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fleep

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Atmospheric pressure and its effect
« Reply #100 on: 08/06/2007 15:13:37 »
Hi BC;

Thanks for responding.


Quote from my messg to you:
"Rule 1 – All released objects in open space vacuum or in natural atmosphere, must free-fall.
Rule 2 - Loose objects in a sealed ship's atmosphere in space, must float in the air.

Sorry, but I dispute rule 2.
The things inside a ship that seem to be floating are in fact, in free fall
It's just that , etc.

You can not deny that they are physically suspended in the air in their ship because they contact no walls or floor (without effort.) The “circumstance” of their floating is certainly during free-fall, but the fact is that they will float in the air, and it only happens naturally inside a ship that is in open space, where objects are surrounded by a pressurized atmosphere. (Don’t bring up parabolic simulations. We both know that these have nothing to do with the reality of the content of my rules.) The evidence I am stating is FACT, which, as it’s stated, is indisputable.
The cause, and the reason for the scenario related to that cause are two different things. My Rule 2 sentence is accurate but I will change it for you.

You would not say that they “float” in the vacuum if they were outside the ship, because words have specific meanings. “Float” means: “Rest, drift on surface of liquid; hover before eye or mind, etc. I will use “hover” and “float” to clarify my rule.


Rule 1 says everything in the earth's atmosphere falls. I hold that everything outside it falls too. Your rule 2 reflects the fact that ships are usually in orbit.
That means that everything whether it's in a ship, a vacuum or the atmosphere falls.
That's also the principle of universal gravitation. Everything falls.

Weight is everything. Weight falls. Call it “gravitation” if you like. You know my theory says that weight and gravity are the same thing that go by 2 different names, except you say gravity attracts, and I say it doesn’t. Weight does not attract, unless a weight happens to be a magnet, (and of course, if the poles are opposites.)

By one interpretation of “free-fall”, some might actually surmise that if I drop a paper box with a lead weight in the bottom of it out of an airplane in absolutely still air that the lead weight will float in the air in the box. It will not float or hover in the air, but will have encountered a circumstance where its weight can only be expressed to the bottom of the box, since its weight will be increasing the speed of the fall of a light-weight box, thereby overcoming some of its air resistance. They are both falling, but the circumstance has changed the falling behaviour of the box. If they tip over and the lead falls out, the lead will beat the box to the ground. This is a circumstance-related event, just as is the objects hovering in the shuttle out in space.
The defined circumstance would have to be stated in my rule if the rule had to explain everything. Newton’s 3rd Law doesn’t explain “why”. My rules don’t have to explain why either.
My rules do not express “cause” at all, and they never did. Only my theory expresses what I interpret to be the reason WHY objects hover in the ship. That remains a part of my theory.

Re Rule 1 – It must be remembered that an atmospheric mass inside a ship is an “object” too. Yes, it free-falls as an object, as does the atmospheric mass and the objects and people in that mass.

(Not revised): Rule 1 – All released objects in open space vacuum or in natural atmosphere, must free-fall.”

(Revised): Rule 2 - Loose objects in a sealed ship's atmosphere in space, must float or hover in the air.

We can agree to disagree on the actual cause of the hovering, which I contend, as you know, that the atmospheric mass is a “blind pressure”, which is unable to provide  directional instructions to exert floating objects against any wall or floor of the ship.

Now. What is your answer to my question about the incongruence between Newton’s 1st Law of Motion, and his Law of gravitation? I already know what they each say and mean. Please tell me what’s wrong with my question.

Thanks

fleep


P.S. - Rather than guess, I'd like to see what would happen if a helium-filled balloon was released inside the shuttle. (It too would be free-falling, inside a mass - the pressurized atmosphere, inside another mass - the ship).
 

Offline Batroost

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Atmospheric pressure and its effect
« Reply #101 on: 08/06/2007 16:15:09 »
Fleep,

Two thoughts:

(1) You seem to be ignoring the full expression of Newton's first Law i.e. An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

The bit I've highlighted in Red is the bit that shows why there is no contradiction between this law and that for Gravity (at least as Newton understood it), as the gravitational attraction provides the unbalanced force necessary to accelerate the two bodies towards each other.

(2) Your Rule 2 bothers me because it seems incomplete. Imagine this, sealed spacecraft, floating spanner etc... At this stage either explanation - yours or Newton's explains what we see. Now the engine comes on. What do we see? To an observer inside the spacecraft there has been no change in air pressure - still the same in every direction BUT the spanner now seems to be accelerating towards the back! It is not floating it is visibly falling....!

Has the back wall of the spacecraft somehow become attractive to the spanner? Are we misinterpreting our measurements of air pressure? The answer is of course 'No' to both questions. The spanner only appeared to be floating because it was moving with the ship. As soon as the ship begins to accelerate the spanner will seem (to an inside observer) to have developed an opposite acceleration.

In physical terms, before the engines are turned-on both the ship and the spanner and any observer within the ship were in 'free-fall' i.e. there was no accelerating force acting on one without also acting equally on the other. This would be true if the ship were in deep space or if it was in a tight orbit around a planet.

Where our explanations diverge is what happens as the ship is braked by the atmosphere. It has to slow down by (as you say) >10,000 miles/hour and this requires the ship to experience an 'unbalanced force' - hardly surprising things start to 'fall' straight away within the ship. Once the ship has fully decelerated to terminal velocity within the atmosphere - with or without the aid of parachutes; this just affects how high the terminal velocity is - we conclude (in Newtonian terms) that the gravitational accelerating force on the ship is balanced by the decelerating force of atmospheric drag. At this point the net force on the ship is zero and it will fall at constant velocity. BUT the net force on anything dropped inside the ship is not zero - as it doesn't experience the atmospheric drag from outside - and it will accelerate towards the ground (which may or may not be the floor of the ship!) at the usual rate.

This is a self-consistent model of events. There are no discontinuities or contradictions between Newton's laws in any of this. A different model is not excluded but neither does it appear to be necessary?

Of course the model can be refined by replacing Newton's Laws with their relativistic equivalents, and by tweaking the forces to adjust for altitude but these are only, second-order effects.

Best wishes,

As Always,

Batroost


 

fleep

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Atmospheric pressure and its effect
« Reply #102 on: 08/06/2007 19:36:22 »
Hi Batroost;

First, an excerpt from Wiki.
http://en.wikipedia.org/wiki/Inertia#Theory_of_impetus

"Another profound, perhaps the most well-known, conclusion of the theory of Special Relativity was that energy and mass are not separate things, but are, in fact, interchangeable. This new relationship, however, also carried with it new implications for the concept of inertia. The logical conclusion of Special Relativity was that if mass exhibits the principle of inertia, then inertia must also apply to energy as well. This theory, and subsequent experiments confirming some of its conclusions, have also served to radically expand the definition of inertia in some contexts to apply to a much wider context including energy as well as matter.


You said:
You seem to be ignoring the full expression of Newton's first Law i.e. An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

The bit I've highlighted is the bit that shows why there is no contradiction between this law and that for Gravity (at least as Newton understood it), as the gravitational attraction provides the unbalanced force necessary to accelerate the two bodies towards each other.


There is no “gravitational attraction” at work here. It does not “provide” anything.

You said:
Now the engine comes on. To an observer inside the spacecraft there has been no change in air pressure - still the same in every direction BUT the spanner now seems to be accelerating towards the back! It is not floating it is visibly falling....!

No, it is visibly accelerating from a rest position, because its inertia has been broken. Newton’s 1st Law is at work.

I don’t think I said anywhere that inertia will not be affected in the sealed ship, by the application of an external force. The “appearance of flotation” that is often spoken of is real flotation, in the definitive sense. Are the things that are strapped down only “appearing” to be strapped down? When the engine fires, Newton’s First Law of Motion kicks in. Inertia is “broken”, and the engine’s force acts upon a spanner, or other floating objects, making them accelerate from no matter where they are in the ship.

The ship’s “blind pressure” is also a “brainless pressure”. Law 1 says, “go”, and the object goes in the direction opposite to where the ship is headed when the engine fires. There is no “gravitational attraction” needed to supply an unbalanced force. The ship's air pressure doesn’t know or care. When the engine shuts down, the spanner just resumes its blind, mindless floating. It doesn’t go back to where it was in the air, or stay “attracted” to anything. It “knows no responsibilities”. The atmospheric mass is blindly falling, and so is everything inside it, but these things are truly (and definitively) floating, as an effect of the blind pressure. IF the atmospheric pressure had any effect on anything in the ship, everything would be going ”somewhere”, but no floating thing has a job to do, because the pressure does not assign any “jobs”.

The instant departure from inertia is what foments acceleration of a “resting mass” in what might appear to some, as a Newtonian notion of “acceleration due to attraction”.

The point is this: No “thing” in the ship “knows” that the ship is in free-fall. An object can be said to be “at rest”, even while floating in the air. If it’s moving a bit, it’s probably due to light air currents created by internal systems and people moving around it that call up Newton’s 1st Law. Nothing gets “attracted” to anything; (any magnetism is excepted of course).

External forces on the ship will create internal effects over which the pressurized atmosphere has no say. It only matters whether the ship is in space, or in the atmosphere of the Earth. The same internal pressure that had one effect out in the vacuum, is now subject to a completely different effect when it enters Earth’s atmosphere. The ship is falling through a vacuum, and then it is falling through an atmosphere. The ship’s internal effects “environment” has changed, but the pressure doesn’t know that either. The vacuum and our atmosphere both “know their roles.”

The mere fact that there are air currents inside a sealed ship is evidence that the atmospheric pressure is, (as a force), a “benign factor”. If it had directed applications, (as in hydraulic cylinders), it might not be available everywhere in the ship when a breath was taken. The preparation of a global and constant air supply would be an incredibly difficult system to construct in a ship, if the pressure worked under assigned directions, as in hydraulics.

All of the exceptions that are taken to my theory about “blind pressure” are accredited to observation by onlookers. What “seems to be”, really is happening in the air, inside the shuttle. “Falling” is simply not a reason why the interior events are different when falling in a vacuum, from falling through an atmosphere. Falling is simply falling, and only this difference between circumstances can set and exhibit the variations.

That’s the explanation that funds my theory.

Best wishes, and thanks for getting back into the discussion. (You had me worried.)

fleep
 

Offline Batroost

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Atmospheric pressure and its effect
« Reply #103 on: 08/06/2007 22:50:53 »
Fleep,

Sorry I've read through that three times and can't say I'm any closer to understanding what you are getting at here.

Quote
There is no “gravitational attraction” at work here. It does not “provide” anything.

To be cheeky - what it provides is an explanation.... ;D

More seriously, the point about the spanner is that, by virtue of inertia, it only appears to accelerate backwards. It's inertia/momentum or whatever else you want to call it is unaffected because it has had no accelerating force acting upon it. It is the ship, and the observer that are accelerating forwards BUT to the observer the effect is indistinguishable from a gravitational acceleration (a manifestation of the principle of equivalence).

The trick here, once you realise that what you are seeing is simply a consequence of relative frames of reference is to realise that this is sufficient on its own to explain everything that is observed both in free-fall and in re-entry to the Earth's . Every example that you, I and BC have quoted fit the same model.

So, please (sorry!) can you try again to explain where you think Newton's First Law of Motion is inconsistent with his law of gravitation?

Quote
mass exhibits the principle of inertia, then inertia must also apply to energy as well.

Incidentally, and this is very much an aside, whilst energy and mass have an equivalency in relativity, the scaling factor (c2) is so very large that these effects aren't seen in everyday mechanics. For example, calculate the energy you'd have to add to a bucket of water to make it measureably heavier (i.e. increase its inertia):- for 5 kg of water (at 20 degrees), to add 1g would need enough energy to boil the water into steam 10 million times over!  So I don't see that this is going to be relevent unless I've missed something?

Best wishes,

Batroost

 

Offline rosy

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Atmospheric pressure and its effect
« Reply #104 on: 08/06/2007 23:31:03 »
I daresay this has been addressed already but how are you getting around the "feather in a bell jar" experiment which shows that not only does (say) a ball bearing fall in a vacuum created by pumping the air out, but moreover a feather in a vacuum falls just as fast because it is no longer slowed by air resistance?

Also, fleep.
You've clearly given a lot of thought to this, have you reached a point at which you can lay out your theory quantitatively (in the form of equations?) I find that text is a very unsatisfactory medium for discussing the finer details of this sort of theory and this thread is getting very long winded and seems to the outside observer to be going in circles... If you expressed it (semi-)quantitatively it would be much easier to figure out where it does and doesn't match up with observed data.
 

fleep

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Atmospheric pressure and its effect
« Reply #105 on: 09/06/2007 15:07:54 »
Hi Batroost, BC and Rosy:

In messg 95887, Batroost said: This is a self-consistent model of events.  A different model is not excluded but neither does it appear to be necessary?

In 95997, Batroost said: Every example that you, I and BC have quoted fit the same model.

I suddenly realized this morning, that what is complicating this entire long debate, is my own continual insistence that my interpretations effectively challenge or try to disprove conventional theory. Batroost has smartened me up again, (above), as he did when he steered me towards constructing the “falling in atmosphere model” that I posted in my messg 86419. He accepted that and even complimented it. So, I had one model in place, which is effectively, a stand-alone way to observe an atmosphere-based event.

Now. Batroost says above that “A different model is not excluded, etc.” If I restart, I would present each model to consider on its own merits, keeping them each separate for discussion until I bring them all together for relative considerations. They will be logical constructions, and some may help me to refine them as they appear each in turn. When they seem to be "accepted (as models)", I will go on to each next model.

Whether actually necessary or not, the most recent is (I believe) my logical expression of how a functionally different display of pressure in a closed vessel in the vacuum of space still fits and confirms the tenets of (only) Pascal’s Law. That’s all it really does, and I mistakenly tackled the big guns, trying to say that it proved anything else wrong, when maybe all it really explains is an opinion of why things (gulp) “appear” to float in the air when inside a sealed ship in space.
 
I should be trying to identify only the fact that this pressure difference exists within Pascal, and that is, the “blind pressure” factor. It would then be presented as simply another model, which is open to interpretation, and makes no demands.

I have been overly ambitious, I suspect, in calling all of this exercise a “theory”. A theory demands mathematical evidence in most cases, and at my age, I am unequipped to learn the many things I must come to know. My life expertise is in other fields, and I'm retired. My models must stand alone as “Unique Observations” that fall outside the demanding parameters of theory. They are there, in that new circumstance, only for thought stimulation. I feel better already.

Perhaps, (and only perhaps), when my models are all completed and submitted together for their relational considerations, someone else can take them to a place I have always suspected that they will collectively lead, but it won’t be me that does it. Perhaps that will never even happen, but that’s my new mission anyway.

I am hereby asking the moderators for their opinion(s).

Do you wish me to cease and desist and go elsewhere, or should I restart in “Non-Life Sciences”? My new title might be something like “New Atmosphere and Vacuum Models.

Thank you to all who have participated and followed this long string.

fleep
 

Offline fleep

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Atmospheric pressure and its effect
« Reply #106 on: 31/07/2007 17:58:18 »
Hi; Fleep here. I'm back.

In the absence of any replies, I've decided to resume right here, where I left off.

Comparison – Earth Atmosphere Versus Shuttle Atmosphere
Purpose:
This thesis has been rewritten to redefine apparent reasons for the behaviour and its cause and effect on an object that is falling through space while “floating” in the captive atmosphere of the shuttle. The engines fire and the object “seems” to begin to “move” in relationship to its “floating position” in the ship, before engines were engaged.
First, we must restate Model 1, which explains what is happening when an object is dropped from rest speed at the Karman Line.  (Model 1 has been previously well received).

Purpose of Model 1 – Defining objects’ fall behaviour through Earth’s atmosphere.

It was Science that created a Datum area and weight (14.7 Lbs. per square inch), to satisfy a globally comparative need for a baseline. I am simply rising up from that "any one square inch" in a vertical column of the appropriate size, with an entire "Datum column" that extends up to the Karman Line, to be used for comparison(s).
Atmosphere of the Earth – Falling from 62 mi. – (A.k.a. – (Karman Line).

Model 1 - to track and explain the falling of a mass through Earth’s atmosphere.
===================================================

The jet stream is far away on this day, (North or South of our sample study.)
The day is still. The air all the way up to the Karman Line (62 miles) is not moving.
The area of each face of the 1 cubic inch block to be dropped is 1 square inch.
The object weighs 1 Lb., and is one cubic inch in volume.
Look at the column in which it is falling as a "soft closed vessel" of one sq. in. I.D.
It is a "(soft) closed vessel" because every other sq. in. I.D. column surrounding our example column is also one sq. inch I.D., and all contain the same gas "mix' for their strata level.
There is nothing special or distinct about the "column” in which our sample drops.
They are all close enough together that on a still day, all sq. in. I.D. columns are "soft closed vessels". (They are not actually “closed” to anything. This is for envisioning the model’s concept.)

Our 1 Lb. object will drop from the "Karman Line"/edge of space. (See Wikipedia)
All strata (gas) layers extend "flatly" identically at all altitudes in all directions.
Our sample object starts from the Karman Line & falls at 32 fps, then 32fps/sec. etc.
Its 1 Lb. weight falls and displaces one cubic inch of air at a time.
The cube’s passing "bends" the soft adjacent cubic inch "walls", displacing air.
Each succeeding cubic inch of fall recalls its air volume to re-fill the void above it.
The cube passes, so the original atmospheric weight above it is restored.
All bypassed cubic inches/columns return to normal as the cube drops.
The "ripple action" continues all the way (of the drop) down to sea level.
The 1 Lb. cube is leaving an increasing atmospheric burden behind as it falls.
At sea level, the object hits and sinks into the water.
The atmosphere above it, in the column, is 14.7 PSI at the surface once again.
Up until the splash, the total weight in that column was 15.7 Lbs. (with the cube.)
After the splash, it went back to 14.7 PSI, without the cube's 1 Lb. weight.

The overhead air did not "cause" the cube to accelerate. The air moved aside to let the solid mass have its way, and then the air continuously returned to its temporarily "borrowed" space. The atmosphere itself is, of course, an independent “facility”, where bugs, and birds, and planes, and even pollution, are “visitors”, and their combined weights are simply being “accommodated”.

This is all to say, that a mass falls naturally through an atmosphere, without “need” (or presence) of any downward “attraction”, until it reaches/strikes its “floor”.
(End of Model 1 explanation).

Now, we return to the “Purpose” mentioned at the opening of this thesis:
-   to restate what I believe to be the cause and effect of an object that is falling through space while appearing to be “floating” in the captive atmosphere of the shuttle. The engines are fired, and the object “seems” to begin to “move” in relationship to its “floating position” in the ship, before the engines were fired.

The situation is this:
Our 1 cubic inch, 1 pound weight is “at rest” appearing to be in a “hovering position” in the globally equalized pressure (under Pascal’ Law) atmosphere of the shuttle, which, for simplicity sake, we will say is 14.7 PSI, as is our own atmosphere on Earth. Comparatively speaking, we could call its "hovering" position, “the Karman rest-point”, simply in order to keep the analogy in line with the performance of the Model 1 explanation above. The ship in this model is travelling in an orbit that is “horizontal” to Earth’s atmosphere below it.
When the shuttle’s rear rocket fires, the “hovering” block’s inertial state “appears” to be “broken”. (Newton’s 1st Law.) An “action” appears to commence.
Our block will appear to begin to move from the "Karman rest-point", toward and in the same direction as the engine’s thrust. (i.e.- the trailing end of thrust direction.)
Its’ seemingly apparent “fall” speed and direction will be relational to that of the ship’s line of travel.(Because of the globally equalized pressure in the ship, the “columns” referred to in Model 1 do not exist in the ship.)
The cube appears to fall in a straight line towards the thrust engine, passing and displacing one cubic inch of air at a time. (In reality, the entire volume of contained air is bypassing the cube that remains in position, at rest in the air.)
Each succeeding cubic inch of “apparent fall” recalls its air volume to re-fill the void behind it.
As the whole air volume passes the cube, the original atmospheric weight/pressure behind the cube is restored.
All bypassed cubic inches return to normal pressure as the cube appears to “drop”.
The "ripple action" continues all the way (of the apparent “drop”) to the trailing inner surface of the ship.
The 1 Lb. cube is leaving no increasing atmospheric burden behind as it appears to “fall”, because all the ship’s internal atmospheric pressure is globally equal.
At the completion of the air volume’s passing, the cube hits the rear surface.
The atmospheric pressure in the ship is unchanged anywhere. It is still globally equal.
===================================================
What appears to be missing in this example? The ship has certainly begun to move forward by the force exerted by the rocket’s engine, but inside the shuttle, without the actual expenditure of any “force” directly against it, the object has suddenly appeared to have begun to “move” towards the rear of the ship. There is no doubt that it is now located in a different place inside the ship, but if no force has been expended to foment a change of inertia, then nothing has “happened” to the block. No “action” has occurred, and no “equal and opposite reaction” has been made compulsory until the moving ship itself strikes the cube.
Is it logical to say that the imposition of a globally equal interior pressure (under Pascal’s Law), has placed this scenario in a “theatre” in which Newton’s Laws of Motion have been “altered”, or even been nullified?
Does it perhaps now seem logical, that objects which appear to be floating in the air in a rocket ship are actually “suspended”, because the global equality of pressure provides no directionally explicit “orders” for objects to be “assigned” a place to rest? Unlike a hydraulic system, the “blind” atmospheric pressure, simply “cannot know” that loose things normally reside on a surface. This seems quite possible and even likely, in the absence or alteration of the Laws of Motion.
Why is this even of any importance? Who might care that the former explanation that “objects only appear to float because they are falling at the same rate as the ship”, is not a genuine reason for this unique anomaly?
Is it not enough to realize that possibly a single new truth can be added to human knowledge? If something occurs in only one specific circumstance, science deserves something better than mediocrity, and this is nothing but my tiny effort to bring a new possibility into the light.

Thanks for your patience.

Fleep
 

Offline fleep

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Atmospheric pressure and its effect
« Reply #107 on: 15/08/2007 18:05:16 »
Hey! Batroost and B.C. What's the matter with you two? Don't you want to debate anymore?

What if I elaborate a bit....
Here's another short explanation of what the long foregoing message means:

Inside the closed cabin of the shuttle, the atmosphere is equalized in a global way at something slightly less than 14.7 PSI. Pascal says that pressure is equal on all surfaces here, including on the objects that are “floating”. If the ship was equalized at precisely 14.7 PSI, it would be exactly the same pressure as at our sea level, so “floating” objects moving through a shuttle’s atmosphere are already effectively at, (or close to),  “sea level pressure” when they begin to (appear to) “move” as the engine is fired. That specific pressure of 14.7 PSI (on the Earth), is exactly adjacent to either the surface of water, or of solid matter. In the shuttle, there is no opportunity or demand for floating things to “fall” in any direction, because the surrounding pressure of those objects has already been “satisfied” by global pressure equalization. Objects “floating” in the shuttle’s atmosphere, are already (effectively), sitting on a “surrounding surface” (of air pressure). The only thing that moves is the ship, and the floating object just stays there in a fall rate that is exactly the same as the rate of the falling ship.
Because of the exterior acceleration of the ship, the object is simply bypassed by the ship’s atmosphere as the ship’s length goes by it. The object does not move.
I just would like anybody to tell me what’s not logical about this interpretation of what’s happening.

Any takers?

Thanks

fleep


 

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Atmospheric pressure and its effect
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