eli5: As earth rotates, why are we not able to travel to different places just by hovering above the ground? lol
In: Physics
The earth’s rotation is already moving you in the direction of rotation so when you’re hovering, you’re not standing still. You can think of it as you are moving diagonally forward with the earth as you’re hovering. Now it’s faster to travel to a location against the rotation of earth than to travel with the rotation the same amount of distance. That’s probably what you’re thinking of.
Depending on where you are on the planet, the ground under your feet is moving at anything up to 1000mph.
What this means, of course, is that everything that’s on that bit of ground – including the building you’re in, and you yourself, are also moving at that speed. The air around you is also being dragged with the ground underneath it, so the atmosphere is spinning around at the same sort of speed – if it wasn’t dragged with the earth below it, you’d find yourself in a permanent 1000mph wind.
If I’m looking down at the earth from space, I’ll observe that, relative to me, the atmosphere is moving. For someone standing on the surface of the earth the atmosphere is still (still-ish – if we ignore wind)
What this means, then, is that when we say ‘hover’ we’re staying above the same bit of ground, but also in more-or-less the same bit of air. Moving away from our original bit of air/ground means that we need to actually move rather than just hovering in place.
Newton’s first law of motion on a very large scale.
An object in motion will remain in motion unless acted upon by another force.
Think of it like a car moving, and when you’re inside of it and you pick up an object and drop it to your lap; it will fall to your lap as it would if you were sitting let’s say, in your living room. This happens because if the car is driving at 50mph, your object that you dropped has also been accelerated to that speed, and now the car, yourself and the object are traveling at 50mph. If you add an external force, like if you were to do that same experiment by opening the window and dropping it outside the car, now you have the air friction that will slow the object down and make it stay behind as you drop it. Inside the car, the air friction is blocked by the windows and glass.
Us humans and everything on earth are the objects, and the earth is our car. Our shield protecting us from exterior forces is our atmosphere.
Sorry can’t explain properly but this 2 min video should answer your question.
You are also moving as fast as the earth is, cause yknow, you are on earth. So if you jump you just move with earth. If you wanted to be still relative to the earth’s rotation you would simply be flying from our perspective.
The air around us moves with the rotation of the earth, and thus if we just hover, the air pulls is with it
Have you ever had a bug fly around your car? It’s not harder for the bug to fly towards the driver even if the car is going fast. That’s because the car is bringing the air inside the car with it. The fly only has to “swim” through that air at a relative rate.
The same goes for the planet’s air. The air we live in is being brought around at the same speed as the planet itself, and we are being kept relatively inert within that space, so it matters not how fast the planet is continuously going (as long as it stays continuous).
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