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-   -   Merged: Rockets cannot propel in the vacuum of space. (https://www.internationalskeptics.com/forums/showthread.php?t=335934)

bruto 18th April 2019 03:45 PM

Quote:

Originally Posted by Gingervytes (Post 12668808)
In the direction of low pressure lol. Campfire smoke pressure moves up because there is low pressure at higher altitude

But it doesn't. Even if you can't believe anyone has been to space, some of us have been smoked out of our tents!

Gingervytes 18th April 2019 04:36 PM

Quote:

Originally Posted by JayUtah (Post 12669048)
He has conceded he doesn't have answers for any of these, but speculates that there may exist "technology" he doesn't know about and can't describe which accounts for these apparent products of space travel. In other words, after chiding everyone for their "religious" faith in NASA and space, he has simply invoked ineffable miracles to account for his beliefs.

It's pretty clear at this point which of us is exhibiting the religious-style belief.

Underground cables, google earth airplanes

Gingervytes 18th April 2019 04:37 PM

Quote:

Originally Posted by bruto (Post 12669281)
But it doesn't. Even if you can't believe anyone has been to space, some of us have been smoked out of our tents!

What do you mean it doesn’t? Do you see smoke expands towards the ground?

JayUtah 18th April 2019 04:44 PM

Quote:

Originally Posted by Gingervytes (Post 12669340)
What do you mean it doesn’t? Do you see smoke expands towards the ground?

Smoke is a solid aerosol. It doesn't expand or contract. It can, however, be entrained in relatively quiescent airflows. And yes, not all of those airflows move upwards.

Gingervytes 18th April 2019 04:44 PM

Quote:

Originally Posted by smartcooky (Post 12669245)
Utter poppycock.

Smoke expands up rather than down because the particles of which it is comprised are thrust upwards by thermal convection caused by the heat of the fire.

You can observe this when the smoke comes down again once it is clear of the updraft..

https://www.dropbox.com/s/xrzy3kdu4s...moke.jpg?raw=1
Try camping out more often. It will do you some good

Hot air rises because temperature makes the pressure go up and this creates a pressure gradient.

http://ww2010.atmos.uiuc.edu/(Gh)/gu.../prs/hght.rxml

JayUtah 18th April 2019 04:50 PM

Quote:

Originally Posted by Gingervytes (Post 12669339)
Underground cables...

How would that solve any of the problems mentioned?

Quote:

google earth airplanes
Explain how that works. I'm at my data center, some 35 km south of the city center. I have a satellite dish there that must be precisely aimed to within about 30 minutes of arc in order to contact the satellite in geostationary orbit. At my downtown office I have a similar dish aimed with similar precision. Then at one of my customer sites, 90 km north of the city center, there is a satellite dish aimed equally precisely at that very tiny spot in the sky. Communications ensue with few if any problems, and with various well known colloquial idiosyncrasies associated with such a network that would make spoofing difficult for anyone except insiders.

Explain how three antennas spanning nearly 100 kilometers can aim a sub-degree radio beam at the same spot in the sky and communicate freely at any arbitrary time of the day or night using "google earth airplanes." Keep in mind I will be asking you to do the actual parallax calculations.

JayUtah 18th April 2019 04:52 PM

Quote:

Originally Posted by Gingervytes (Post 12669348)
Hot air rises because temperature makes the pressure go up...

No, that's not how gas behaves. The pressure goes up with a rise in temperature only if the volume is constrained. There is no such constraint for air that's heated above a campfire. That's the basic gas law. Buoyancy requires a difference in density, not pressure. Hot air is less dense than cold air.

Meadmaker 18th April 2019 04:58 PM

Quote:

Originally Posted by Gingervytes (Post 12669348)
Hot air rises because temperature makes the pressure go up and this creates a pressure gradient.

http://ww2010.atmos.uiuc.edu/(Gh)/gu.../prs/hght.rxml

Ah, my Alma mater. I think they would be surprised at your interpretation of their information.

Any thoughts on balloons in space?

curious cat 18th April 2019 05:09 PM

Quote:

Originally Posted by sackett (Post 12668626)
You tell 'em, Gingervytes!

No, b'god, I'll tell 'em!

I'm a handloader. If I load a rifle cartidge with a light bullet and fire it off, it kicks. And if I load a cartridge with a heavier bullet & the same amount of powder & then shoot, IT KICKS HARDER!

Let's see how you answer that, skeptics.

.......................

Another person who shouldn't play with guns :-). The explanation goes back to F=m*a. As you are accelerating bigger mass, you get a bigger force. That simple. You may try argue the amount of energy is the same, limited by the size of the charge. Almost right, except in the case of the smaller bullet it gets out of the barrel before all the gunpowder burns. The heavier one gives it more time and the combustion is more complete - meaning more energy to do the job.
In the case of "no bullet at all" a lot (if not most) of the propellant will get out before it burns and the efficiency will be very small. Automatic weapons may not function for that reason - a "blanks attachment" may be needed to solve the problem. Note; in that case all the forces are confined inside the barrel and no outside "support" of some kind is involved.

Hellbound 18th April 2019 05:11 PM

Quote:

Originally Posted by Meadmaker (Post 12669365)
Any thoughts on balloons in space?

They liven up the place? Add a festive air?

curious cat 18th April 2019 05:15 PM

Quote:

Originally Posted by Gingervytes (Post 12668808)
In the direction of low pressure lol. Campfire smoke pressure moves up because there is low pressure at higher altitude

Slightly misguided here. The smoke doesn't go up because of lower pressure being there. It goes up because being warm it expanded and has lower specific weight than the surrounding air. Ask Archimedes for details.

curious cat 18th April 2019 05:17 PM

Quote:

Originally Posted by Meadmaker (Post 12668851)
But what about the balloon? Would the toy balloon fly about if you opened the neck of the balloon in the vacuum of space?

Yes.

JayUtah 18th April 2019 05:23 PM

Quote:

Originally Posted by Meadmaker (Post 12669365)
Ah, my Alma mater. I think they would be surprised at your interpretation of their information.

The linked information is correct, of course. It's just not the reason smoke rises. But both the smoke-rising and rocket-moving scenarios happen to have a common (wrong) explanation that follows from his poor understanding of the behavior of compressible fluids.

Quote:

Any thoughts on balloons in space?
How else are the astronauts going to kiester their contraband?

Pooneil 18th April 2019 05:59 PM

Quote:

Originally Posted by smartcooky (Post 12669245)

You can observe this when the smoke comes down again once it is clear of the updraft..

I remember one particular interesting scout camporee. We all lit our fires in the morning and the slow rising smoke from the first burn when up 20 or so feet from the ground, then stopped rising and floated sideways. It actual floated down with the the slope of the land. The camp, which had been under a clear sky before the fires was finally covered under a really cool haze. As soon as the sun broke, the smoke cleared.

Presumably a temperature inversion with the cool air flowing downstream, under the warmer air above, toward the nearby river. It was a great example for a 13 YO.

The Common Potato 18th April 2019 06:42 PM

Quote:

Originally Posted by Belz... (Post 12667241)
Jay, let me be the first to say: please never, ever die. You are a fountain of knowledge.

It's just too bad that the OP will ignore you.

This is my first post on International Skeptics. Feel honoured, Belz. :) I'm a long-time lurker and do concur with your thoughts about JayUtah.

I hope I've been able to use the quote function correctly. Let's see.

The Common Potato 18th April 2019 08:38 PM

Quote:

Originally Posted by Mojo (Post 12669171)
Just North of Watford, I expect.

I live in Scunthorpe. Does that count for anything?

Steve 18th April 2019 08:59 PM

Quote:

Originally Posted by The Common Potato (Post 12669502)
I live in Scunthorpe. Does that count for anything?

No. Nothing.






:D

EHocking 18th April 2019 09:27 PM

Quote:

Originally Posted by Belz... (Post 12667174)
I really wanted to fully understand that, but some of it went right over my head....

Well of course it did.
This is rocket science after all.

EHocking 18th April 2019 09:52 PM

I was disappointed that JayUtah didn’t answer this, so here’s you answer.
Quote:

Originally Posted by JayUtah (Post 12667627)
We did an design exercise once to see whether you could pee with enough thrust to lift yourself off an asteroid.

Probably NSFW
YouTube Video This video is not hosted by the ISF. The ISF can not be held responsible for the suitability or legality of this material. By clicking the link below you agree to view content from an external website.
I AGREE

LongFuzzy 18th April 2019 10:18 PM

This you tube video proves Gingervytes wrong:

(Space X Heavy Launch)
https://www.youtube.com/watch?v=vF_2kYAwMGw

T+00:03:43 (20:40 into the video) Stage 2 Engine start up.
Look at the lower left corner, you see speed and altitude.

T+00:27:38 (44:38 into the video) Stage 2 restart, at 199Km (123Miles)
Notice the speed indicator rapidly increasing.

Absolute proof that rockets work in space.

Oh, BTW, I think I found a Jay Utah typo. In post #351 next to last sentence, I think he meant right end cap, not left. Do I get a T shirt?:D

RecoveringYuppy 18th April 2019 11:34 PM

Quote:

Originally Posted by sts60 (Post 12668840)
Nope. The pressure gradient is negligible at such a short distance.

The pressure gradient is also "up", on average, everywhere. Why doesn't the atmosphere leave the planet I wonder.

curious cat 19th April 2019 12:12 AM

Quote:

Originally Posted by sts60 (Post 12668840)
Nope. The pressure gradient is negligible at such a short distance.

While this statement is true, it is not a key for the failure of the OP's principle. The real reason is, the smoke displays similar gradient. just nitpicking ;-).
And more as a matter of interest: depends on what we call "negligible". A basic barometric altimeter (I have several) has resolution of 1m, something what may come as a surprise to some.

Dave Rogers 19th April 2019 12:25 AM

Quote:

Originally Posted by Gingervytes (Post 12669339)
Underground cables, google earth airplanes

Limburger?

Dave

MRC_Hans 19th April 2019 12:33 AM

Quote:

Originally Posted by Steve (Post 12669032)
Does this mean that we have to concede that rockets don't work?

Well seens this particular rocket is not gonna fly. Not due tu any vacuum on its OUTSIDE, however.

Hans

GlennB 19th April 2019 12:47 AM

Quote:

Originally Posted by Dave Rogers (Post 12669581)
Limburger?

Dave

It escaped last night. Tricky blighter, Limburger.

Andy_Ross 19th April 2019 01:51 AM

Quote:

Originally Posted by Gingervytes (Post 12669339)
Underground cables, google earth airplanes

OK, I am on a ship in the middle of the ocean. How do I use a cable?
Why are my communications and data routed through a satellite dish on top of the bridge?
What is the dish pointing at? the nearest aircraft is thousands of miles away.
My navigation relies on GPS which uses a sat dish on the roof of the bridge. where does it get a signal?
Why doesn't GPS work exactly as described?

Mojo 19th April 2019 02:16 AM

Quote:

Originally Posted by Gingervytes (Post 12669348)
Hot air rises because temperature makes the pressure go up and this creates a pressure gradient.


Your hypothesis predicts that hot air will move outwards in all directions, not just up.

Belz... 19th April 2019 02:37 AM

Quote:

Originally Posted by Gingervytes (Post 12668420)
Quote:

Originally Posted by JayUtah
Irrelevant. Do you agree that if it has mass then Newton's third law applies?

Lets say a 75kg person lifts a 100kg weight and he drops it from a height. Why doesn’t that person get lifted off the ground? Isn’t the weight mass?

That was a yes or no question.

Belz... 19th April 2019 02:39 AM

Quote:

Originally Posted by Gingervytes (Post 12668578)
Do they go into space. Every rocket launch it looks like it went into the ocean

I think it's been well-established so far that the way things "look like" to you bear little ressemblance to reality.

Belz... 19th April 2019 02:44 AM

Quote:

Originally Posted by Gingervytes (Post 12668599)
Ok then solid piece.

I'm sorry your english is so weak.

Quote:

Originally Posted by Gingervytes (Post 12668651)
Have you seen a rocket go into space?

Yes, we have. Not only on video and TV, but through non-visual means as well. You know that non-pixelated videos can be evidence too, right?

Quote:

Originally Posted by Gingervytes (Post 12668793)
I already did. Pressure expand to least resistance and low pressure. Space provides no resistance and is near zero pressure

So the exhaust would all go in the same direction, correct? And so with equal reaction, the rocket would ______________ (fill the blank).

curious cat 19th April 2019 02:54 AM

Gingervytes:
"Lets say a 75kg person lifts a 100kg weight and he drops it from a height. Why doesn’t that person get lifted off the ground? Isn’t the weight mass?"

The keyword is "drops". The person is not exerting any force on the weight. He is simply letting gravity to do its job. If he "pushed" the weight down while it was falling to accelerate its descent over 9.81m/s^2, he could achieve a point where he would lift himself from the ground. I don't think anybody is fit enough to achieve this though ;-).

dann 19th April 2019 02:56 AM

Quote:

Originally Posted by Gingervytes (Post 12669339)
Underground cables, google earth airplanes

Cream-colored ponies and crisp apple strudels
Doorbells and sleigh bells
And schnitzel with noodles
Wild geese that fly with the moon on their wings
These are a few of my favorite things
YouTube Video This video is not hosted by the ISF. The ISF can not be held responsible for the suitability or legality of this material. By clicking the link below you agree to view content from an external website.
I AGREE

Gingervytes 19th April 2019 03:19 AM

Quote:

Originally Posted by curious cat (Post 12669629)
Gingervytes:
"Lets say a 75kg person lifts a 100kg weight and he drops it from a height. Why doesn’t that person get lifted off the ground? Isn’t the weight mass?"

The keyword is "drops". The person is not exerting any force on the weight. He is simply letting gravity to do its job. If he "pushed" the weight down while it was falling to accelerate its descent over 9.81m/s^2, he could achieve a point where he would lift himself from the ground. I don't think anybody is fit enough to achieve this though ;-).

And in the case of a rocket. Pressure expands due to pressure gradient force and not because the rocket pushes it

SusanB-M1 19th April 2019 04:02 AM

Just posting to add my thanks to the scientists and rocket scientists who refute nonsense with sense and facts. It is so interesting to read even though I can't actually understand most of it.


ETA I did not notice before writing, but I think that's an appropriate, i.e. in science, post to reach 3,600!

GlennB 19th April 2019 04:43 AM

Quote:

Originally Posted by Gingervytes (Post 12669643)
And in the case of a rocket (1). Pressure expands (2) due to pressure gradient force and not because the rocket pushes it (3)

Could you rewrite that in comprehensible English please?

(1) And in the case of a rocket ... what?

(2) Pressure expands? Did you mean pressure increases? Or maybe gas expands?

(3) The rocket pushes it? What is it? Pressure? If so, it makes no sense.

phunk 19th April 2019 05:04 AM

Quote:

Originally Posted by Gingervytes (Post 12669643)
And in the case of a rocket. Pressure expands due to pressure gradient force and not because the rocket pushes it

Ok let's go with your theory for one sec. Imagine a lot of gas released into the vacuum of space. It is unconstrained and expanding in all directions. If there were an object next to that cloud, would it be pushed even the slightest bit by the wind then the expanding cloud contacted it?

Mojo 19th April 2019 05:18 AM

Quote:

Originally Posted by Gingervytes (Post 12669643)
And in the case of a rocket. Pressure expands due to pressure gradient force and not because the rocket pushes it


Does the exhaust from a rocket expand equally in all directions? Come on, it’s a simple enough question, requiring only a single word to answer it.

JayUtah 19th April 2019 05:36 AM

Quote:

Originally Posted by Gingervytes (Post 12669643)
And in the case of a rocket. Pressure expands...

"Expanding pressure" is not a thing in physics.

Quote:

...due to pressure gradient force and not because the rocket pushes it
I explained at some length yesterday exactly how the "pressure gradient force" results in motion. I notice you've been entirely silent about that. Now you're just mindlessly repeating the same garbled, incoherent mantra without being able to engage your critics at anything other than that superficial level.

Here's the link.
http://www.internationalskeptics.com...2#post12668972

Try again. Yes, it's lengthy. That's because it's thorough. It starts from basic principles and takes a methodical, step-by-step inductive approach to show how "pressure gradient force" actually works in a rocket.

Meadmaker 19th April 2019 06:46 AM

Quote:

Originally Posted by Gingervytes (Post 12669643)
And in the case of a rocket. Pressure expands due to pressure gradient force and not because the rocket pushes it

So...….the balloon? We know what happens in the atmosphere. What would happen in space?

Belz... 19th April 2019 07:02 AM

Quote:

Originally Posted by JayUtah (Post 12669692)
"Expanding pressure" is not a thing in physics.

One more indication that he doesn't know anything about the topic, and yet he thinks he's going to overturn the current theories.


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