This makes sense but it can't be demonstrated. In your example, the water in the spun bucket would be level with the base of the bucket. Would be great if you could devise a gravity machine and stick it in the center of a ball and then pour some water on it!
The particle nature of water and the effects of forces on particles and the statistical mechanics that large ensembles of particles obey can in fact be demonstrated. In my example, I believe it would actually be slightly convex. Plus off-center since it's getting pushed along by the bucket. As far as a gravity machine, the bucket thing is a way to get a (near) central force like gravity in the water's reference frame, just with an outwards instead of inwards direction.
The object would be hidden because of the limitations of human sight and perspective. There is plenty of amateur footage of ships hidden by 'earths curvature', yet are brought into view with a powerful enough zoom lens.
This just restates what I said. If zooming in makes it re-appear, than it is close enough to not be hidden behind the curve, and the zoom just overcame one of the other reasons things disappear.
Take a look here. Refraction effects also play a role in observable distance.
https://www.metabunk.org/curve/https://www.metabunk.org/curve/
VBF was asking about the curve of the earth, not why we can sometimes see things would be hidden. I'm aware that refraction plays a role in visibility, and have brought that up earlier in this thread.
Yet if you shoot a cannonball straight up it will land within a few feet of where it was launched.
Double-checked, I goofed and worked things out for a spinning disk like the wikipedia gif. On a sphere, going straight up involves some change of radius relative to the axis of rotation unless you're on a pole over the course of your air-time. On a spinning disk, if you jump straight up then your radius from the rotation axis doesn't change. So on a sphere I'd expect there to be some change in landing position,
@VonBonfire.
You will say the Coriolis effect is negligible at this scale
I'd have to do the calculations before saying that. Would have to review first. It's been a bit since I did classical mechanics, as is evident from the earlier goof. At the scale of VBF hopping up and down in his driveway though, over the timescale he'd do it before getting bored and going to play his twins, and given tolerance of a human jump, I'd expect it to be negligible.
but that is basically the same answer for everything about globe earth -- everything becomes apparent at scales too vast to directly demonstrate (Except for the nonsense about the direction of toilets flushing I guess).
We've been down this road before in this thread, and I was unsatisfied with the way you handled the discussion. It is a big part of the reason why I think you're probably not arguing in good faith. Because of that, I don't think it's worth my time to engage with you beyond this point. I may occasionally as I feel like it, but don't expect it. I'm primarily focusing on engaging with VBF for now, since at least in my direct interactions with him there still seems to be the possibility of a good-faith discussion. Thanks for catching the Coriolis goof though.