So I just learned what Terminal Velocity is, that gravity pushes down as much as the air molecules are pushing up, meaning that it reaches as fast as it can when it reaches that point (terminal velocity) and will not go any faster.
With no air in space to stop the “pushing up” can things increasingly build up speed with not cap point?
I tried googling and it says this “The only terminal velocity in space is the speed of light. For anything moving more slowly than the speed of light the limiting factors are the specific impulse (the force applied multiplied by the time it acts) and the mass of the object, which together determine the acceleration and the time that acceleration acts.”
But I don’t really understand that, I don’t understand “specific impulse (the price applied multiplied by the time it acts)” what does “acts” mean?
Also I understand there is also no gravity in space, but I know that planets can exert gravity without actually pulling the object into its atmosphere…..
Can someone explain this to me in layman’s terms??
In: Physics
“Terminal velocity” implies some speed at which forces balance out. In falling, it’s the force of gravity speed you up vs. the friction of the air molecules slowing you down. Your speed of falling increases until these two forces balance out.
This may not be the question you’re asking, but maybe it is?
There is a similar concept for space travel. One of the realistic concepts for interstellar travel is called a “ram scoop” or “Bussard ram jet” . (There are a couple of realistic concepts, but this one is maybe the most realistic.)
Space isn’t empty. There’s atoms floating around – mostly hydrogen atoms. If you want to go fast, you have to account for the slowing force due to hitting those atoms. A ram-scoop cleverly would then use the atoms that it hits as fuel, like a turbocharger on a fast car (hey, you hit that atom and it already slowed you down, why not burn it in your fusion reactor, blow the exhaust out the back, and use it speed back up?)
The physics isn’t trivial. It depends on details like the elemental fractions of the gas in space. But it’s an interesting topic.
See “Bussard Ramjet” for details.
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