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
ELI5 really : you look at a fish in a fish tank on the ground. The fish tank moves with the ground and you expect the fish to move with the fish tank right? You don’t think the window will slam the fish in the face as the tank move with the earth spin but the fish would be still and move through water.
Well, your helicopter is the fish and it is the exact same story because air is exactly like water. Sure it is less dense and we can’t see it. But your fish in water and your helicopter in the air will move with the fluid around them similarly. Think of an helicopter as floating mid air.
If the air around you was objectively stationary relative to the moving Earth underneath it, you’d be in 900+ MPH winds all the time. So obviously the air is also moving along with the Earth. When you are up in the air, you are then are also moving, so say stay roughly over the same spot.
The earth is spinning and the helicopter is “Along for the ride”, moving with the earth. When it lifts off that momentum stays with it. It’s already up to speed and going the same direction as the earth.
It’s similar to when you throw a ball. The ball leaves your hand but continues at a speed similar to what your hand was traveling before you let go. That’s how throwing works.
Because the atmosphere rotates with the earth. If it didn’t, we’d constantly be running into stationary air at 1000 miles per hour.
If you go vertical and turn right you have a head start in speed instantly at 1000mph if you turn left it’s a lot of head wind
When helicopter is on the ground it’s moving with the Earth, so is the air that is all around you otherwise there would be such strong winds that would blow everything away (if the whole atmosphere wasn’t moving with the Earth).
So when you fly up with the helicopter you are just moving in air that is already moving with the Earth.
Same goes for rocket ships. When they launch, at the moment of lift off they are still moving with the Earth and the atmosphere. Then depending on their direction (once they lift off and tilt a little) they start either increasing or decreasing their speed relative to the Earth rotation.
Once rocket is in space it’s still being affected by the Earths spin, only by flying in the opposite direction of the Earth spin they can eventually become so fast that it looks like it’s doing one rotation around the Earth in 24 hours. That is when it’s speed relative to the Earth’s spin would be 0.
ISS (international space station) witnesses 16 sunrises and sunsets in 24h period because they orbit the Earth every 90 minutes. That is how fast the ISS has to move to stay in relatively stable orbit as to not fall down into Earth’s atmosphere or fly off into space.
Once you start to observe things in relations one to another whole new world opens up to you and you start to learn a lot of new thing and the amazement never stops.
Because you , the helicopter, and all the air around you are all already moving with the rotation of the earth. When you lift off, you are still moving with the earth due to inertia and gravity, but also now moving up at the same time
It actually does, that’s called the correolis effect, and it effects every flying object. Snipers & artillerymen actually have to do the math for that on their shots or they’ll miss.
But, when you took off, you (and the air around you) were already moving in the same speed & direction as the ground, so momentum is still carrying you in that direction at that speed. The earth does move under you, but it is not moving very fast relative to your initial velocity, so you normally wouldn’t notice it unless you’re at a really high altitude or you’re taking very precise measurements.
If you are hovering, that means you’re maintaining a position in the air relative to a fixed position on the earth. If the earth is moving beneath you, you are not hovering.
When you’re inside a train, the air around you doesn’t feel like it’s moving. If you’re inside the train and you jump, the train doesn’t leave you behind and you keep all the same momentum you had standing still inside the train. You can only tell how fast you are going by sticking your hand outside the train. This is what it’s like being inside the Earth’s atmosphere. The air is moving along with us.
Air resistance is relative. If you are moving at the same speed as all the air around you and in the same direction, it feels like standing still. The less similar your speed and direction, the more the air resists, the harder you need to push the air out of your way. Things mostly slow down from collision or propulsion. Gravity makes you collide with the ground, rockets use propulsion to land safely, in the case of air resistance you are colliding with countless air particles.
But when you fly your helicopter straight up and hover, you haven’t done anything for the air to resist because it is moving exactly the same as you horizontally. Everything around you is moving at the same speed as you.
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