Why is there an escape velocity?

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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

12 Answers

Anonymous 0 Comments

Escape velocity does not mean “you have to be going this fast to escape the Earth”. Escape velocity means “if you’re going this fast, you would escape Earth even if you turned your engines off”, i.e. it describes the minimum speed needed for an **unpowered** object to escape.

If you have an engine, you can definitely just creep away from the Earth slowly. It will just require more energy/fuel than necessary due to taking longer because you’re moving slower.

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