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Author Topic: thrust does not work in space  (Read 58407 times)

truthseeker67

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Re: thrust does not work in space
« Reply #25 on: 08/09/2013 00:01:14 »
of course the satellites are up there if you fired a canon ball from a massive gun that be up there too heheh only joking .

 Tom Wolfe's book "The Right Stuff" documents high altitude flight tests with rocket powered aircraft that would invariably fail in the thin air and plummet back to earth. Chuck Yeager almost died in a NF-104A rocket plane failure while attempting to set a height record. These planes were liquid fuel rockets and not air-fed jets.

Why would NASA claim to be able to send rockets into space when the USAF couldn't get the same technology into even the upper atmosphere?

Why did Chuck Yeager not join the space program? Did he know it was a hoax?
And like I said the x15 rocket plane was more than worthy with its own contained
Oxidizer but couldn’t make the trip.
I think its time to wake up folks and smell the coffee. I know it’s a very elegant fantasy to think of space travel but it only happens in the movies so enjoy them.
 

Offline dlorde

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Re: thrust does not work in space
« Reply #26 on: 08/09/2013 14:55:29 »
of course the satellites are up there if you fired a canon ball from a massive gun that be up there too heheh only joking .
Of course you're joking; because, apart from the satellites, you also have to account for these missions.
 

lean bean

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Re: thrust does not work in space
« Reply #27 on: 08/09/2013 17:08:38 »
Truthy #4
Quote
the thrust of a rocket engine has to have something to push against it cant push against its self.
The problem with applying Newton’s 3rd is that the rocket’s propellant does not generate force in a vacuum according to the laws of physics and chemistry.
Free Expansion states that when a pressurized gas is exposed to a vacuum the gas expanding into the vacuum without any work being done. The gas is not “pulled” or “sucked” into the vacuum nor is it “pushed” out of the high-pressure container. In other words no work is done,

truthseeker67
Imagine a hollow cube in interstellar space, at the centre of this cube there is an explosion. Each inner wall of the cube will receive an equal pressure (push) from the expanding gasses of that explosion, and so the cube does not move in any direction.

Take away one wall of that cube, and repeat the central explosion.
Again, the gaseous particles hit all walls with equal pressure except the missing wall. The pressure on the wall opposite that missing wall is not countered, and so the cube moves in the direction opposite to the missing wall.
Thrust in interstellar space.

« Last Edit: 08/09/2013 17:10:58 by lean bean »
 

truthseeker67

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Re: thrust does not work in space
« Reply #28 on: 08/09/2013 20:38:41 »
hi leanbean i can see what you mean with the cube it just when i look at photos of satellites in space the backgrounds are always completely black no stars are ever present in the pics look at this one of the  Hubble telescope taken from the shuttle heres the link look at the pic and enlarge it see what you think  http://en.wikipedia.org/wiki/Hubble_Space_Telescope
 

Offline dlorde

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Re: thrust does not work in space
« Reply #29 on: 08/09/2013 20:59:15 »
... when i look at photos of satellites in space the backgrounds are always completely black no stars are ever present in the pics look at this one of the  Hubble telescope taken from the shuttle heres the link look at the pic and enlarge it see what you think  http://en.wikipedia.org/wiki/Hubble_Space_Telescope
The brightness of the light reflected from the satellite that means the exposure is necessarily too short to register the starfield.

Check out this site, it will explain a lot of stuff you don't seem to understand, such as the absence of stars in many photos.
« Last Edit: 08/09/2013 21:01:29 by dlorde »
 

Offline alancalverd

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Re: thrust does not work in space
« Reply #30 on: 08/09/2013 22:01:29 »
Blimey! So my transatlantic phone link, GPS navigation systems, and even television, are all the products of a massive conspiracy!

Fair enough, but why do the fakers and conspirators take so much trouble to help me run my business, fly and drive from point to point, and watch The Simpsons? And how do they find the time to do it for everyone else as well?  And why do they bother to introduce such long transmission time delays, when I would have been perfectly happy thinking it was done with a direct cable?  It's a great service, and ridiculously cheap. I'm amazed.
 

Offline CliffordK

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Re: thrust does not work in space
« Reply #31 on: 09/09/2013 08:42:18 »
I watched the lunar conspiracy theory video.  They did make some interesting points.  However, one might be tempted to ask where all the moon rocks came from??? 

Here are some "new" photos of the landing sites on the moon.

http://www.nasa.gov/mission_pages/apollo/revisited/
http://www.nasa.gov/mission_pages/LRO/news/apollo-sites.html
 

truthseeker67

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Re: thrust does not work in space
« Reply #32 on: 09/09/2013 09:32:26 »
when i started this post i never doubted that satellites were not up there. Of course i know they orbit the earth. The topic is thrust doesn't work in space true space and all the satellites are in lower orbit where i do believe thrust works. I think people either haven't read my post from the beginning or have read it and forgot what i said only a page ago.

Oh yes Cliff was looking at what you posted me and was also checking out the camera thing i can see that the correct shutter speed and exposure time must be right for a given situation in order for small illuminated objects to show in background.
 

Offline alancalverd

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Re: thrust does not work in space
« Reply #33 on: 09/09/2013 10:31:15 »
So, uniquely among mankind, you do not understand the principle of conservation of momentum, but you simultaneously believe that satellites are in orbit.

You should ask yourself, therefore, what is keeping them up there? Everything I have ever flown has either been lighter than air or fitted with wings. Do satellites, which are heavier than air and have no wings, have some kind of magic power that we ordinary aviators and engineers don't know about? Why don't we use it for everyday travel? 
 

Offline dlorde

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Re: thrust does not work in space
« Reply #34 on: 09/09/2013 11:17:19 »
when i started this post i never doubted that satellites were not up there. Of course i know they orbit the earth. The topic is thrust doesn't work in space true space and all the satellites are in lower orbit where i do believe thrust works.
If thrust only works with air to push against, it would become less efficient with altitude, so that at low Earth orbit, there wouldn't be enough atmosphere for thrust to be effective. That would mean a rocket would need so much propellant to reach orbital velocity or escape velocity, it would never get off the ground.

Returning to reality - what about the geostationary communications & weather satellites at 35,786km out? they need an orbit change to achieve circular geostationary orbit (see Geostationary Transfer Orbit). This requires a thruster (rocket engine) burn - in space.

What about the Solar and Heliospheric Observatory (SOHO),the  Global Geospace Science (GGS) WIND, and the Advanced Composition Explorer (ACE) in unstable halo orbits at the L1 Lagrangian point?

Both geostationary and L1 satellites require orbital station-keeping, due to orbital instabilities (other satellites also need occasional orbital or attitudinal adjustments), and this also requires the use of thrusters - which are rocket engines.

Assuming you are serious and not trolling, your persistence in the face of overwhelming contrary evidence has the hallmarks of delusion - a delusion is a belief held with strong conviction despite superior evidence to the contrary.
 

Offline Pmb

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Re: thrust does not work in space
« Reply #35 on: 09/09/2013 14:30:26 »
Quote from: truthseeker67
Why did Chuck Yeager not join the space program? Did he know it was a hoax?
Read a book and learn that he wanted to be an astronatu but wasn't qualified. I.e. NASA required astronauts to have a college education, not simply a highschool education, to be an astronaut. Simple, huh?

I've ignored the rest of your posts because it's crystal clear to me that you have absolutely no idea about what you're talling about. Every single thought that you've posted is wrong.

Let this one go, folks. It's ot worth your time arguing with him. He doesn't know enough basic physics to carry on a simple conversation.
« Last Edit: 09/09/2013 16:48:17 by Pmb »
 

lean bean

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Re: thrust does not work in space
« Reply #36 on: 09/09/2013 16:41:26 »
hi leanbean i can see what you mean with the cube it just when i look at photos of satellites in space the backgrounds are always completely black no stars are ever present in the pics look at this one of the  Hubble telescope taken from the shuttle heres the link look at the pic and enlarge it see what you think  http://en.wikipedia.org/wiki/Hubble_Space_Telescope
Why do you link to a photo of Hubble, which is in low earth orbit, and then make the point of saying there's 'no stars' in that photo. Have you changed your mind now and saying things can't even be in low earth orbit because the absence of  stars proves hubble is not in space at all??

Truthy
Quote
when i started this post i never doubted that satellites were not up there. Of course i know they orbit the earth. The topic is thrust doesn't work in space true space and all the satellites are in lower orbit where i do believe thrust works.
Ttruthy
Quote
hi leanbean i can see what you mean with the cube

So I didn't convince you about thrust in interstellar space? aho. What's do you think is wrong about the cube explanation of thrust?


 
« Last Edit: 09/09/2013 16:53:55 by lean bean »
 

Offline Pmb

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Re: thrust does not work in space
« Reply #37 on: 11/09/2013 10:47:22 »
Okay. It’s time, once and for all, to show in detail why is wrong. In the very first sentence in this thread he writes
Quote from: truthseeker67
the reason why thrust cant work is simple
thrust equals = weight in order to have weight we need gravity.
see its like this in space everything weighs nothing so i would say a rocket weighs 0
or put like this rocket =0
His error is the invalid assumption that “thrust equals weight.” I explained this all too simple fact to him and he didn’t understand it. Nobody can use an invalid assumption to prove anything. He tried to prove me wrong by arguing, wrongly, that
Quote from: truthseeker67
look when water comes out of a hosepipe with high pressure it is simply chucking out
weight, ..
truthseeker67 = A hosepipe does not “chuck out” weight since that’s a meaningless statement.

And your comment right here requires special attention. You admit that water coming out of a hose causes force to be exerted on the hose in the direction opposite to the direction the water is coming out of. The problem with your argument is that the force exerted by the water is independent of the direction the water is ejected. It therefore cannot depend on the force of gravity and therefore cannot depend on gravity

Quote from: truthseeker67
…and thrust is weight ..
This invalid belief you keep trying to pass on is the source of your misconceptions on this topic. I.e. you simply don’t understand the meaning of the term “thrus” or “gravity”

Quote from: truthseeker67
.. do you think rocket engines are said to create pounds of thrust,…
I know that they do. It’s you who don’t know why they do.

Quote from: truthseeker67
… so then what are pounds …
I’d say to look it up but you keep refusing to do so. You don’t seem to like using dictionaries. Probably because they prove you wrong.

The term pound is the British unit of force whereas the SI unit is the Newton. See? You don’t know what it mean!

Quote from: truthseeker67
.....see pounds are weight.;.
Why don’t you do so yourself?
And your example contradicts your assumption since the water in a hosepipe will work even in the absence of gravity. Had you taken my advice and actually looked up the term in a dictionary or a physics text then you’d have learned that. But you didn’t, did you? You didn’t want to look it up because you’d see that I was right and you were wrong!
If you knew how a hose spitting out water caused there to be a force exerted back on it then you’d understand the error of your ways. Since you don’t know why then that’s proof enough for everyone to understand why you’re so wrong.

There are two definitions of the term weight. One is defined at http://en.wikipedia.org/wiki/Weight
Quote
weight - the weight of an object is usually taken to be the force on the object due to gravity.
The other is defined in The equivalence principle and the question of weight by Kenneth Nordtvedt Jr., Am. J. Phys., 43(3), Mar. (1975) [http://link.aip.org/link/ajpias/v43/i3/p256/s1] which reads
Quote
The weight of a body is meant to be the forces (e.g. the compression of a spring scale) required to either support the body in a gravitational field (gravitational weight) or to accelerate a body relative to an inertial system.
Quote from: truthseeker67
..because without gravity there is no weight behind the thrust.
Oy vey! You keep saying this and it’s not true.
The rest of what you say is nonsense.
 

Offline Pmb

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Re: thrust does not work in space
« Reply #38 on: 11/09/2013 11:17:18 »
Quote from: truthseeker67
could you imagine all the heat the vessels would absorb in space even with the protection they claim they have, keeping them cool just on batteries or whatever i know they use materials to reflect heat but even a mirror in the sun can get very hot. The outer shell of a spacecraft is acting a bit like a flask but sooner or later that heat is coming through. Read about the damage and problems the sun and radiation causes the satellites in orbit.
All of this is extremely wrong. Scientists knew how wrong this was long before they put satellites into orbit. And you admit that scientists put satellites into orbit so you must know how wrong it is.

The complete explanation regarding cosmic rays is given here
http://en.wikipedia.org/wiki/Health_threat_from_cosmic_rays

The other forms of radiation spoken about in this context comes from forms. They are;

Electromagnetic radiation (gamma rays, x-rays, ultraviolet rays, light waves, infrared rays, radio waves)

Beta radiation - electrons

Alpha radiation – nuclei of He atoms
 

Offline Pmb

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Re: thrust does not work in space
« Reply #39 on: 11/09/2013 11:21:16 »
The most obvious reason why truthseeker67 is wrong comes from his own example; the water hose. Let the water coming out of a firehose be pointed onto and at a person. The force on that person, i.e. the force exerted on the person by the water, would cause the person to topple over due to the force the water exerts on the person. This is due to the time rate of change on momentu that the person exerts on the water.
 

Offline alancalverd

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Re: thrust does not work in space
« Reply #40 on: 11/09/2013 11:24:02 »
The fundamental problem seems to be that our correspondent does not understand the difference between mass and weight. Therefore any talk of force and momentum is wasted on him.

Clearly the last 2000 years of scientific discovery and education have not penetrated the fog of misunderstanding perpetrated by Aristotle, Galileo died in vain, and Newton was just another farmer with an orchard.

Fortunately for the rest of us, Newtonian physics seems to work pretty well everywhere. But there's no point in arguing against a conviction. Just beware of anyone calling himself Truthseeker who offers to fly, drive or shoot anything for you. 
 

Offline Pmb

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Re: thrust does not work in space
« Reply #41 on: 11/09/2013 12:03:06 »
The fundamental problem seems to be that our correspondent does not understand the difference between mass and weight. Therefore any talk of force and momentum is wasted on him.

Clearly the last 2000 years of scientific discovery and education have not penetrated the fog of misunderstanding perpetrated by Aristotle, Galileo died in vain, and Newton was just another farmer with an orchard.

Fortunately for the rest of us, Newtonian physics seems to work pretty well everywhere. But there's no point in arguing against a conviction. Just beware of anyone calling himself Truthseeker who offers to fly, drive or shoot anything for you. 
alancalverd, my good man! I couldn't have said it better myself, so from now on I won't. Thank you so much!
 

truthseeker67

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Re: thrust does not work in space
« Reply #42 on: 11/09/2013 16:21:17 »
Let's try to boil down just why a properly executed fuel explosion within a craft would not be able to move the craft.

If there were a successful chemical explosion or comparable force outside the craft, and at its rear, it should propel the craft forward at least a small amount. However, if the explosion is internal — as we are led to believe — this would cause equal work in all directions and hence do nothing except stress the inside of the craft.

Only by somehow releasing a strategic percentage of the explosion to the infinitely permissive vacuum would the remainder do any work against the ship and cause it to move. But how could this be accomplished using the same rockets that are meant to propel the ship via thrust against air pressure?

Given that these "maneuvering in space" rockets are different rockets for a different purpose, safely nestled amongst the original Earth-based rockets, we are supposed to believe that the force of their internal explosions alone is moving and directing the craft in space, rather than thrust against anything as it works on Earth. So I guess we are meant to believe that NASA has found a way to transition their crafts' functions — as they ascend — from Earth physics to vacuum physics. I guess this would be a delicate process given that in the vacuum:

- conventional explosions would not be fed by adequate oxygen
- air pressure could no longer be used for lift
and
- lack of pressure outside the ship would cause extreme stress on the inside of all mechanisms with pressure

In other words, the amusing little jets of gas we see exiting the craft for 'course correction' cannot possibly be what they look like: just a gas being released into the vacuum. They must instead be representations of an internal, highly controlled and precise explosive force aimed at the inside of the craft itself, and the "jet" pictured is merely the residual energy that must escape to prevent the chamber from blasting open?

Do we have any schematics of how the.. "we are in the vacuum now" jets are supposed to work, and fit in/amongst the other functions of the craft?
 

Offline dlorde

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Re: thrust does not work in space
« Reply #43 on: 11/09/2013 17:37:24 »
... how could this be accomplished using the same rockets that are meant to propel the ship via thrust against air pressure?
There's your problem.

Rockets work the same way (action-reaction) in air or space. They don't work better by 'thrusting against air pressure'; if anything, air resistance against a rocket makes it less effective in air, requiring more fuel.

The fuels used in rockets don't need external oxygen (neither do most 'conventional' explosions); solid fuels have an oxidizer mixed in, liquid fuels are usually hypergolic, i.e. two liquids that combust when mixed. Some thrusters may use compressed gas or electromagnetically accelerated plasma (ion engines).

This is all basic school-level physics.
« Last Edit: 11/09/2013 18:55:02 by dlorde »
 

lean bean

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Re: thrust does not work in space
« Reply #44 on: 11/09/2013 19:31:01 »
If there were a successful chemical explosion or comparable force outside the craft, and at its rear, it should propel the craft forward at least a small amount.
The explosion chamber of a rocket engine is open to space on one side via the nozzle.
Truthy
Quote
However, if the explosion is internal — as we are led to believe — this would cause equal work in all directions and hence do nothing except stress the inside of the craft.
You forgot to mention the missing wall, so it is open to space. On a rocket that opening would be a nozzle or something bigger.

Thruthy
Quote
In other words, the amusing little jets of gas we see exiting the craft for 'course correction' cannot possibly be what they look like: just a gas being released into the vacuum. They must instead be representations of an internal, highly controlled and precise explosive force aimed at the inside of the craft itself,
Do you mean the explosive pressure on the front of the chamber is pushing the rocket forward because that forward thrust is not countered because of the rear opening in the chamber wall called a nozzle?

What was your point about the 'no stars' in the Hubble photo?
« Last Edit: 11/09/2013 19:33:23 by lean bean »
 

Offline Pmb

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Re: thrust does not work in space
« Reply #45 on: 12/09/2013 03:13:36 »
Quote from: dlorde
This is all basic school-level physics.
And that's the problem. His lack of understanding of what thrust is has led him to believe all sorts of things. I've made many attempts to get him to look up the meaning of the term but those requests were ignored. I have no idea why but I imagine that if I had to learn what they were then he'd have to admit he made an error. In this case it appears that he thought he could prove something known to be quite true as wrong merely by changing the definition. That's a mark of pseudoscience if I ever heard one!
« Last Edit: 14/09/2013 12:15:58 by Pmb »
 

truthseeker67

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Re: thrust does not work in space
« Reply #46 on: 14/09/2013 19:27:36 »
someone just show me an experiment of a rocket working in a vacuum never mind the theory lets just see the reality .
 

Offline Pmb

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Re: thrust does not work in space
« Reply #47 on: 14/09/2013 19:55:20 »
Quote from: truthseeker67
someone just show me an experiment of a rocket working in a vacuum never mind the theory lets just see the reality .
Do you actually believe that every scientist here has a list of every experiment ever done in his mind readily recallable? Sorry but it doesn't work that way. Especially with something so simple that nobody needs an experiment to be done in order to know what will happen in a vacuum. I'm actually unable to understand how people think a rocket works in the atmosphere (but not in a vacuum).

To actually do such an experiment is very trivial. College class rooms have a glass bell from which the atmosphere can re readibly vacuumed out. A rubber hose can be left in. When air is let back in there will be a force on the hose from the air being let back in.
 Analysis of the hoses motion will tell you if truthseeker67 is right or every single physicist alive today (including me) and their teachers are correct. I'm betting on every physicicist alive today. Especially since they understand nature and truthseeker67 is not even willing to look up the term "thrust" in a dictionary or provide a realistic argument for his guesses. I know that I'm right because I know elementary physics. This is simply the principle conservation of momentum at work. It's what makes a person recoild back when he's hit with a sack of potatoes when one is lobbed at him.

So, still not willing to learn physics yet, huh?
« Last Edit: 14/09/2013 19:59:46 by Pmb »
 

Offline dlorde

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Re: thrust does not work in space
« Reply #48 on: 14/09/2013 21:13:21 »
someone just show me an experiment of a rocket working in a vacuum never mind the theory lets just see the reality .
The experiment is demonstrated every time a rocket fires in space - which happens often. Satellites, probes, space labs - they all do it.




 

Offline Pmb

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Re: thrust does not work in space
« Reply #49 on: 15/09/2013 02:28:25 »
Quote from: dlorde
]
The experiment is demonstrated every time a rocket fires in space - which happens often. Satellites, probes, space labs - they all do it.
His problem is (1) he doesn't want to pick up a dictionary and look up the term "thrust" to see how it's really defined as opposed to how he wants it to be defined and (2) he thinks there is a worldwide conspiracy to fool him, especially when it comes to communications satilites and the GPS system. All he has to do is contact NASA and they'd tell him where those experiments were done for which satelites/rocket engines but that'd prove him wrong too. That's not his way it seems.
 

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Re: thrust does not work in space
« Reply #49 on: 15/09/2013 02:28:25 »

 

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