Why doesn’t it spin independently of me and I end up in another country or something? And if a spaceship watched earth from afar, at one point would it start spinning with earth and at what point can it observe the rotations of earth without being part of it?
In: Planetary Science
Because the helicopter is held up by the air and the air is moving along with the surface of the Earth.
A spaceship could conceivably stay “stationary” above the Earth as it rotates, but that would require constant thrust, and it would quickly run out of fuel. Real spaceships stay up by [orbiting around the Earth.](https://what-if.xkcd.com/58/)
>Why doesn’t it spin independently of me and I end up in another country or something?
Because you took off from a helicopter that was sitting on the ground. It already was moving with the ground, and it doesn’t lose that speed just because it takes off. It’s the same reason a ball doesn’t just shoot off at hundreds of miles per hour when you toss it up.
>And if a spaceship watched earth from afar, at one point would it start spinning with earth and at what point can it observe the rotations of earth without being part of it?
If it’s a spaceship…it can do either (assuming it has enough fuel). It just depends on what the crew wants to do. There are geosynchronous orbits, where the spaceship will stay above the same spot on the Earth indefinitely, but you can also spin in the opposite direction, or whatever way you want. An alien spaceship from far away wouldn’t be dragged along with Earth’s rotation. The crew would just pick how they want to move.
Yes; (assuming you can stay in one spot and not drift or be pushed by any force) but you would need to wait a long time
Vantage points matter a lot; watching the earth rotate underneath you from 1000ft will look/feel different from watching earth rotate from 50 miles up
Your helicopter is in the air, which moves almost as fast as the earth. That wind you feel from time to time is actually the air moving at a different speed from the earth. In a true hover, the helicopter would actually move over the earth below it, but not at the speed of the earth’s spin, but along with the air moving.
Go to the western side of the room you’re in. Jump as high as you can.
The reason the wall didn’t come through and hit you while you were in the air is the same reason the helicopter keeps spinning with the Earth even though it is in the air.
You are spinning with the earth. You’re spinning with the earth right now. When you jump up or fly up, you don’t suddenly lose that angular momentum and the centripetal force that flings you around in a circle.
Yes, you and everything else on the earth are being flung around in a circle by gravity and your existing angular momentum which has an inertia tend to want to be conserved. You don’t feel like you’re rotating or being flung around, but that’s because you are observing from a co-rotating reference frame, so to you, you, the ground under you, and indeed the entire earth is not rotating but still.
If you were an astronaut in space observing from a comoving inertial (non co-rotating) reference frame, you would see the earth and every patch of ground and air on it spinning around its axis.
[removed]
1) You are moving with the air mass which is moving with the rotation of the earth.
2) By definition, hovering in a helicopter is very deliberately maneuvering the helicopter in reference to things on the ground to stay in one place in reference to them. The wind is pushing the helicopter which has to be counteracted to stay stationary. The earth is very slowly and imperceptibly moving, but the pilot is looking out his front, left and right window to keep everything stable and the same. Its less like hovering as you think of it and more like flying in formation with the ground. If the earth was moving so fast that you could see it shifting, a hovering aircraft would still appear stationary as they are very intentionally flying in a way to stay over the same piece of dirt.
If you jump up in a train, you aren’t thrown back into the rear of the train. You keep moving with the train. And if you didn’t know it was a train, you would not know you were moving.
Same with earth, it’s the “train”, and you are moving with it. So is a helicopter, even while “jumping”, or flying.
That being said, the air DOES tend to not move quite as fast as the ground below it (it “slips”), and that generates winds and weather patterns. That’s why winds on a global scale have a very definite pattern. Go to windy.com and zoom out the globe and you’ll see this pattern.
The helicopter and air were spinning with the earth before liftoff and continue to after liftoff.
Just like the helicopter and air were moving with the earth around the sun and don’t immediately “stay behind” when they “float” in the air.
The helicopter flying is not absolutely hovering free from all influences. It started its movement frame connected to the earth and lifting off doesn’t decouple it from that.
Latest Answers