r/stupidpeoplefacebook • • 9h ago

Source :Trust Me Bro

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u/WritersChopBlock 5h ago edited 4h ago

CONSIDER THE SCIENCE BEHIND THIS.

If you have taken physics or you are science-oriented, you'll realize that this is very likely a sham. I'm not 100% certain, but if you think about the physics, what is being suggested is impossible.

Think about the enormous amount of energy required to keep this car afloat if it's based on propellant. Consider how Harrier Jump jets spend so much fuel to do something similar for a few seconds.

The only way to accomplish this practically would be to rely on a technology that counteracts gravitational forces without expending energy. The aliens that have been spotted sporadically likely use such a technology. But we are nowhere near that level of technology yet. [Edit - deleted: Our scientists still don't know where gravity comes from.]

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u/Vast-Difficulty1542 4h ago

Yes. We can see why this is a sham using Tsiolkovsky's formula.

∆v = ln(m0/m1)•Isp•9,8. For every second of hovering, the car expends 9,8 m/s of ∆v. This means that a single hour of flight will cost you around 36000 m/s ∆v. To put this into perspective, the orbital speed of the ISS is 7,66 km/s, or 7660 m/s. This means that, with this amount of ∆v, if our car ended up in LEO height, it would take less fuel to orbit Earth. And now look at the size of rockets we have to deliver stuff into LEO. Obviously, it's a very gross oversimplification, but it can give you a sense of how unrealistic flying cars would actually be. Unless we use an engine with ridiculously high Isp (similar to one of an Ion engine), and it somehow has enough thrust to lift the car off the ground (which ion engines don't, and they also don't even work in the atmosphere), this remains extremely impractical. What would be more practical, is if we used lift to make the car fly, which actually has already been done.

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u/Tsukee 2h ago

This, if you can hover using non oxygen breathing engines for more than like 20minutes, and if you can increase thrust to double (2x thrust to weight) for half the time (10min) your 'car' could very likely get into orbit with that much time and thrust