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
You don’t. Escape velocity only applies to ballistic launches, where the object you’re launching has no propulsion of its own and has to get all of its speed *at launch*. Shoot a cannon ball out of a cannon, and you know that when the ball leaves the cannon it has to be traveling faster than Earth’s escape velocity, or it will come crashing back to Earth.
Launch a rocket, however, and the concept of escape velocity becomes moot. As you said, you can, in principle, fly up at an absolute snail’s pace, and as long as you keep flying up, you will eventually make it to space. It’s just (again, as you said), rather inefficient to do it that way, because every second you spend in Earth’s gravity is a second that this gravity saps away your speed.
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