I heard something new that realy makes you wander. If the earth is rotating as they say than how airplanes can go in straight line? If earth is moving under them they should land way off the desired destinacion.. 😮 They are not connected to the earth so rotacion shouldnt apply to them, it applyes only to cars and runing animals but not on airplains and bierds.. Also when you jump from baloon that is wery high up, you shouldnt fall straight down, if the earth is rotating it should move under you and you could newer fall on the same spot that you jumped over.. 🫢

I cant beleave this newer came to my mind for entire life.. 😵

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[–] [email protected] 19 points 3 days ago* (last edited 3 days ago) (4 children)

In the event you're actually asking for an explanation, since that is what this community is for:

You are correct. The Earth rotates underneath airplanes or anything else in the air. Airplane pilots navigate to airports, they don't just land where the airport was 2 hours ago. This is accounted for in flight schedules. Skydivers are only falling for about 5 minutes so the rotation underneath them is negligible. Birds, similar to pilots, just keep going until they're where they want to be.

Also, the Earth is a spheroid.

[–] [email protected] 9 points 3 days ago* (last edited 3 days ago)

Skydivers are only falling for about 5 minutes so the rotation underneath them is negligible.

Plus, like planes, they're flying - so aiming for a target (while their lift is far less than aircraft, they do have some, and can orient and direct themselves).

They're also in the atmosphere, which is rotating with the earth (part of why there are winds).

[–] [email protected] 4 points 3 days ago (2 children)

That's just plain wrong.

Everything on earth moves with the earth's rotation because of inertia or more precisely because of conservation of angular momentum.

OP: Any object that is moving keeps moving in that direction unless some force changes that. So every plane keeps moving with the earth's rotation because it started that way. Whatever speed it picks up from its engines is in addition to that.

[–] [email protected] 3 points 2 days ago

Tnx that makes sense

[–] [email protected] 2 points 2 days ago (1 children)

You're right, but my point was the Earth is not flat.

[–] [email protected] 3 points 2 days ago (1 children)

Sure, but the earth does not rotate underneath airplanes. Airplanes rotate with the earth.

[–] [email protected] 1 points 2 days ago

That's why I said "you're right." No need to be a jerk

[–] [email protected] 1 points 3 days ago (2 children)

I just did guick math and it turns out in 5minutrs it should move 135km if you jump on equator.

[–] Nurse_Robot 6 points 3 days ago (1 children)

Replying to your most recent comment. You've had a lot of explanations provided, in multiple easy to digest packages. You haven't replied to any of the answers that people spent a decent amount of time to provide you. Do you understand now and don't feel inclined to acknowledge anyone who helped you get there? Do you reject their explanations without feeling the need to respond? What's up bro

[–] [email protected] 2 points 2 days ago

Easy dude i was thinking about the first reply and thats why i didnt read other replyes..

[–] [email protected] 4 points 3 days ago

You're moving that fast too, you don't suddenly stop rotating with the Earth when you jump.

[–] [email protected] 0 points 3 days ago (1 children)

Wait a second, if earth is taking 24h to rotate full circle it means it moves a lot in 5 minuts its not negligible. We can do math how much it should move in meters. So lets do that.

[–] [email protected] 5 points 3 days ago

The thing you're jumping from is moving. The air masses are moving. The earth is moving. The falling object is moving. There are several factors at play here. If you were still relative to the earth at the moment you jumped from, say a hot air balloon and the fall took you 5 minutes and you were just falling straight down then you'd miss the target by around 150 kilometers.

[–] [email protected] 19 points 3 days ago (2 children)

I can't tell if this is a joke or they're really this stupid.

[–] [email protected] 2 points 2 days ago

No need to be rude i didnt call you stupid because you dont know many elementary stuff..

[–] [email protected] 6 points 3 days ago

"Ignorant" is a more generous term. They clearly haven't had a even a basic earth sciences or physics class.

[–] tomi000 2 points 2 days ago

People chill, its obviously satire

[–] Nurse_Robot 10 points 3 days ago

Inertia do be crazy

[–] Carrolade 7 points 3 days ago (1 children)

If you're in a moving car, and you toss something small straight up into the air, does it come straight back down to your hand, or way behind it?

[–] r0ertel 1 points 3 days ago

This is a good start to explain it. Many of the posts here are also neglecting that the air around the earth is also moving along with the earth, but often at a different speed. It is not fixed in space.

For example, if you've ever paddled a canoe across a flowing river, you'll either end up not across from the point you left from or you've steered the canoe as if you were intending to land upstream. This is because the water is pushing the canoe downstream.

Also, the comments (as if the time of this post) are all neglecting the point of reference.

An analogy on point of reference would be if you're on a train, sitting at a table facing the rear of the train and the train is moving in the forward direction at a constant speed on a plain, if you drop an orange on the floor of the train, will it immediately roll to the back of the train?

In airplanes there is often a big difference between land speed and air speed. That is (one of the reasons) why the return trip is not the same duration when you travel in the east-west (or west-east) direction. The airplane is pushing against the airaround it whereas a car is pushing against the ground (Earth).

[–] [email protected] 4 points 3 days ago (1 children)

wonder*

[–] [email protected] 4 points 3 days ago* (last edited 3 days ago)

Nah, I stepped away for a bit, it made me wander.

(Imagine frogs and crickets jumping at 1000mph)

[–] [email protected] 3 points 3 days ago (2 children)

Think of it this way: imagine a slowly moving stream. Anything in the stream will move along with the current and from its perspective will be “stationary” in the current, right?

But then think about the surface of the stream: the air above it isn’t moving, so the stream surface is rubbing along the air interface, creating drag. This means that the air is going to end up moving a little bit in the direction of the stream, and the stream surface is going to be moving a bit slower than the main body of water.

Wrap that in a circle, and that’s what the layers of the earth’s atmosphere are like. So a skydiver is “diving” in an atmosphere that is relatively (but not completely) stationary above a certain spot on the earth.

For an experiment you can try yourself, fill a bucket with water, and then spin around in a circle holding the bucket. All the water stays in the bucket instead of sloshing out one side due to the bucket moving through space. This is a combination of inertia and force acting on the contents of the bucket.

The earth is big enough to have a gravitational force strong enough to resist shear) the rubbing at the interface), and there’s nothing really out there in space for it to rub against. So the air is more impacted by the gravity of the moon and the heat of the sun than it is by friction against space or inertia overcoming gravity to send things flying off the earth at an angle.

[–] [email protected] 0 points 2 days ago (1 children)

Ok so when you talk abou inersia, does that mean that if you drive airplain in the same direction as earth rotacion you will gain more speed and inertia will get stronger than gravity and you will slowly start to levitate? And if that is trye than going in oposite direction will make you go slower than just standing on the ground and gravity should have bigger efect on you and start pushing you to the flor of airplain?

[–] [email protected] 1 points 1 day ago (1 children)

Let me ask you the same thing about swimming in moving water… relative to the water, do you slowly start to levitate?

No; if the referent is the water, to you it is stationary and the ground is moving past it; other than the slight movements at the interfaces, you’ll have the same interaction with the water no matter which way you move.

Likewise, the earth is both spinning AND rotating around the sun with an axial tilt. So if you fly in the direction of the earth’s rotation, you’ll be going faster relative to some fixed point in space, but relative to the earth’s surface, there isn’t a noticeable difference in forces going one way or the other. If there were, you’d already have flown off the surface just by standing up. Refer back to my bucket example for how that works.

[–] [email protected] 1 points 14 hours ago

Ok so since inertia happends when object change its state, it is when we change our speed or when we change our trajectory.

For example when i sit in car and it quckly accelerates i feel inertia, or when it run 100km/h for 5min i dont feel anything but if it accelerates quickly to 150km/h i feel inertia again. Or if he starts turning while keeping its speed to 100km/h i will feel inertia if that turn is curved enough, if its to soft i may not feel it.

On earth while just standing we dont change our speed, its constant so there is no inertia because of that. But we change our trajectory constantly because we dont go straight, we are constantly turning since its rotating. So inertia should apply to us right? But gravity is stronger and thats why we dont fly of the ground?

[–] Nurse_Robot 1 points 3 days ago

That's a wonderful ELI5 explanation! I absolutely love it. If I had to critique it, I would challenge you to explain the jet streams at >30,000 ft. Stupid fluid dynamics making air move weird. You did a great job presenting the facts in a relatable way that I think most people can grasp and understand

[–] Lasherz12 3 points 3 days ago* (last edited 3 days ago) (1 children)

When you hop inside of a moving truck while it's on the road going 60mph do you expect to crash through the back? The air is also moving, unless you think there are routinely storms with winds of ~1000 mph winds?

[–] [email protected] 1 points 2 days ago

Yea that makes sense

[–] Boinkage 3 points 3 days ago (1 children)

bierds

[–] [email protected] -1 points 3 days ago

Sory eanglish is not my main language 😅😂