I can’t wrap my mind around why you need to be going a certain speed to escape the pull from earth’s gravity.
In my mind I envision 5 people playing tug of war with a bull. The people are exerting a pulling force but the bull would be able to overcome it. Let’s say the humans never get tired but the bull will be able to exceed the forces pulling it back and continue to move forward. That can happen at 22mph or 2mph.
Outside of it being severely inefficient (I’m guessing), why can’t an object just travel upwards at low speeds and eventually overcome the pull of the earth because it has lots of… torque (for lack of a better word)?
In: Physics
Gravity will always slow you down, even at very large distances (though it will be much weaker then).
If you start with a certain velocity from the surface of earth (and cannot accelerate further), you will get slower and slower over time. If your initial velocity was too low then you will stop at some point and change directions, and then fall back towards earth.
Only if you have the escape velocity or higher, you have enough energy to overcome (escape) the gravity completely and you will never be stopped by the earth gravity.
However that is only important if you have something that starts with a constant velocity at earth and can not accelerate by itself. If you have something like a rocket, which can accelerate by itself, then escape velocity you don’t necessarily need escape velocity initially (however building a rocket that can accelerate in space for long times is also not easy).
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