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Alternative_Bar_6441 OP t1_jefr3v0 wrote

So if i stay on the same spot afloat for 12 hours would i technically be in another far away place


Bonneville865 t1_jefrwt9 wrote

Not really, for the same reason that if you throw a baseball into the air inside a car, the baseball doesn’t land behind you, in the spot where it left your hand.

You, like the baseball, have forward momentum in the direction the earth is moving. You aren’t actually jumping straight up; you’re jumping forward at about 1,000 miles per hour. It just feels like straight up because everything else is also moving at the speed of the earth’s rotation.


Alternative_Bar_6441 OP t1_jefsdf1 wrote

So everything we have been taught about jumping is a lie,is it just forward momentum?


PM_ur_Rump t1_jeft0tg wrote

No. You are jumping up, but also moving sideways at a speed basically equal relative to the Earth's rotation.

You are already moving at that speed, as is everything around you, including the air (assuming no wind), so from your perspective, all the motion is up/down.


WarmMoistLeather t1_jeftszw wrote

What do you mean by "same spot"? Relative to what? The sun? The galactic center?

I'm going to assume you mean the standard "what would happen if I hovered in a helicopter for hours, would I be somewhere else?"

No. You are moving right now. When a helicopter (or you) hovers, it is matching the rotational speed of the ground below it. Let's say what you mean is that you take off at sunrise and for 12 hours you want to keep the sun at the same visual spot on the horizon. You would no longer be hovering because you would have to counter your current speed, meaning you would have to race West at something like 1000 miles an hour. You have to counter the rotational speed of the earth at your latitude and I believe if you do this at sunrise, you don't have to add the Earth's speed around the sun, you just have to maintain your elevation because the earth is moving toward you as it sounds beneath you.


notmyting t1_jefrjap wrote

That is also true yes, the earth is moving around the sun at an average speed of 29.78 km/s. And the sun is moving around the galactic centre at roughly 220 km/s. So you will move relatively far over 12 hours.


DestinTheLion t1_jeh0ohd wrote

If you are moving fowards and jumping, what would slow you down? Air resistance. But in the case of you jumping with the earth, the air is moving forwards with you overall. So you keep moving at the same speed as the earth.