> Passengers will not experience weightlessness
If this needs to be said, i think its not clear to everyone... being "in space" is not what causes weightlessness. "Falling" towards your local gravitational source does it. This includes orbiting.
If this needs to be said, i think its not clear to everyone... being "in space" is not what causes weightlessness. "Falling" towards your local gravitational source does it. This includes orbiting.
Until they start decelerating, which is immediately. They’ll also feel it fairly rapidly, I think.
https://en.wikipedia.org/wiki/Reduced-gravity_aircraft#Opera... (emphasis added):
“The sensation of weightlessness is achieved by reducing thrust and lowering the nose to maintain a neutral, or "zero lift", configuration such that the aircraft follows a ballistic trajectory, with engine thrust exactly compensating for drag”
If you crush something in a hydraulic press, it might have balanced forces and zero acceleration.
For that matter, Im not accelerating when I lay on the surface of the earth, but I hardly feel weightless.
https://en.wikipedia.org/wiki/Drop_tube -- https://en.wikipedia.org/wiki/Reduced-gravity_aircraft -- https://en.wikipedia.org/wiki/Free_fall
Our brain is used to gravity. That is why weightlessness feels weird.
But falling and weightlessness are indistinguishable to your brain. They are exactly the same thing.
So, if all the gravity around you suddenly disappeared, your brain would initially tell you that you are falling.
Only after some time would you convince yourself that, "No, I'm not falling... Gravity just disappeared. I'm just weightless."
The opposite of falling is accelerating, and you feel acceleration. A rocket rocketing in an empty universe would feel the same as a rocket rocketing in orbit would feel the same as a rocket just sitting around on Earth. Wait, that last one's different...
We happen to live most of lives in a somewhat exceptional case of constant acceleration (with respect to falling). The ground below our feet has gotten us pretty used to acceleration. But, if you jump, you'll feel like falling too!
Weightlessness only feels weird because we rarely feel it.
If you were suddenly in empty space (e.g. in an area with zero intrinsic acceleration), you would feel like you are falling.
Because the feeling of falling is actually the feeling of NOT having the constant gravity (i.e. acceleration) you're used to.
If you were born in weightlessness, gravity would be the strange feeling (cue Bane saying, "you only adopted weightlessness, I was born in it").
Considering the same question for geostationary orbits had me confused for a moment and then I realised we are not in a fixed location relative to the Earth, thanks to the Earth's spin. I wonder what extra percentage weight we would feel if it weren't spinning.
The centripetal force question is a little more challenging, but still in the realm of algebra. The complicated part is setting up the problem and understanding where the forces are coming from and if/how they cancel each other.
https://www.quora.com/What-is-the-acceleration-due-to-gravit...
At the ISS, the extra distance from the center of the earth is minimal compared to the radius of the earth itself. Therefore, there wouldn't be a great difference.
You have to get pretty far away to experience true "weightlessness".
So the answer is, if you could hold the ISS stationary without falling, people in it would feel almost as much gravity. You would have to go much higher than the ISS to feel weightless without orbiting/falling.
Assuming people feel weightless at 1m/s2 or less, you can solve for that! And the answer is 13,600 km.
As for the centrifugal force from the Earth's rotation, Wikipedia puts it at about 0.3% (which, added to the effect of the Earth's bulge, means you feel a total of 0.5% less weight at the equator than at the poles).
The convention was to never use the term "zero gravity," since using that term would perpetuate a common misunderstanding. Instead, we've used the term "microgravity" in its place—which makes sense, as there are still small gravitational forces acting on every object in space.
NASA also published a webpage with a good explanation of what microgravity is, with a nice diagram of how it works (including a visual of the parabolic flight): https://www.nasa.gov/learning-resources/for-kids-and-student...
Indoor skydiving lets you ‘fall’ for hours, but you don’t accelerate so you don’t feel weightless.