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
Escape velocity only applies to unpowered objects. Just as you say, a rocket could just keep going at low speeds and eventually overcome the pull of the Earth, as long as it had enough fuel to keep burning that long. But that fuel requirement is a very big *if*: fuel adds weight, which makes the rocket harder to launch.
Escape velocity is the way around this problem. Once a rocket hits escape velocity, it doesn’t need fuel to keep going, so it doesn’t need to carry any more fuel than needed to reach escape velocity in the first place (and maybe a little more for maneuvering). This allows the rocket to be lighter, which makes it easier to launch.
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