so "thrust" is generated.
In the case of MacM's link, no new energy is entering or leaving the system, so no new "thrust" is generated. It is a redirection of existing "thrust".
Once differential forces are generated, which moves the frame, the frames motion imbalances the torque and requires power. So input power moves the system and system motion increases the power demand. You are incorrect in your physical analysis.
Guaranteed from first hand knowledge. Supported by virtue that Sandia (no crackpot outfit) indicated how the device could be used to change orbit in space.
Don't pretend to know things you do not based on some limited education in physics. (I don't mean this in any demeaning manner) but factually conventional physics and thoughts are not totally valid. Until you understand that you will not understand certain principles.
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09-08-05, 10:58 PM #397When this news came out I contacted them and had some lengthy discussion. I described the unit I had built 20+ years before, which much more simple and crude used the same physics principles.
Originally Posted by Billy T
They forwarded me a copy (10 pages) of technical data. It was in that data.
I no longer have those documents but forwarded them to my eldest sons that has taken over the research (6) years ago after I had a TIA (mini-stroke) and closed my research corporation.
I'll see if I can get them back or get another copy and post it if I can.
In this material they refer to it as a "Bang-Bang" unit. They stated that repeated cycling creates a directional thrust (which I also know it does having built and tested these devices myself.
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09-08-05, 11:07 PM #398Let me give you some friendly advice don't be so confident you know it all. Your suggestion is in violation of first hand knowledge by myself and is in contridiction with achievments of others.
Originally Posted by Billy T
Now that you have made a derogatary comment regarding my ignorance about sail boats, I suggest you support that assertion with some facts.
Therefore please post here exactly how you jpropose that a sail boat will ever reach, much less exceed, the velocity of the propelling wind when (AS I STATED) the wind is orthogonal to the sail and the boat aligned with the wind.
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09-08-05, 11:14 PM #399Moderator of B&E forum
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I did this already: It is the vetor sum of wind and boat speed, (which is always greater than wind speed alone) that the sail "feels." I even gave numerical example (in a 10 knot wind, a boat moving at 10 knots has 14 knots across the sail)
Originally Posted by MacM
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09-08-05, 11:19 PM #400Thrust being interanl simply means it is direct to the frame of the ship and there is no exhaust from the system as in a rocket or a skate board where you are throwing brick behind you.
Originally Posted by Aer
YOu can't and won't since they are still proprietary and under development. However, the one unit which has become public built by Sandia Labs, is physically simular the one I had built many years before.Where might I find these different models?
I had taken two car starter solenoids, one slug, and mounted them face to face on a plate attached to a shaft with a commutator. The were mounted so that as the shaft rotated centrifugal force slung the slug to one side creating centrifugal force over that 180 degree rotation whereafter the commutator then caused the magnets to yank the slug (at 90 degrees to the average Cf angle) to the opposite side and repeate it's cycle.
That is the unit produces centrifugal only over 180 degrees and the F = ma to cause that affect is in a fixed vector that is 90 degrees from the average centrifugal force vector. The net thrust vector therefore becomes forty five degrees (or halfway between Cf and F = ma) components.
If the frame moves it shifts the F = ma vector and reduces the Cf created, hence requiring input power to move the frame. The faster the acceleration of the frame the more power that is required.

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