How does knowing about physics set you apart from those around you?
We don’t fall for such ideas as ocean surfaces that can curve. Water
always seeks the lowest level possible. The top of a curve wouldn’t qualify.
Eman Puedama: "If everything else is drawn to the Earth- which it obviously is.. then why wouldn't water be as well? If you spill water, it falls downwards. Why shouldn't 'spilled water' go round a curve any less than dropped dirt could? The only good point I've seen a Flat Earther make is that sometimes, footage that appears to show the Earth's curvature is filmed with a fisheye lens and so can't be taken on trust- but that doesn't mean that a curve wouldn't otherwise be there - it just means that the curve you see can't be taken as evidence."
Me: "Put a magnifying glass lens or some similar small curved object and place it an a bowl and then pour water over the lens. What does the water do? There's just as much gravity pulling the water at the edges of the lens as there is in the middle."
LongLostWraith: "Have you ever owned a magnet? Gravity is similar to magnetism. If you accept that magnets exist, you must accept that gravity exists."
Me: "Except for one thing. Objects don't attract each other unless magnetism is involved. Do you see objects in the space station attracting each other? Why not? There is ZERO resistance."
LongLostWraith: "Actually, there's quite a bit of resistance inside the ISS. The gravitational forces between the various objects are so small that the air is enough to stop them from moving.
And yes, you're right about magnetism, that's why I said it's similar. Likewise, when gravity is involved (and anything with mass creates gravity) objects attract each other. But you normally can't see it in everyday life because gravity as a force is far weaker than electromagnetism."
LongLostWraith: "Oh, and I forgot to mention that the force between two objects (both with electromagnetism and with gravity) drops off by the square of the distance. Even if you bring two powerful magnets (of the order of 5 kilos of force) and separate them by 5 meters, they may take weeks to collide with one another. So, the idea that you'd expect normal, non-magnetic objects to visibly attract each other through gravity is absurd."
Me: "They are moving. You don't float in space.
"Why do astronauts aboard the International Space Station seem to float? They experience weightlessness not because of a lack of gravity but because the ISS, and they, are orbiting Earth in constant free fall
" -Smithsonianmag.com
Are you saying that if two objects exited the space station (where there is no air) they would immediately cling together (like asteroids do in the asteroid belt)?"
LongLostWraith: "Not immediately, it would take quite a bit of time, and ignoring the earth's influence (tidal forces), but yeah."
Quoting you: "the idea that you'd expect normal, non-magnetic objects to visibly attract each other through gravity is absurd"
Me: "You mean like your body to the earth."Does the moon cause one hair on your head to move?
LongLostWraith: "Not in any perceivable way, no. Note though that my hair's molecules are firmly held in place thanks to the electrostatic forces between them. I mean, the force is there, but it doesn't make any difference. The moon is pulling on my whole body with almost exactly the same force. The same doesn't apply to the earth's oceans though, as parts of it are much closer or farther than others."
Me: "There's a perceivable way with the ocean. How much weight is the moon gravity lifting?"
LongLostWraith: "The reason they're called "tidal forces" is because they're not "lifting" the water exactly. After all, you have two tides, one on the same side as the moon and another at the opposite side. It's complicated, I don't know the details either. You can search for "how do tides work" to learn more."
Me: "You're a wraith (ghost). I don't talk to the dead. The dead make shit up to fool the living."
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