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 International Skeptics Forum Merged: Rockets cannot propel in the vacuum of space.

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 13th June 2019, 07:11 AM #3361 jadebox Graduate Poster     Join Date: Sep 2004 Location: USA Posts: 1,682 Originally Posted by Ranb I'm assuming that the guy is pushing a bowling ball to generate the force to move himself backward? Gingervytes would say that the reaction is solely due to the ball pushing on the air. I would say to Gingervytes, if that is true then you should be able to replicate the results of the experiment without releasing the ball. Just push it against the air and you should move in the opposite direction the same distance as the guy in the video does. Wanna give it a try? For those of us living the real universe, we could move back and forth by extending the ball as if we were going to throw it. The center of mass shared by the ball and the person and the sled, however, would stay the same. Friction and air resistance mess that up a little. You would probably be able to make the center of mass move some. In a vacuum with a frictionless sled, however, you would not be able to move the center of mass EVEN IF YOU ACTUALLY THROW THE BALL. (That, BTW, is proof that a rocket motor will work in a vacuum. Sorry Gingervytes.) Last edited by jadebox; 13th June 2019 at 07:26 AM.
 13th June 2019, 07:46 AM #3362 pgwenthold Penultimate Amazing   Join Date: Sep 2001 Posts: 18,693 Originally Posted by jadebox Gingervytes would say that the reaction is solely due to the ball pushing on the air. But that doesn't make any sense. Once the kid let's go of the ball, whatever happens to the ball is irrelevant to him (this is a point I keep making about the gas exiting the rocket). As you say, if that has any bearing in reality, you would get the same effect by not releasing the ball. Let's see that demo? __________________ "As your friend, I have to be honest with you: I don't care about you or your problems" - Chloe, Secret Life of Pets
 13th June 2019, 08:01 AM #3363 Jack by the hedge Safely Ignored     Join Date: Oct 2009 Posts: 10,057 Originally Posted by jadebox Gingervytes would say that the reaction is solely due to the ball pushing on the air. I would say to Gingervytes, if that is true then you should be able to replicate the results of the experiment without releasing the ball. Just push it against the air and you should move in the opposite direction the same distance as the guy in the video does. Wanna give it a try? Perhaps more significantly, if the force pushing the guy on the trolley backwards came from pressurised air in front of the ball, it would work equally well if he threw a similarly sized balloon.
 13th June 2019, 08:01 AM #3364 pgwenthold Penultimate Amazing   Join Date: Sep 2001 Posts: 18,693 This whole "pressure gradient force" stuff is really dumb. Newton's 3rd law has nothing to do with "pressure gradients." It's about the conservation of momentum. When I think about gas-phase physical chemistry, in fact, I don't think about Newton's 3rd law. I think about the conservation of momentum. We see the consequences of that (and the manifestation of Newton's 3rd law) all the time in kinetic behavior of gaseous particles. For example, in Coulombic explosion or any type of scattering, you describe the behavior of the system by imposing a conservation of momentum. And when you do that, have an en equal and opposite force. Personally, I've never been all that enamored with Newton's 3rd law, which, to me, has always been a natural consequence of the conservation of momentum. As jadebox points out, the momentum of the center-of-mass is going to be constant (and zero if you work in the center-of-mass frame of reference). Therefore, if you blow mass out one direction (creating momentum in that direction), the only way to maintain the momentum in the center-of-mass frame is to push something in the other direction to compensate. It has to happen, or you violate the conservation of momentum. __________________ "As your friend, I have to be honest with you: I don't care about you or your problems" - Chloe, Secret Life of Pets
 13th June 2019, 09:49 AM #3365 Elagabalus Philosopher   Join Date: Dec 2013 Posts: 5,511 Originally Posted by Gingervytes And how does this information prove that there is an equal and opposite force from gas movement due to pressure gradient force? Why do we have time zones GV?
 13th June 2019, 10:38 AM #3366 fuelair Banned     Join Date: May 2006 Posts: 58,581 Amazingly, Gv is still posting and either incompetent, ignorant or untruthful (or all 3)as there are no other options that hold rationality/truth/accuracy as one of his/her skillsets. I know of no way he/she could be more wrong.
 13th June 2019, 12:09 PM #3367 Trebuchet Penultimate Amazing     Join Date: Nov 2003 Location: The Great Northwet Posts: 25,908 Originally Posted by fuelair Amazingly, Gv is still posting and either incompetent, ignorant or untruthful (or all 3)as there are no other options that hold rationality/truth/accuracy as one of his/her skillsets. I know of no way he/she could be more wrong. Just spamming videos. __________________ Cum catapultae proscribeantur tum soli proscripti catapultas habeant.
 13th June 2019, 05:36 PM #3368 Reality Check Penultimate Amazing   Join Date: Mar 2008 Location: New Zealand Posts: 26,516 __________________ NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist!
 13th June 2019, 05:45 PM #3369 Reality Check Penultimate Amazing   Join Date: Mar 2008 Location: New Zealand Posts: 26,516 Persists with a delusion of "alleged space missions and satellites" Originally Posted by Gingervytes Indirect evidence like alleged space missions and satellites is not acceptable 14 June 2019 Gingervytes: Persists with a delusion of "alleged space missions and satellites" Anyone with eyes can see satellites. Anyone with a telescope and a couple of brain cells can see the details of the ISS and know that it is not in the atmosphere - unless they are demented enough to believe in ISS shaped aircraft flying around! it is also aerodynamically impossible for other satellites to be flying around in the atmosphere because they have solar panels, antenna and are just the wrong shape . 14 June 2019 Gingervytes: An "Indirect evidence" lie when we have direct evidence of space missions and satellites. Eyes are direct evidence. Astronauts are direct evidence. Signals from satellites are direct evidence. Tracking of space missions and satellites are direct evidence. It may be frowned upon, but I suspect that anyone can bounce radar off satellites and measure that they are in space. Obviously no flat earth or "alleged space missions and satellites" crackpots have been brave enough to do that. 14 June 2019 Gingervytes: Lies about his delusion which is that rockets do not work in space which is not a problem with rockets reaching space. Rockets working in the atmosphere allow space missions and satellites to get to Earth orbit. __________________ NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! Last edited by Reality Check; 13th June 2019 at 05:54 PM.
 13th June 2019, 05:51 PM #3370 Craig4 Penultimate Amazing     Join Date: Aug 2010 Location: Alexandria, VA Home to the Deep State. Posts: 19,690 Originally Posted by Reality Check 14 June 2019 Gingervytes: Persists with a delusion of "alleged space missions and satellites" Anyone with eyes can see satellites. Anyone with a telescope and a couple of brain cells can see the details of the ISS and know that it is not in the atmosphere - unless they are demented enough to believe in ISS shaped aircraft flying around! it is also aerodynamically impossible for other satellites to be flying around in the atmosphere because they have solar panels, antenna and are just the wrong shape . 14 June 2019 Gingervytes: An "Indirect evidence" lie when we have direct evidence of space missions and satellites. Eyes are direct evidence. Astronauts are direct evidence. Signals from satellites are direct evidence. Tracking of space missions and satellites are direct evidence. Remember, GV doesn't actually believe rockets don't work in space. He thinks the only reason pay attention to him is that he tells people rockets don't work in space.
 13th June 2019, 06:05 PM #3371 Reality Check Penultimate Amazing   Join Date: Mar 2008 Location: New Zealand Posts: 26,516 Lies again about Newton's third law Originally Posted by Gingervytes And how does this information prove that there is an equal and opposite force from gas movement due to pressure gradient force? 14 June 2019 Gingervytes: Lies again about Newton's third law which is not that every force has an equal and opposite force. That is obviously a lie because unequal forces exist, e.g. we can walk! Newton's third law Quote: The third law states that all forces between two objects exist in equal magnitude and opposite direction Pressure-gradient force is a force inside 1 "body" - a volume of gas. If we look at the forces between each pair of particles in that gas then Newton's third law applies. __________________ NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist!
 13th June 2019, 07:22 PM #3372 JayUtah Penultimate Amazing     Join Date: Sep 2011 Posts: 18,378 Originally Posted by Gingervytes The evidence I will accept is proof of an equal and opposite force from gas movement due to pressure gradient force. No, you don't get to insist on proof of your ignorant notions. Your entire notion of gas physics is wrong, and that's been proven several times. You don't even know what pressure is. Seriously, you don't. Quote: Indirect evidence like alleged space missions and satellites is not acceptable Space missions are direct evidence that rockets work. It's evidence, no matter how inconvenient that is to your worldview. You keep running screaming from the evidence. Why is that?
 13th June 2019, 08:07 PM #3373 JayUtah Penultimate Amazing     Join Date: Sep 2011 Posts: 18,378 Originally Posted by Craig4 Remember, GV doesn't actually believe rockets don't work in space. He thinks the only reason pay attention to him is that he tells people rockets don't work in space. It seems all he can do anymore is babble the same catch-phrase over and over. How boring.
 13th June 2019, 08:11 PM #3374 Robin Penultimate Amazing   Join Date: Apr 2004 Posts: 11,649 Newton's Third law pretty much applies to one body inside another being moved by pressure gradient force. For example a helium balloon in the atmosphere will have a given force from the air around and will exert that same force back on the air. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th June 2019, 03:45 AM #3375 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 Originally Posted by Craig4 Remember, GV doesn't actually believe rockets don't work in space. He thinks the only reason pay attention to him is that he tells people rockets don't work in space. She / He may as well be screaming “Pay attention to MEEEEEEEEEEEEE!!!!!!!!” __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 03:53 AM #3376 Craig4 Penultimate Amazing     Join Date: Aug 2010 Location: Alexandria, VA Home to the Deep State. Posts: 19,690 Originally Posted by halleyscomet She / He may as well be screaming “Pay attention to MEEEEEEEEEEEEE!!!!!!!!” Actually, after what I just saw in Conspiracy Theories, he might be screaming, "Pay attention to me; I need the money". He posted YouTube videos for all three of his threads. This is likely just an exercise to drive clicks to his monetized YouTube videos. I can't imagine it's all that lucrative. You'd need a lot of eyeballs to make any real money and most people here don't open YouTube videos linked in threads.
 14th June 2019, 05:16 AM #3377 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 Originally Posted by Craig4 Actually, after what I just saw in Conspiracy Theories, he might be screaming, "Pay attention to me; I need the money". He posted YouTube videos for all three of his threads. This is likely just an exercise to drive clicks to his monetized YouTube videos. I can't imagine it's all that lucrative. You'd need a lot of eyeballs to make any real money and most people here don't open YouTube videos linked in threads. He should give up and start making videos supporting Q. That's easy money for the morally bankrupt. __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 05:27 AM #3378 Gingervytes Critical Thinker   Join Date: Mar 2019 Posts: 286 Originally Posted by Robin That is easy and has already been given. P1: If there was no equal and opposite force from gas movement due to pressure gradient force then some particle interactions would happen without momentum being conserved. P2: No particle interactions happen without momentum being conserved Conclusion: There is equal and opposite force from gas movement due to pressure gradient force. (By modus tollens P1,P2) The proof is formally valid and both premises are true and so the argument is sound. If you are saying there is something wrong with this, you will have to tell me which premise you disagree with P1 or P2. Incidentally, as I have shown, even if we granted the absurd claim that there is no equal and opposite force from gas movement due to pressure gradient force, rockets would still work in a vacuum. They would just have a slower exhaust. Momentum is provided by pressure gradient force. Just like force is provided by gravity when you drop something. So momentum is conserved and no push on rocket.
 14th June 2019, 05:30 AM #3379 Gingervytes Critical Thinker   Join Date: Mar 2019 Posts: 286 Originally Posted by Reality Check 14 June 2019 Gingervytes: Lies again about Newton's third law which is not that every force has an equal and opposite force. That is obviously a lie because unequal forces exist, e.g. we can walk! Newton's third law Pressure-gradient force is a force inside 1 "body" - a volume of gas. If we look at the forces between each pair of particles in that gas then Newton's third law applies. Where is your proof? A demonstration proving exactly what you are saying is required
 14th June 2019, 05:33 AM #3380 JayUtah Penultimate Amazing     Join Date: Sep 2011 Posts: 18,378 Originally Posted by Gingervytes Momentum is provided by pressure gradient force. No. That's not what momentum means and that's not what pressure means. You've utterly failed to grasp the simplest concepts. Quote: Just like force is provided by gravity when you drop something. No, the conservation of momentum is not like gravity. Quote: So momentum is conserved and no push on rocket. No, you don't get to redefine basic concepts in Newtonian dynamics to make your broken model seem like it works. You've been given countless examples of how your model would break down under other circumstances, and you choose not to address them. I interpret that silence to mean you know your claim is full of crap.
 14th June 2019, 05:34 AM #3381 JayUtah Penultimate Amazing     Join Date: Sep 2011 Posts: 18,378 Originally Posted by Gingervytes Where is your proof? A demonstration proving exactly what you are saying is required No. The claimant does not get to decide what rebuttals are required or acceptable. If you want to prove you know what pressure is, answer all the questions you've conspicuously ignored.
14th June 2019, 05:43 AM   #3382
Robin
Penultimate Amazing

Join Date: Apr 2004
Posts: 11,649
Originally Posted by Gingervytes
Momentum is provided by pressure gradient force. Just like force is provided by gravity when you drop something. So momentum is conserved and no push on rocket.
Which premise do you say is wrong, P1 or P2?

And, yet again, the illustration below is of an area of expanding gas and a steel plate to the left of it and in open space with no other objects nearby.

So:

1. Which point has the greater pressure, A or G?
2. Will particles between A and G move towards A or towards G?
3. Given that there is nothing but vacuum between the moving particles and the steel plate, what will stop the particles from coming into contact with the steel?
Attached Images
__________________
The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"

Last edited by Robin; 14th June 2019 at 05:49 AM.

 14th June 2019, 05:46 AM #3383 Crossbow Seeking Honesty and Sanity     Join Date: Oct 2001 Location: Charleston, WV Posts: 12,887 Originally Posted by Gingervytes Momentum is provided by pressure gradient force. Just like force is provided by gravity when you drop something. So momentum is conserved and no push on rocket. You are a liar. __________________ On 22 JUL 2016, Candidate Donald Trump in his acceptance speech: "There can be no prosperity without law and order." On 05 FEB 2019, President Donald Trump said in his Sate of the Union Address: "If there is going to be peace and legislation, there cannot be war and investigation." On 15 FEB 2019 'BobTheCoward' said: "I constantly assert I am a fool." A man's best friend is his dogma.
 14th June 2019, 05:47 AM #3384 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 Originally Posted by Gingervytes Momentum is provided by pressure gradient force. Gingervytes is in fact two dogs wearing a trench coat banging on the keyboard with the edge of a fedora. I can assert this with the exact same level of confidence and evidence that Gingervytes uses when babbling about "pressure gradient force." If Gingervytes wants to object to my brilliant and irrefutable deduction then I want to know, where is their proof? A demonstration proving they are NOT two dogs wearing a trench coat is required. __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 05:50 AM #3385 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 You've all ASSUMED incorrectly (on purpose), that Gingervytes is a human. Their keyboard needs a fedora to push off of Mathematical proof that Gingervytes is two dogs in a trench coat:Attachment 39978 __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 06:08 AM #3386 Robin Penultimate Amazing   Join Date: Apr 2004 Posts: 11,649 Originally Posted by Gingervytes Where is your proof? A demonstration proving exactly what you are saying is required He is only saying the same thing that is said in the link you provided. Have you changed your mind about what pressure gradient force is? __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th June 2019, 06:13 AM #3387 MRC_Hans Penultimate Amazing     Join Date: Aug 2002 Posts: 22,591 Originally Posted by Gingervytes Where is your proof? A demonstration proving exactly what you are saying is required No, it is not required. You have the burden of proof because you are the one challenging the paradigm. Sorry, but such are the rules. There is plenty of evidence that rockets work in space. Hans __________________ Experience is an excellent teacher, but she sends large bills.
14th June 2019, 06:21 AM   #3388
BStrong
Penultimate Amazing

Join Date: Jun 2011
Location: San Francisco
Posts: 12,799
Originally Posted by halleyscomet
She / He may as well be screaming “Pay attention to MEEEEEEEEEEEEE!!!!!!!!”
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Music is what feelings sound like

"Dulce bellum inexpertīs." - Erasmus

 14th June 2019, 06:34 AM #3389 Robin Penultimate Amazing   Join Date: Apr 2004 Posts: 11,649 Originally Posted by halleyscomet You've all ASSUMED incorrectly (on purpose), that Gingervytes is a human. Their keyboard needs a fedora to push off of Mathematical proof that Gingervytes is two dogs in a trench coat:Attachment 39978 I don't know, I won't be completely convinced until I see a video of a dyson being waved at a keyboard. Or a fedora. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
14th June 2019, 06:40 AM   #3390
halleyscomet
Penultimate Amazing

Join Date: Dec 2012
Posts: 10,244
Originally Posted by Robin
I don't know, I won't be completely convinced until I see a video of a dyson being waved at a keyboard. Or a fedora.
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via Imgflip GIF Maker
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Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!

Last edited by halleyscomet; 14th June 2019 at 06:43 AM.

14th June 2019, 06:55 AM   #3391
Robin
Penultimate Amazing

Join Date: Apr 2004
Posts: 11,649
Originally Posted by halleyscomet
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I am convinced. If only the mainstream media Ultra Mario Kart Konspiracy was not keeping this from the public.
__________________
The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"

 14th June 2019, 07:01 AM #3392 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 Originally Posted by Robin I am convinced. If only the mainstream media Ultra Mario Kart Konspiracy was not keeping this from the public. To be fair it's more apathy keeping this under wraps than anything else. The idea of dogs being online is cool, until you read the crap they post. Nobody wants to think about a dog posting the crap Gingervytes bangs out with their fedora. Note to Moderators: I believe my comments asserting Gingervytes is in fact two dogs in a trench coat typing with a fedora is on-topic, as it is a deliberate and targeted parody of the arguments Gingervytes uses regarding pressure gradient force. I am not attacking Gingervytes, but the dogged insistence upon repeating the same catch phrase in defiance of all evidence about rockets working in space. __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 07:07 AM #3393 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 07:08 AM #3394 MRC_Hans Penultimate Amazing     Join Date: Aug 2002 Posts: 22,591 Originally Posted by halleyscomet To be fair it's more apathy keeping this under wraps than anything else. The idea of dogs being online is cool, until you read the crap they post. Nobody wants to think about a dog posting the crap Gingervytes bangs out with their fedora. Note to Moderators: I believe my comments asserting Gingervytes is in fact two dogs in a trench coat typing with a fedora is on-topic, as it is a deliberate and targeted parody of the arguments Gingervytes uses regarding pressure gradient force. I am not attacking Gingervytes, but the dogged insistence upon repeating the same catch phrase in defiance of all evidence about rockets working in space. Double-dogged, as it were ... Hans __________________ Experience is an excellent teacher, but she sends large bills.
14th June 2019, 07:17 AM   #3395
halleyscomet
Penultimate Amazing

Join Date: Dec 2012
Posts: 10,244
Originally Posted by MRC_Hans
Double-dogged, as it were ...
It gets better. Finding video of dogs being vacuumed is just as easy as finding unedited video of rockets being launched into space!

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The body of evidence exposing the "two dogs in a trench coat" hypothesis is growing rapidly.
__________________
Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!

 14th June 2019, 08:22 AM #3396 Jack by the hedge Safely Ignored     Join Date: Oct 2009 Posts: 10,057 Originally Posted by Gingervytes Momentum is provided by pressure gradient force. Just like force is provided by gravity when you drop something. So momentum is conserved and no push on rocket. When you drop an object, it accelerates toward the earth and the earth accelerates (infinitesimally) toward it. Momentum is conserved in the object-earth system. When gas is pushed out of a rocket, it accelerates away from the rocket and the rocket accelerates away from the gas. Momentum is conserved in the gas-rocket system too.
 14th June 2019, 08:37 AM #3397 halleyscomet Penultimate Amazing     Join Date: Dec 2012 Posts: 10,244 Originally Posted by Jack by the hedge When you drop an object, it accelerates toward the earth and the earth accelerates (infinitesimally) toward it. Momentum is conserved in the object-earth system. When gas is pushed out of a rocket, it accelerates away from the rocket and the rocket accelerates away from the gas. Momentum is conserved in the gas-rocket system too. Keep in mind who you're responding to. __________________ Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!
 14th June 2019, 08:42 AM #3398 Elagabalus Philosopher   Join Date: Dec 2013 Posts: 5,511 Originally Posted by Gingervytes Where is your proof? A demonstration proving exactly what you are saying is required
14th June 2019, 08:55 AM   #3399
halleyscomet
Penultimate Amazing

Join Date: Dec 2012
Posts: 10,244
Originally Posted by Elagabalus
If you're seeking honest engagement and a sincere effort to debate the topic from Gingervytes then you're barking up the wrong tree.

Here, have a rocket video:
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__________________
Look what I found! There's this whole web site full of skeptics that spun off from the James Randy Education Foundation!

 14th June 2019, 09:07 AM #3400 JayUtah Penultimate Amazing     Join Date: Sep 2011 Posts: 18,378 Originally Posted by Jack by the hedge When you drop an object, it accelerates toward the earth and the earth accelerates (infinitesimally) toward it. Momentum is conserved in the object-earth system. True, but that's not his model of momentum. He considers only the momentum of the bowling ball, not the momentum of the earth-ball system. Momentum is created by gravity, which in his model is a wholly independent influence. Similarly in his model, he considers only the momentum of the exhaust gas, not the momentum of the gas-rocket system. Hence "pressure gradient force" -- another magical force in his physics -- in the form of ambient atmosphere pushes back against the escaping gas, preventing it from escaping fully, and causing a back pressure wave to be transmitted to the rocket. That's what he considers the Newtonian "reaction" to be.

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