this post was submitted on 03 Aug 2024
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How can a rocket and thrusters work in space when there is no atmosphere to push against? The space ship/rocket would stay still and all the thrust matter would just be ejected. - For example, If the rocket wants to turn left, it is always shown as firing a thruster from the right side that turns the rocket/ship to the left. But in a vacuum all that would happen is the matter that came out of the thruster would be sucked into the vacuum and spread out evenly. The ship would not move. 🤔 Nothing to push against.
Edit: I see now (from the more helpful replies) That it is not the rocket pushing back, but rather the combusting expanding fuel that is pushing the rocket forward. Which makes sense to me now.
Google says thrusters are similar, in that it is expanding steam etc.
I think you missed a /s
Given how many people think that railguns have no recoil because "there is no explosion" they might actually seriously believe what they just wrote.
Scientific illiteracy is through the roof.
Or maybe it's the same as it it's always been it's just that people that are scientifically illiterate are given platforms to speak their illiteracy as truth.
I remember when Falkon 9 was doing its first landings, the whole YouTube comments section was filled with flat earthers claiming it's a CGI. Now you can take a car and go watch landings in person, I wonder where all those people went.
Are you saying that I am scientifically illiterate? For asking a question about how a rocket that uses thrust could work in an environment with nothing to thrust against? I don't think it's a dumb question. Sure there may be an answer that I am yet to learn, but that is why I am asking the question and seeing what answers I get. Maybe you were born with all the knowledge of the human race, but the rest of us have to learn it. And some of it is true, and some of it is BS.
Am I saying you are scientifically illiterate?
Based on the previous statements, yes. However, as a matter of fact, not necessarily insult.
The good news is you're following up with questions and want to learn more, instead of doubling down. With curiosity you will become more literate.
The education system in the country you are from has failed you. Assuming you are in your mid-late teens, or older, scientific topics should have already been taught in what North America would call "middle school" (11-14 years old). That teaches you things like conservation of momentum.
There is a reason why it's called illiteracy, because there is an expectation that the baseline level of education everyone in developed countries receives teaches them the fundamentals of how the world around them works. Without this fundamental understanding it's not possible to understand more complex topics that build upon it, stunting growth.
I agree with you. Good comment. I am an interesting case, I was born in the west, and I'm back home now, but my parents traveled during my school years, and my education has holes. (One of which being how rockets work apparently! lol)
To answer your last comment, i think it must be the internet that makes the literate annoyed with the less literate, and the illiterate frustrated with the perceived arrogance of the literate. Back in time I would imagine that both parties would mix in separate circles and not share in conversations like this.
Thanks for your comments
You are scientifically illiterate if you are asking questions that have easily discoverable answers (as in this example, centuries of confirmed results)
The burn from the thrusters doesn't push against space, it pushes against the rocket.
For more easily discoverable answers to basic physics questions, perhaps take a physics 101 course. Or just Google your question.
Or do it the way you just did it... Cunningham's law and all that. But be aware that people will consider you scientifically illiterate if you do it the way you just did it.
Idk what you mean thrust against, but there's always equal and opposite forces. Say you were floating in space and were holding a hammer. You throw the hammer away from you. You will also move away from the hammer as it moves away from you (albeit at different speeds relative to each object's mass). The conservation of momentum.
https://youtu.be/Fp7D5D8Bqjc?si=KyIr0doj2Pinf6U5
Here's an Eli5 video on how rockets work.
https://youtu.be/jI-HeXhsUIg?si=UvtAkVdbPDYimitY
Chemical/liquid rockets and compressed gas thrusters are two different things with different functions. You’re right that lighting a fire in space won’t do much but make a cool firework. A thruster doesn’t so much push against space as it does nudge the ship in the other direction. Newton’s 3rd law and all that except the second “body” in this case isn’t something physical outside the ship but rather the force of the the gas leaving the thruster nozzle causing a recoil.
Aren't Railguns works of fiction?
https://youtu.be/O2QqOvFMG_A
Really thought these things were a work of fiction. I guess it's because in the movies they pretend it's a laser instead of a high velocity missile of some kind.